Soft drink and fruit juice problems solved Philip R. Ashurst and Robert Hargitt
Published by Woodhead Publishing Limited, Abington Hall, Granta Park, Great Abington, Cambridge CB21 6AH, UK www.woodheadpublishing.com Woodhead Publishing India Private Limited, G-2, Vardaan House, 7/28 Ansari Road, Daryaganj, New Delhi ± 110002, India Published in North America by CRC Press LLC, 6000 Broken Sound Parkway, NW, Suite 300, Boca Raton, FL 33487, USA First published 2009, Woodhead Publishing Limited and CRC Press LLC ß 2009, Woodhead Publishing Limited The authors have asserted their moral rights. This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. Reasonable efforts have been made to publish reliable data and information, but the authors and the publishers cannot assume responsibility for the validity of all materials. Neither the authors nor the publishers, nor anyone else associated with this publication, shall be liable for any loss, damage or liability directly or indirectly caused or alleged to be caused by this book. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming and recording, or by any information storage or retrieval system, without permission in writing from Woodhead Publishing Limited. The consent of Woodhead Publishing Limited does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from Woodhead Publishing Limited for such copying. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. Library of Congress Cataloging in Publication Data A catalog record for this book is available from the Library of Congress. Woodhead Publishing Limited ISBN 978-1-84569-326-8 (book) Woodhead Publishing Limited ISBN 978-1-84569-706-8 (e-book) CRC Press ISBN 978-1-4200-7437-6 CRC Press order number: WP7437 The publishers' policy is to use permanent paper from mills that operate a sustainable forestry policy, and which has been manufactured from pulp which is processed using acid-free and elemental chlorine-free practices. Furthermore, the publishers ensure that the text paper and cover board used have met acceptable environmental accreditation standards. Typeset by Godiva Publishing Services Limited, Coventry, West Midlands, UK Printed by TJ International Limited, Padstow, Cornwall, UK
Preface
Many previous publications on the topics of soft drinks and fruit juices have been written in a style that addresses background issues of the subject. This book, Soft drink and fruit juice problems solved, is an intensely practical work that is intended to appear on the shelf of every beverage technologist, whether they work in a large multinational company or in a small- or medium-sized business that is producing for a niche market. The authors both have wide experience of the beverage industry and, at the outset, they attempted to cover a wide range of areas of the industry business and to come up with what they believed were the principal problems associated with those areas. The object of this work is to pass on that collected experience. The book has been assembled in a chapter style that covers a wide spectrum. Starting with product development, the book then moves on to potential problems with beverage ingredients and then to consider manufacturing problems and quality issues; it is arguably in this area where many questions and difficulties arise. A chapter on bottled waters then follows. Although not soft drinks, they are an important and rapidly developing related market sector with many common concerns. A chapter on packaging follows. This is an essential part of our industry as liquid products must of necessity be contained in a bottle, can or other form of package and the chapter attempts to cover this wide topic with its implications for product shelf-life and consumer interaction. Later chapters cover storage and distribution, the management of consumer complaints, environmental issues and finally regulatory and statutory matters. Dealing with legislative matters in a book is always fraught with difficulty because the information is invariably out of date by the time the book is published and is, in any event, likely to cover only a limited jurisdiction. Despite
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that shortcoming, we have included a number of references to United Kingdom and EU legislation as many problems of the industry revolve around regulatory affairs. We do, however, acknowledge that there will be other countries for which the regulatory information in this book is not relevant. In whichever country the reader is based, any problem that is related to a legislative matter should, therefore, always be checked with an appropriately qualified person who can give timely and accurate advice. The authors acknowledge that there are questions and problems of a similar nature that appear in different chapters of the book. We have decided that it may be more helpful to readers to leave this degree of duplication than to always cross refer to a single, and perhaps more comprehensive, answer elsewhere. This should hopefully enable a problem to be considered in the specific context in which it arose. It will be obvious that it has not been possible to cover every conceivable problem or question that might arise in this industry but the authors hope that they have covered a sufficiently wide range of topics to make the work a valuable companion to technical staff, marketing specialists, students and those who perhaps just have a curious enquiring mind relating to soft drinks, fruit juice and bottled water industries throughout the world. Robert Hargitt Philip Ashurst
Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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List of acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1
Product development of new soft drinks and fruit juices . . . . . . . 1.1 Initial issues affecting product development . . . . . . . . . . . . . . . . . . . 1.1.1 How do I obtain the main brief for a new or modified product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.2 What factors need to be considered at an early stage and how much data is needed before development starts? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.3 How much technical input should there be in deciding the brief? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.4 What are the main issues affecting the development of a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.5 What timescale should be allowed for the development of a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.6 What microbiological tests should be carried out on a developmental product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 The marketing brief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.1 Who should be the main driver in preparing the marketing brief: the technical or the marketing department? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.2 How detailed should the product brief be? How much technical and marketing information should be provided? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 1 1 2 2 3 3 4 5 5 5
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Contents 1.2.3 Do special regulations exist for sports drinks? What is an isotonic drink? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.4 Are there any special regulations for drinks for babies? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.5 How often should the marketing brief be reviewed? . . . 1.2.6 What issues surround `tooth-friendly' drinks? . . . . . . . . . . 1.3 Cost constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.1 Should the initial product concept be developed without reference to cost? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.2 When should the impact of cost be assessed? . . . . . . . . . . 1.3.3 How much influence should the company accounting function have on product development? . . . . . . . . . . . . . . . . 1.3.4 How do I establish a likely selling price? . . . . . . . . . . . . . . 1.3.5 Will new capital plant be needed? . . . . . . . . . . . . . . . . . . . . . 1.4 Packaging issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.1 Should the issues of packaging be raised at the early stages of product development and how important is packaging to the product concept? . . . . . . . . . . . . . . . . . . . . . 1.4.2 What considerations should be raised in deciding the preferred packaging? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.3 What influence does packaging have on production and its costs? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.4 Can I design my own packaging? . . . . . . . . . . . . . . . . . . . . . . 1.5 Manufacturing issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.1 What are the principal limitations to be considered in the early stages of development? . . . . . . . . . . . . . . . . . . . . . . 1.5.2 How can a new product be assessed for manufacture without large-scale production? . . . . . . . . . . . . . . . . . . . . . . . . 1.5.3 When should I consider outsourcing the initial manufacture of a new product? Is contract packing a viable option? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.4 Can existing production facilities be modified? . . . . . . . . 1.5.5 Do some ingredients require special handling facilities? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.6 Can test plant data be scaled up? . . . . . . . . . . . . . . . . . . . . . . 1.6 Shelf-life prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.1 Can shelf-life be predicted? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.2 What methods are used to predict shelf-life? . . . . . . . . . . 1.6.3 What facilities do I need to conduct shelf-life tests? . . . 1.6.4 How does shelf-life impact on the business plan? . . . . . . 1.6.5 Should shelf-life be continually assessed after a product is in regular production? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7 Assessing consumer reactions to new products . . . . . . . . . . . . . . . . 1.7.1 How can likely consumer reactions to new products be best assessed? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 6 7 7 7 7 8 8 9 9 10 10 10 10 11 12 12 12 12 13 13 14 14 14 15 15 16 17 17 17
Contents 1.7.2 Can I outsource market research and, if so, to whom? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7.3 How long should a new product be given to find its place in the market? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7.4 How can I predict likely sales volumes? . . . . . . . . . . . . . . . 2
Ingredients in soft drinks and fruit juices . . . . . . . . . . . . . . . . . . . . . . . 2.1 Water as an ingredient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.1 How much does water quality affect soft drinks? . . . . . . 2.1.2 Should water treatment be installed in a soft drink or fruit juice processing plant? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.3 Is there an ideal specification for water to be used in soft drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.4 How frequently should water testing take place? . . . . . . 2.1.5 Can I use natural mineral water or spring water to make a soft drink or reconstituted fruit juice, and can I bring these waters in by tanker? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.6 Is a `flavoured' water a soft drink or a water? . . . . . . . . . 2.2 Fruit components as ingredients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.1 What types of fruit components are readily available and what are the differences between juices, comminutes, fruit pureÂes and fruit extracts? . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.2 What, if any, special processing is needed for packed fruit juices and products containing fruit ingredients? . . . . . . . 2.2.3 How do I calculate the fruit content of a product when using a concentrated fruit preparation? . . . . . . . . . . . . . . . . . 2.2.4 What factors do I need to consider in the specification for fruit ingredients? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.5 What kind of problems can arise from the use of fruit in a soft drink? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.6 Are all exotic fruits permitted in beverages and how can I establish which are allowed? . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.7 Can a product be labelled `sugar free' if only fruit components are added? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.8 How can I be sure of the authenticity of fruit materials? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Carbohydrate sweeteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.1 What carbohydrate sweeteners are available for use in soft drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.2 How do other sweeteners compare with sucrose? . . . . . . 2.3.3 Do different sweeteners affect product stability? . . . . . . . 2.3.4 How do different sweeteners affect production and process control? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.5 What are `fruit extracts' and how should they be labelled? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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2.3.6 Are special technical or process requirements needed to enable the handling of bulk carbohydrates in dry or syrup form? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.7 What typical specifications should I apply to carbohydrates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4 Intense sweeteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4.1 How do I select the right intense sweetener for my product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4.2 Do different intense sweeteners have different taste profiles? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4.3 What kind of stability can I expect from intense sweeteners? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4.4 Why does aspartame require special labelling? . . . . . . . . 2.4.5 Are there any natural intense sweeteners? . . . . . . . . . . . . . 2.4.6 Why are intense sweeteners blended? . . . . . . . . . . . . . . . . . . 2.4.7 Why has the use of cyclamate declined? . . . . . . . . . . . . . . . 2.4.8 Can I use sugar alcohols such as xylitol? . . . . . . . . . . . . . . 2.5 Flavourings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5.1 What types of flavourings are available and why are they used? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5.2 How are flavourings best assessed in the development laboratory? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5.3 What kind of shelf-life do flavourings have? . . . . . . . . . . 2.5.4 How do flavourings affect product stability? . . . . . . . . . . . 2.5.5 How much interaction can I expect between flavourings and other ingredients? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5.6 What different types of flavourings are available? . . . . . 2.5.7 How do specific ingredients that add flavour, such as quinine and caffeine, have to be labelled? . . . . . . . . . . . . . 2.5.8 Do I need approval for `novel' flavours? . . . . . . . . . . . . . . 2.6 Colourings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6.1 What factors are to be considered in selecting natural or artificial colourings? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6.2 How much added colour can I expect from fruit or other components? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6.3 Are there any ingredients that will give colour to a product but do not require a label declaration as such? 2.6.4 What are the main factors that affect the stability of colour in a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.6.5 There are several different types of caramels; what are the differences between them? . . . . . . . . . . . . . . . . . . . . . . . . . 2.6.6 Why are the media so critical of colourings? . . . . . . . . . . 2.7 Preservatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7.1 What factors should be considered in deciding whether to use any preservative? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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2.8 2.9
3
2.7.2 How can the right preservatives be selected for a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7.3 Does the use of a preservative in a product mean that it does not need to be pasteurised? . . . . . . . . . . . . . . . . . . . . . 2.7.4 Do preservatives in product deteriorate with time? . . . . 2.7.5 Does dimethyl dicarbonate (DMDC) (trade name Velcorin) have to be declared as a preservative? . . . . . . . 2.7.6 Why will some local authorities not purchase products containing benzoic acid? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7.7 Why may both sorbic and benzoic acids be unsuitable for tea drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nutraceutical ingredients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.8.1 What are nutraceutical ingredients, how can I use them and how should they be labelled? . . . . . . . . . . . . . . . . . . . . . . Miscellaneous additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9.1 What miscellaneous additives can I use in a product and what functions do they perform? . . . . . . . . . . . . . . . . . . 2.9.2 If an additive is used as a process aid, does it have to be declared on the label? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.9.3 Is there an industry standard for carbon dioxide? . . . . . . 2.9.4 How is carbonation measured? . . . . . . . . . . . . . . . . . . . . . . . . . 2.9.5 How are additives in ingredients declared? . . . . . . . . . . . . 2.9.6 Can I use antifoam? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manufacture of soft drinks and fruit juices . . . . . . . . . . . . . . . . . . . . . 3.1 Ingredient sourcing and storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.1 How much responsibility for ingredient quality can be transferred to the supplier? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.2 What storage conditions should I use for ingredients? . 3.1.3 Are compound ingredients best outsourced or mixed locally? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.4 What are the best ways of storing carbon dioxide, sugar, fruit juices, flavours and other additives? . . . . . . . 3.1.5 How do I avoid product `drift'? . . . . . . . . . . . . . . . . . . . . . . . . 3.1.6 What standards should I operate to and what standards should I demand from my suppliers? . . . . . . . . . . . . . . . . . . 3.1.7 Do some ingredients demand special production plant? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1.8 What do I need to specify on a supplier contract? . . . . . 3.1.9 Do I need to audit suppliers? . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Mixing, compounding and related problems . . . . . . . . . . . . . . . . . . . 3.2.1 What type of mixing plant is ideal for soft drinks? . . . . 3.2.2 Is there an ideal order of addition for ingredients? . . . . . 3.2.3 If undissolved materials remain in the syrup mix, what action should be taken? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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3.3
3.4
3.5
3.6
4
3.2.4 What steps should be taken to minimise the introduction of air into the product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.5 Why do I have an oily film on the surface of my syrup? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.6 What is the most likely cause of white flecks on the surface of my syrup during manufacture? . . . . . . . . . . . . . . 3.2.7 Can I make milk/yoghurt and fruit juice drinks in my soft drinks plant? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.8 Should I dissolve ingredients prior to addition? . . . . . . . . 3.2.9 Should turbulence be avoided during mixing? . . . . . . . . . 3.2.10 How much automation should be installed? . . . . . . . . . . . . 3.2.11 Are there any special manufacturing issues that apply to pure fruit juices? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pasteurisation, homogenisation and related issues . . . . . . . . . . . . . 3.3.1 When is pasteurisation necessary? . . . . . . . . . . . . . . . . . . . . . 3.3.2 What pasteurisation conditions are needed and how can these be calculated? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.3 When is it desirable to homogenise a product? . . . . . . . . 3.3.4 What are the best types of pumps to use? . . . . . . . . . . . . . 3.3.5 Are changes to the taste or appearance of a product likely as a result of pasteurisation? . . . . . . . . . . . . . . . . . . . . Filling operations and related issues . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.1 Do different filler types affect product quality? . . . . . . . . 3.4.2 What regular quality checks should be made on fillers? 3.4.3 What is a typical cleaning regime for a filler? . . . . . . . . . 3.4.4 At what temperature should products be filled? . . . . . . . . 3.4.5 Why do some products froth (fob) and how can this be avoided? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.6 What is the average fill system (e-mark)? . . . . . . . . . . . . . 3.4.7 How should I deal with broken bottles in the filler? . . . 3.4.8 How do I ensure the absence of foreign bodies in product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.9 What hygiene requirements apply to manufacturers of soft drinks and fruit juices? . . . . . . . . . . . . . . . . . . . . . . . . . . . . Secondary packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5.1 How does secondary packaging affect product quality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5.2 What protection is needed from secondary packaging? Finished product storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.6.1 What are the ideal conditions for product storage? . . . . 3.6.2 What product problems can occur during storage? . . . . . 3.6.3 When do products need to be quarantined? . . . . . . . . . . . .
Quality issues in soft drink and fruit juice processing . . . . . . . . . . 4.1 Ingredient quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4.2
4.3
4.4
4.1.1 How much deviation from ingredient specification is needed to cause a noticeable alteration of product quality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.2 What are the key parameters that I should evaluate to assess ingredient quality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.3 A `floc' forms in an otherwise clear soft drink; where should I look for the likely cause? . . . . . . . . . . . . . . . . . . . . . 4.1.4 When can I switch to an alternative supply source without extensive testing? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.5 How do I ensure consistent product quality and avoid drift? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.6 How do I specify a flavour? . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.7 How do I deal with variations in natural ingredients, particularly fruit juices from different sources? . . . . . . . . Ingredient interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.1 Are there any ingredients that are likely to cause unwanted interactions with others? . . . . . . . . . . . . . . . . . . . . . 4.2.2 What are the most likely effects of ingredient interactions? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 How are the conditions of storage likely to affect ingredient interactions? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.4 Can I use both benzoic and ascorbic acids in the same product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.5 What are the ICBA guidelines on benzene formation and where are they available? . . . . . . . . . . . . . . . . . . . . . . . . . . Ingredient specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.1 Do I need to check every batch of ingredient against specification? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.2 How meaningful are specifications for natural ingredients that may be standardised to only one or two parameters (e.g. concentrated juices)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.3 What are the key issues that I need to have in mind when considering ingredient specifications? . . . . . . . . . . . 4.3.4 Is it possible to specify flavour character? . . . . . . . . . . . . . 4.3.5 How much variation should I allow in natural materials? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Problems during manufacture and safety issues . . . . . . . . . . . . . . . 4.4.1 A process worker has added too much of one ingredient; how is this best dealt with? . . . . . . . . . . . . . . . . 4.4.2 The final volume of a product has been exceeded; how can the situation best be resolved? . . . . . . . . . . . . . . . . 4.4.3 A batch of product has been made up but not bottled off. It is then noticed that a preservative (or other ingredient) has not been added. Can the missing ingredient simply be added to the bulk product? . . . . . . .
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4.5
4.6
4.7
4.4.4 The electrical supply has failed during flash pasteurisation; is it necessary to repasteurise the whole batch? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.5 What actions generally need to be taken during a stop in production, particularly with respect to products in the pasteuriser? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.6 Is an HACCP system now a legal requirement and how do I set one up? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.7 How much record keeping is required and for how long should records be kept? . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.8 What regular checks should be carried out on a tunnel pasteuriser? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.9 What are the main risks of contamination and how can I check for these? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Colour and appearance changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5.1 A normally clear product becomes cloudy on storage; what are the likely causes? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5.2 A product displays a `ring' at its upper surface; what is this likely to be and how can it be resolved? . . . . . . . . 4.5.3 What are the causes of product colour fading? . . . . . . . . . 4.5.4 (a) A concentrated soft drink that is normally cloudy separates into a clear upper layer and a dense lower layer of pulp; what is the likely cause and how can it be resolved? (b) A concentrated soft drink has formed a gel on storage; what is the likely cause and how can it be resolved? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5.5 Fruit pulp forms a plug or mat on top of the product; what causes this and how should it be dealt with? . . . . . 4.5.6 How can emulsion stability be best evaluated? . . . . . . . . Flavour deterioration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.1 What factors affect flavour deterioration? . . . . . . . . . . . . . . 4.6.2 How is the flavour profile of a product best assessed? . 4.6.3 What kind of sensory tests can be used to evaluate flavour changes in a product? . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.4 Apart from the obvious source (i.e. the flavouring), which ingredients are most likely to cause flavour problems? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.5 Where can I get help in determining the likely origin of an unusual flavour taint? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6.6 How important is the removal of chlorine in process water in avoiding flavour defects? . . . . . . . . . . . . . . . . . . . . . 4.6.7 How can packaging influence flavour deterioration? . . . 4.6.8 What kind of flavour deterioration can arise from microbial infections? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Packaging interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4.8
4.9
4.7.1 What problems are most likely to arise when plastic packaging of any kind is used? . . . . . . . . . . . . . . . . . . . . . . . . 4.7.2 When cans are used, what are the most likely interactions? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7.3 What special problems, other than physical contamination, are possible if glass packaging is used? 4.7.4 What issues are likely to arise when flexible packaging is used? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7.5 Do aseptic packs have any particular problems associated with them? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7.6 How much attention should I pay to the specification of packaging material? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7.7 What are the major packaging problems? . . . . . . . . . . . . . . 4.7.8 Why are product shelf-lives shorter in PET packages when compared with glass, cans or TetraPak/ Combibloc? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.7.9 What is the best plastic in which to pack still drinks? . Microbiological problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.1 What makes one soft drink more susceptible to microbial spoilage than another? . . . . . . . . . . . . . . . . . . . . . . . 4.8.2 What are the organisms that I need to be particularly aware of? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.3 Can soft drinks become contaminated with pathogenic organisms? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.4 What are the early signs of microbial contamination? . 4.8.5 How do I find the likely source of microbial contamination in a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.6 What value does a period of quarantine storage have? . 4.8.7 How can I best ensure that the water I use does not become a source of contamination? . . . . . . . . . . . . . . . . . . . . 4.8.8 An equipment breakdown causes a delay of several hours before a product can be packed off; does this situation pose a serious threat to the microbiological condition of the product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.9 Why is mould contamination not a problem for carbonated drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.10 What is Zygosaccharomyces bailii and why is it such a problem? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8.11 I know that most product spoilage results from yeast and/or mould contamination; what bacterial infections might affect soft drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shelf-life issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9.1 What are the main factors affecting the shelf-life of a product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9.2 Can the shelf-life of a product be accurately predicted?
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Contents 4.9.3 What does the term `shelf-life' of a product actually mean? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9.4 Should the shelf-life of products be monitored on a regular basis? If so, how should this be done? . . . . . . . . . 4.9.5 Why do products need such a long shelf-life and how can this be maximised? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.9.6 How does packaging affect shelf-life? . . . . . . . . . . . . . . . . .
5
Bottled waters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1 Legislation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1 What UK legislation applies to bottled waters? . . . . . . . . 5.1.2 What are the differences between natural mineral water, spring water and table water? . . . . . . . . . . . . . . . . . . . 5.1.3 How should different waters be labelled? . . . . . . . . . . . . . . 5.1.4 What licences are required to extract and bottle water? 5.1.5 What testing regime do I need to put in place? . . . . . . . . 5.1.6 Do I need any discharge consents if I am only bottling water? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.7 What other ingredients can I add to bottled waters? . . . 5.2 Water extraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 How much information do I need about my borehole and how much water can I extract? . . . . . . . . . . . . . . . . . . . . 5.2.2 How does my borehole need to be protected? . . . . . . . . . 5.2.3 How close to the source do I need to bottle? . . . . . . . . . . 5.2.4 How can I establish whether the water from my borehole is of consistent quality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.5 What action should be taken if the quality of water from a borehole suddenly drops? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.6 Can extraction from a borehole be intermittent? . . . . . . . 5.3 Water treatment and bottling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.1 What treatments can I apply to different water sources? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.2 Can I bottle water and soft drinks in the same plant? . . 5.3.3 What is the best way to sterilise a water bottling plant? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.4 Do I need to take any special precautions in a water bottling plant? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 Quality issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.1 What are the most likely appearance defects affecting bottled waters? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.2 What are the most likely sources of taints in bottled waters? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.3 What kinds of organisms will grow in bottled waters? . 5.4.4 Does carbon dioxide added to bottled waters need to be of special quality? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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5.5
6
5.4.5 What shelf-life can be expected from bottled waters? . . 5.4.6 Do I need special closures or packaging for bottled waters? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Storage and distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.1 Do bottled waters require any special storage conditions? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Packaging, storage and distribution of soft drinks and fruit juices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1 Selection of packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.1 What factors should be taken into account when the selection of packaging is under consideration for a new product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.2 How do I evaluate the likely performance of different types of plastic packaging? What factors should I consider? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.3 What do I need to look out for when selecting the closure? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.4 Where can I go for more help with packaging problems? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1.5 Do cans pose a risk of metal pick-up to soft drinks? . . 6.1.6 What special problems are likely to be associated with the use of returnable glass bottles? . . . . . . . . . . . . . . . . . . . . . 6.1.7 How does packaging relate to consumer expectations? 6.1.8 What problems can I expect from the use of cartons? . 6.1.9 Are there any guidelines for sports closures? . . . . . . . . . . 6.2 Packaging defects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.1 What are the most likely defects associated with glass bottles? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.2 Are cans likely to show particular defects? . . . . . . . . . . . . 6.2.3 What inspection regime do I need to put in place to minimise the risk of any defective container reaching the consumer? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.4 Are there any types of defects that pose a special risk to the consumer? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.5 What is the best way to print `best before' (BBE) dates on containers? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2.6 Are there any guidelines relating to clear labelling? . . . 6.3 Problems during filling and packaging operations . . . . . . . . . . . . . 6.3.1 What are the most likely problems that can arise during packaging with any of the packaging types in regular use? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.2 Do such operational problems usually pose a threat to the integrity or safety of the product? . . . . . . . . . . . . . . . . . .
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6.4
6.5
6.6
7
6.3.3 What process quality checks should be in place to minimise the consequential problems of packaging defects? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3.4 Do small changes in packaging need extensive trials? . 6.3.5 At what temperature should containers be after filling? 6.3.6 What are appropriate carbonation levels for different products and container types? . . . . . . . . . . . . . . . . . . . . . . . . . . Post-filling defects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.1 What are post-filling defects and how do they arise? . . 6.4.2 What special problems are posed when filled and closed packs are subject to tunnel pasteurisation? . . . . . . . . . . . . . 6.4.3 Are there any particular problems that can arise after secondary packaging is applied? . . . . . . . . . . . . . . . . . . . . . . . 6.4.4 What causes TEBO and what is the function of vertical slots in the threads of bottles containing carbonated drinks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.5 What is stress corrosion of cans and how may it be prevented? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Storage conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5.1 How can I monitor the range of conditions likely to be experienced by my products between manufacture and consumption? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5.2 What level of handling abuse do I need to consider when specifying secondary packaging? . . . . . . . . . . . . . . . . 6.5.3 How quickly, in the event of a product recall, can I trace and withdraw a particular batch of product from storage and distribution? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5.4 Are there particular storage conditions for my products that need to be avoided? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5.5 What effect are strong aromas likely to have on stored products? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Distribution problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.1 How much do I know about the distribution network that handles my products? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.2 How much control do I have over the distribution network? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.3 Are there places where products are likely to be distributed out of order? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.4 How can damage during distribution be minimised? . . .
Handling consumer complaints about soft drinks and fruit juices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1 Recording and handling consumer complaints . . . . . . . . . . . . . . . . . 7.1.1 What system should be in place for handling complaints? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
142 143 143 144 145 145 145 146 147 147 148 148 148 149 149 150 150 150 151 151 152 153 153 153
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7.1.2 How should complaints be classified? . . . . . . . . . . . . . . . . . 7.1.3 Do customer complaints need to be justified? . . . . . . . . . 7.1.4 What procedures should a manufacturer have in place to identify the likely cause of complaints and any corrective action necessary to prevent their recurrence? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1.5 How quickly should a manufacturer respond to complaints? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1.6 How can situations likely to result in a product recall be identified? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Traceability systems and crisis management . . . . . . . . . . . . . . . . . . . 7.2.1 How effective should a traceability system be? . . . . . . . . 7.2.2 Who needs to be in a crisis management team to deal with any major incidents? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.3 When is it necessary to obtain expert assistance in the event of a contamination incident? . . . . . . . . . . . . . . . . . . . . . 7.2.4 Where can further assistance be obtained to deal with complaints of a serious nature? . . . . . . . . . . . . . . . . . . . . . . . . 7.2.5 Is it advisable to have a public relations advisor to deal with serious complaints? . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.6 When do product problems require that enforcement authorities be informed and when should a product recall be instituted? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.7 What should be regarded as a complaint and what is a typical level of consumer complaints? . . . . . . . . . . . . . . .
154 155
Environmental issues in the manufacture of soft drinks and fruit juices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1 How do I find out about which regulations and consents apply to my business? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2 What are the major sources of waste from my business? . . . . . . 8.3 Are all the necessary consents in place for me to discharge effluent? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4 Am I discarding valuable ingredients (such as sugar residues)? If so, can I recover all or part of them? . . . . . . . . . . . . . . . . . . . . . . . 8.5 Am I meeting my obligations under the Packaging Waste Regulations? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.6 Is there anything I can do to recycle any of my packaging components or to use recycled components? . . . . . . . . . . . . . . . . . . 8.7 Can I use recycled PET? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.8 What is IPPC and does it relate to my business? . . . . . . . . . . . . . . 8.9 What is the Climate Change Levy and can I claim exemption? 8.10 Is my business affected by WEEE? . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.11 Do my containers have to be recyclable? . . . . . . . . . . . . . . . . . . . . . . 8.12 Are coloured plastics recyclable? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
155 156 156 157 157 158 158 159 160 160 161 162 162 162 163 163 163 164 164 164 165 165 165 165
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Regulatory issues relating to soft drinks and fruit juices . . . . . . . 9.1 How much information should be available in product formulations? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 How can compliance with legislation in markets other than that for which the product was originally designed be confirmed, and how can such information be kept up to date? . . . . . . . . . . . . 9.3 How can the fruit or juice content of a product be calculated for the purpose of declaring the QUID value or for confirmation of a claim? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.4 How important is it to be able to access historical formulas? . 9.5 Are current product labels accurate, up to date and legal? . . . . . 9.6 Should the local Trading Standards Department (or other relevant enforcement authority) be involved in approving product labels? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.7 How can nutritional claims be sustained, and how should nutritional data be obtained? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.8 What does a responsible manufacturer have to do to keep up to date with statutory requirements? . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.9 Does allergen labelling apply to soft drinks? . . . . . . . . . . . . . . . . . . 9.10 What are the main statutory requirements with which a beverages manufacturer must comply in the United Kingdom? . . . . . . . . . . 9.11 What does a manufacturer need to be aware of when wishing to make nutritional claims for a product as listed in EU Regulation 1924/2006? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.12 How is the nutritional value of a product calculated? . . . . . . . . . 9.13 Are there any special health and safety issues that relate to soft drinks manufacture? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
167 167 168 168 169 170 170 171 172 172 173 174 175 176
References and further reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1 Product development of new soft drinks and fruit juices Abstract: This chapter lists and answers key questions arising during product development of soft drinks and fruit juices. It reviews such issues as the marketing brief, cost constraints, manufacturing and packaging issues, shelf-life prediction and ways of assessing consumer reactions to new products. Key words: soft drinks, fruit juices, product development, marketing brief, shelf-life prediction, consumer reactions.
1.1
Initial issues affecting product development
1.1.1 How do I obtain the main brief for a new or modified product? Concept generation can be carried out by either marketing or technical departments, but a combination of both is usually most successful. Identification of a market need or trend will lead to product ideas. Ideally the product will have a `unique selling point' (USP) which will be attractive to consumers and allow the product to stand out against those of competitors. There are specialist agencies and consultants that use techniques to engender new ideas and radical product concepts which can then be honed into commercially viable and practical developments. Developments can be modifications or extensions of existing product ranges, e.g. a new or improved flavour or a completely new product concept. The great majority of developments fall into the first category, totally new concepts being relatively rare. A sudden spate of developments can be generated by the introduction of a new or modified ingredient such as the sweetener sucralose, or the `super fruit' goji berries. Consumer and market research can be used to identify so-called `gaps in the market', which could be new flavours, low-calorie or sugar-free variants, new
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packaging formats, new bottle sizes, wide-mouth bottles, sports caps, multipacks, etc. The development of a completely novel drink concept, sometimes termed `blue skies research', offers potentially greater rewards if successful but involves inherently greater risk, greater cost and longer development time. 1.1.2 What factors need to be considered at an early stage and how much data is needed before development starts? The fundamental questions are: · Do consumers like the product enough to buy it? · Can it be manufactured and supplied at a price that they are prepared to pay? Whilst a broad brief allows scope for the product developer's creativity, a tight initial brief leads to more focused and rapid development. It is preferable to direct the creative input into the development of a comprehensive brief. Factors to be considered are: · Market position Is the product a premium adult drink for sale in bars or a low-cost children's drink for sale in discount retailers? Identifying the target market is a crucial factor. A product targeted at teenage boys would be significantly different from one targeted at 20+ females. Is the product for refreshment only or does it have additional selling points, e.g. fruit juice content, antioxidants, vitamins, etc.? · Packaging format Is the product to be in bottles (glass or PET) or in cans or cartons? · Technical constraints Is the product still or carbonated, does it require pasteurisation, is it to be low calorie, is it to have only natural colours and flavours, etc.? · Production constraints Can the product be manufactured on existing company production facilities or will expensive production equipment need to be installed? Can production be contracted out to another manufacturer easily? 1.1.3 How much technical input should there be in deciding the brief? Technical input is vital, if only to identify all the issues which need to be overcome during development. It must be established that all aspects of the proposed product and its manufacture are technically viable and identify the issues that need to be resolved. Technical issues need not necessarily limit creativity or product novelty but they must be factored into the development programme. The whole supply chain from raw material supplies and handling to product distribution and storage should be considered (see Section 1.1.4). Technical input must identify all the issues to be resolved during the course of development, and an estimate of the difficulty and time required for solving these issues can be made to enable a draft timetable or development programme
Product development of new soft drinks and fruit juices
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to be drawn up. It must be remembered that any such timetable is only an educated guess as it is impossible to know in advance how long a problem will take to solve. It is therefore essential to review the programme regularly and to `flag up' any delays or target dates missed. 1.1.4 What are the main issues affecting the development of a product? · Raw materials supply Is the material available of the right quality and adequate quantity? If a fruit material is required in significant quantity, when is it in season? If a non-standard fruit material is needed in large quantities, it may not be possible to obtain a sufficient quantity outside the season. This will be especially true if the material has a tight specification for colour, purity, etc. rather than being a standard commodity material. · Raw materials handling Are there special requirements for storage and handling of any new materials? · Packaging Will standard packaging be used or will a new or modified format be required? · Formulation Is the drink just a new flavour variant in an existing product range or a completely new product using new raw materials and new processing? What shelf-life is needed and will the product and packaging survive likely storage and distribution conditions? The physical and microbiological stability of the product must be assured under all likely circumstances. How much stability and shelf-life testing will be required? Will any new or modified production plant be required? Can a suitable contract packer be located? · Consumer acceptability Will sufficient consumers buy the product? How much consumer research and market testing will be required? · Cost/Price Can the product be manufactured and delivered at a price the consumer is willing to pay? How much is the consumer willing to pay? 1.1.5 What timescale should be allowed for the development of a product? The timescale is dependent upon the nature of the development to be undertaken. The unknowns should be identified and estimates made of how long the evaluation of each will take. In any major development be aware of the likelihood of `unknown unknowns'. Those are issues which you are unaware that you do not know. It is essential to draft an activity timing plan and indicate key decision points and dates. Regular reviews will identify whether the development is falling behind schedule and the plan can be modified as necessary. Some developmental stages can be run concurrently but some must of necessity be consecutive. Where possible, be certain to include all options in the evaluation. It is most undesirable to discover after several months of development that for some reason the test product is not satisfactory and further options need to be evaluated. The time needed to develop and evaluate a new product depends on the degree of novelty, and whilst testing can be accelerated up to a point (see
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Section 1.6) it is risky to launch a product without evaluating it for at least a large part of its shelf-life. It is also impossible to take into account all possible variables which can arise in the production process and in the sourcing of raw materials. It is always preferable to build up production slowly and monitor performance under real conditions rather than launch into full-scale operations without adequate testing. A test marketing followed by a roll-out to full-scale operations is always desirable in order to overcome any `teething problems' which inevitably occur during the introduction of a new product. Unfortunately there is always commercial pressure for a development to be carried out in the minimum possible time. Frequently a product must be launched for a predetermined deadline; for example, many products are launched in early spring in order to be established in the market for the peak sales period. In such instances a risk/benefit assessment must be conducted and the commercial implications clearly understood before a decision is made to reduce the development time and shorten the testing period. 1.1.6 What microbiological tests should be carried out on a developmental product? Soft drinks are high-acid products, generally having a pH < 4, and therefore, provided the normal industry hygiene precautions are taken, harmful organisms (pathogens) are not a problem. However, drinks having a pH > 4 such as some tea drinks, and particularly vegetable juices, are at much greater risk and must be handled as low-acid foods. These require more robust hygiene conditions and much more severe pasteurisation conditions, e.g. 120 ëC for up to 45 seconds. Low-acid vegetable juices, for example carrot juice, are susceptible to dangerous pathogens such as Clostridium botulinum and must be handled as high-risk foods. Standard (high-acid) soft drinks are subject to spoilage by yeasts, moulds and bacteria. Moulds are inhibited by high carbon dioxide (CO2) levels and are not a problem in carbonated drinks. The drink and its processing should be subjected to challenge testing by a range of organisms likely to occur in the raw materials and processing plant at and above the levels they are likely to occur. Samples should be inoculated with actively growing organisms in order to replicate real situations. Dormant organisms may not provide a true picture of the risk. The inoculated samples are then processed and stored at ambient and elevated temperatures and their microbiological status evaluated periodically. If the drinks are designed to be distributed and sold via the cold chain then they would be tested under those conditions and at ambient temperature to replicate correct storage and abuse conditions. Extensive microbiological testing would only be undertaken for new products or ones where any proposed modification is likely to impact upon the microbiological risk. For susceptible products it is essential to ensure that the hygienic performance of the production line is capable of maintaining the desired standards.
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Below are three examples of specific organisms which have proved to be major sources of problems to the soft drinks industry due to their particular characteristics and of which developers should be aware: · Zygosaccharomyces baillii This yeast is resistant to both benzoate and sorbate preservatives and will cause fermentation problems if it is present in fruit juice supplies. It is most likely to be found in tropical juices. · Alicyclobacillus acidoterrestris This bacterium is a thermophile and the spores are extremely resistant to heat. It will survive normal juice pasteurisation conditions and cause an unpleasant flavour in the resulting fruit juice. · Penicillium roquefortii This commonly occurring mould (which is found in many blue cheeses) will metabolise sorbic acid preservative to produce 1,3pentadiene which has a pungent aroma similar to that of diesel fuel. It is inhibited by CO2 but has been a major source of problems in sorbatepreserved still drinks. Some other strains of Penicillium moulds are also a problem.
1.2
The marketing brief
1.2.1 Who should be the main driver in preparing the marketing brief: the technical or the marketing department? The soft drinks industry in general is marketing led and, whilst it is important that the technical and marketing functions work closely together, it is usual for marketing to take the lead. Any new product must appeal to the consumer. It is the responsibility of the marketing department to identify `gaps in the market' and new consumer trends. Some developments are carried out for technical reasons, for example to improve product stability, to improve production efficiencies, to reduce costs or to introduce natural flavourings or colourings in order to make a claim. These would, of course, be technically led. 1.2.2 How detailed should the product brief be? How much technical and marketing information should be provided? Sufficient marketing and technical detail should be provided to give the new product developers a firm `steer' but still allow a degree of creativity. A marketing team should be able to define a new product development in considerable detail from their research findings, specifying the target consumer profile and the generic drink type, for example a fruit-based drink targeted at 18±30-year-old females for sale in bars, or a refreshing energy drink in cans targeted at teenage boys. Some technical detail may be specified for desired attributes, e.g. no added sugar, or with added vitamins, etc., about which claims may be made.
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1.2.3 Do special regulations exist for sports drinks? What is an isotonic drink? There are currently no specific regulations for sports drinks. In 2004 the EU Commission published a `Draft Directive on foodstuffs intended to meet the expenditure of intense muscular effort, especially for sportsmen', generally known as the Sports Foods Directive. However, the document was never progressed and enacted. At the time of writing the position of sports drinks is under discussion. The Commission could either introduce specific sports drinks regulations under the PARNUTS Framework Directive (89/398/EC) or make provision under the nutrition and health claims regulations (1924/2006). At the time of writing it appears that it will be the former. This will enable claims to be made referring to the action of the sports drink. Sports drinks can be formulated in three ways in order to perform three specific functions relating to energy and hydration. The two major requirements for athletes expending energy are carbohydrates (sugars) and water. The three categories of sports drinks are as listed in the following table:
Hypotonic Isotonic Hypertonic
Carbohydrate (g/100 ml)
Osmolality (mOsmo/kg)
<3 6±8 >15
<270 270±330 >330
· A hypotonic drink is intended for rehydration and contains only low levels of carbohydrate (sugars) and electrolytes (minerals, predominantly sodium). The presence of carbohydrate and sodium at low levels speeds the adsorption of water by the body, maximising rehydration. · An isotonic drink contains glucose and sodium at similar levels to those found in the body. This maximises the rate at which glucose (energy) is taken up by the body. · Hypertonic drinks contain high levels of carbohydrate and minerals to replace those used during prolonged strenuous exercise. 1.2.4 Are there any special regulations for drinks for babies? Drinks specifically designed for children aged 36 months or less are subjected to many separate regulatory requirements. (Note: in legislation, babies are less than 12 months old and infants are less than 36 months old.) However, there are no specific regulations within the EU, only special provisions laid down within many regulations. The EU Directives on Sweeteners, Colours and Miscellaneous Additives prohibit the use of these additives in drinks designed for children aged under 36 months. A short list of additives which may be used in products for infants is listed in the Miscellaneous Additives Regulations (96/52/EC). In addition to provisions
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for additives there are special provisions for certain contaminants such as pesticides and mycotoxins. For example, the maximum limit for Patulin (a mycotoxin produced by mould) in apple juice is 50 g/litre, whereas in apple products aimed at babies and infants the limit is 10 g/litre. 1.2.5 How often should the marketing brief be reviewed? A timing schedule/development programme should be drawn up listing all the activities required in the development, and key decision dates arising. This must be closely monitored in order to note any `slippage' and rescheduled if any key dates are missed. Regular reviews of progress on the development should be held. The frequency of these reviews depends upon the overall timescale, but they should be sufficiently frequent to identify any problems which could result in missing target dates and to enable early implementation of corrective actions. 1.2.6 What issues surround `tooth-friendly' drinks? Soft drinks have been associated with dental issues in two ways. Firstly, sugarsweetened drinks are cariogenic, i.e. can cause dental caries, due to acid formation caused by bacterial action on sugar in the mouth. Secondly, dental enamel will soften and dissolve slowly at a pH less than 5 and continual exposure to acid foods or drinks, having a pH less than 5, will tend to slowly remove tooth enamel. This process is known as `erosion'. Acid foods and drinks include pickles, fruits, fruit juices and soft drinks. However, there is also a reverse process known as remineralisation by which, at higher pH levels in the presence of minerals such as calcium and fluoride, the enamel can reform. Saliva also assists neutralisation of the acidity in the mouth and helps to promote remineralisation. Drinks can be designed with the pH buffered as high as possible, whilst reformulating to minimise the impact on flavour. The pH and total acidity are key characteristics of a drink's flavour. The presence of calcium in the drink also reduces the dissolution of enamel. Such drinks can be consumed with minimal dissolution of tooth enamel. Unfortunately the relatively high pH and high calcium content do tend to impact significantly on the character of the drink. `Tooth-friendly' drinks were developed and marketed in the UK by Glaxo Smith Kline (GSK) who hold many patents on the subject. Some early work was also carried out by Procter & Gamble (P&G) who also hold patents on formulations.
1.3
Cost constraints
1.3.1 Should the initial product concept be developed without reference to cost? It is useful when researching totally novel product ideas to ignore potential constraints such as production requirements and costs. This permits greater initial creativity for both technical and marketing departments. Constraints and
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their solutions can be considered after initial ideas generation. A truly novel product may be able to sustain a significant price premium, and cost should not necessarily exclude potential products. It is important, however, that the profitability of products is assessed before any launch is decided upon. New products are frequently developed by initially optimising product performance (maximising consumer preference) and then cost-reduced in order to meet financial targets. It is important to reduce costs without significantly compromising consumer acceptability of the product. 1.3.2 When should the impact of cost be assessed? The financial viability of a project must be assessed as soon as realistic estimates of costs can be obtained. This will at least provide guidance as to the viability of the product and cost estimates can be refined as the project progresses. It is important to assess the impact on costs of any changes made during the course of the development project. Additionally, the impact of the new development on existing production should be assessed. For example, if a new product requires engineering changes to handle a new pack shape, this could result in significant downtime on the production line every time there is a product change. To change a production line to run a different pack format can take up to several hours, depending upon the type of change. This would reduce the number of hours per week for which the line could run and hence increase production costs, not just for the new product but also potentially for existing products. The impact of cost on a consumer's propensity to purchase is difficult to measure. Guidance can be obtained from consumer research but can be accurately judged only under real conditions, i.e. a test market. 1.3.3 How much influence should the company accounting function have on product development? It is vital that accurate costings and financial evaluations are available during the course of development, but financial reasons alone may not be the deciding factor as to whether a development continues or not. That decision is made on a commercial basis taking into account all aspects affecting the business. For example, if a specific development will gain incremental volume that is beneficial to the overall business, it may be decided to base the price on marginal costing (i.e. exclude fully costed overheads). However, the financial consequences of such decisions must be understood as part of the business decision. Marginal costing of developments to obtain incremental business can be very dangerous, as the business is not fully recovering its true costs, and can lead to financial problems in the long term. There is a significant difference between an accounting decision and a commercial one, the latter considering a wider field of business priorities than just profit and loss. However, it has to be remembered that the company must make a profit.
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1.3.4 How do I establish a likely selling price? If the product is merely a range extension, establishing the price will be simpler. It will sell at a similar price to other products in the range, though it may be able to justify a slightly higher selling price due to its novelty value. Alternatively, it may be sold at a lower price to be more competitive. The selling price of a totally novel product is more difficult to establish as one must be able to maintain a price differential compared to competitor products on the market and achieve the desired profit margin. It is essential to define the market positioning of the product. Is it mass market or niche? Is it premium or economy? It is difficult to establish with any degree of certainty what selling price a product will be able to maintain in the real marketplace. One must also consider that competitors may reduce their prices in response to the new threat. Market sector is an important consideration. The sales price in HORECA (hotels, restaurants and catering) and in impulse outlets is higher than in supermarkets. Consumer research can be useful to establish what customers would be willing to pay, though what consumers say in response to a questionnaire is not necessarily what they will do in the real purchasing situation. Market testing under real conditions in a few stores is helpful in this respect. The product under test may be sold at a different price point in several stores to evaluate its `price elasticity', i.e. variation of sales volume with selling price. 1.3.5 Will new capital plant be needed? Every aspect of the operational requirement must be fully evaluated systematically, from the delivery, storage and handling of raw materials through processing and packaging machinery to the secondary packaging and palletisation: · Raw materials handling and storage Fruit materials could require cold or frozen storage. High-pulp juices could require positive displacement pumps and tubular pasteurisers. Stabilisers, such as pectin, could require high shear mixers for dissolution. Glucose syrups need warm storage. · Pasteurisation and microbiological issues Can the pasteuriser achieve the required conditions and are the cleaning regime and plant hygiene adequate? · Pack handling, capping and labelling Can the production line handle the pack and labels or will changed parts be required or even new plant? · Secondary packaging and palletisation Will the boxes or shrink wrapping equipment handle the new pack? Is the palletiser capable of stacking and wrapping the new pack? Production lines tend to be specific to a particular pack type and the range of sizes tends to be limited. For soft drinks, changing the height slightly is possible but changing the bottle diameter requires major modifications to the line. The more flexible a production line the more expensive and slower it tends to be. A high-speed line running at high efficiency demands just one pack. Continual
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changes have a very deleterious effect on line efficiencies. If significant pack changes are made from the existing packs, it is very likely that new capital plant will be required.
1.4
Packaging issues
1.4.1 Should the issues of packaging be raised at the early stages of product development and how important is packaging to the product concept? Packaging is critical for consumer perception. It is vital for the product's image, and the target market sector will influence pack type and design. Consumer usage must also be considered. Will the product be in a premium single-serve pack or in a large multi-serve pack? Will it be sold in HORECA outlets or in supermarkets? The type of pack can have a significant impact on the product formulation. For example, any residual sulphur dioxide (SO2) from fruit compounds must be extremely low if the fruit drink is to be packed into cans. An oxygen-sensitive flavour cannot be used in PET due to its permeability to oxygen. A carbonated product can only be packed in PET or glass bottles or cans. If a product is to be packed in a single-serve carton with a straw then its appearance is less important than if it goes into a bottle where it would be clearly visible. It can be seen that the packaging may be a critical factor and is best considered at the very start of the development process. 1.4.2 What considerations should be raised in deciding the preferred packaging? Technical issues are important, e.g. CO2 cannot be used in cartons or pouches, and if in glass the pack design must be able to resist the highest likely pressure (high pressure if in-pack pasteurisation is to be used). The bottle manufacturer will advise on this. Market positioning must be considered (see previous section). The pack type has a significant impact on consumer perception. Distinctive heavy glass bottles are often used to give products a premium image. Seemingly minor issues may become relevant, such as whether a tall elegant bottle will fit on retailers' shelves. 1.4.3 What influence does packaging have on production and its costs? Packaging has a considerable effect on cost in all areas ± product, production and distribution. As previously mentioned, the formulation may need modification depending upon pack type. The design of the packaging can have a significant effect on line efficiency and hence production cost. Packs must be able to flow freely along production lines without jamming or toppling over. Over-complex packaging can lead to lower line efficiency and hence higher production costs. Even apparently very minor changes to packaging can have
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totally unexpected effects on line efficiency. For example, changing the colour of a pack can affect its surface characteristics and impact on the way packs behave on the line. Even changing the colour of a plastic cap can affect its performance in the capper and cause application problems on the production line. If a pack requires changes to a production line in order for it to be handled, this will lead to downtime whilst engineers modify the line. This will decrease line efficiency and increase production cost. Packs should be designed so that they can all be run down the line without having to change its parameters. The cost of the pack itself has a significant impact on total cost, particularly for low-priced products. Indeed, the packaging cost frequently exceeds the ingredient cost. Packaging also has a significant impact on distribution costs. Packs are often designed with dimensions which will fit exactly onto a pallet, thereby maximising the number of packs per pallet. Being able to fit only a smaller number of packs onto a pallet increases distribution costs significantly, and distribution is a major component of overall costs. The use of shrinkwrap with only minimal or no use of board is very low-cost compared to the cost of cardboard boxes and outer packaging, though highquality cardboard packaging can give a premium image compared to shrinkwrap. 1.4.4 Can I design my own packaging? The answer to this question is yes, to a certain degree. Cans are manufactured to fixed dimensions and any modifications would be hugely expensive, but bottles (plastic or glass) which are blown into moulds can be made to meet a personalised design. Many companies have custom-designed bottle shapes, two classic examples being the Coca-Cola bottle and the Perrier bottle, which are instantly recognisable by their shape. The initial cost of designing and manufacturing bottle moulds is very high and can only be justified by a higher selling price and/or high volume sales. The package must, of course, meet all design and safety requirements. This is particularly true for glass bottles intended to hold carbonated drinks. The artwork design of cans, cartons, labels, etc., is very much at the discretion of the manufacturer. However, the printing cost escalates rapidly the more colours are employed and the printing facilities will limit the number of colours that can be used. There are legal requirements for certain information which must be included on the pack, such as an ingredients list, product name or description, best before date, content volume, etc., and these must be clearly and indelibly printed. The FSA has a guide to clear labelling available on its website, and the EU Commission is currently processing its `Food Information Regulations' due for publication in 2009 which will lay down requirements for labelling content and legibility criteria.
12
1.5
Soft drink and fruit juice problems solved
Manufacturing issues
1.5.1 What are the principal limitations to be considered in the early stages of development? The physical issues and their engineering solutions must be evaluated to identify any potential barriers to production. Each step throughout the process must be considered, for example: · Storage, handling, dissolution and mixing of raw materials and ingredients · Pasteurisation, microbiological limitations, carbonation and filling · Handling of packs, capping, labelling and secondary packaging. Any barriers to production must be identified, an engineering solution devised and costs and timescale elucidated. A commercial decision should then be taken whether to invest in the required operational changes, seek a contract packing option or abandon or change the project brief. 1.5.2 How can a new product be assessed for manufacture without largescale production? There are specialist producers of mock-up packs who will manufacture small numbers of realistic imitation bottles, cans, cartons, etc., to use for market research or consumer testing. This enables the impact of the pack, for example its on-shelf appearance, to be assessed. Tasting samples can be stored in different containers and supplied to trial consumers separately. To assess how the product will behave during the manufacturing process, one can compare all aspects of its production to existing products currently being manufactured on the plant. Where some specifications or parameters, such as viscosity or pulp content, for example, differ from current products, these can be tested on small-scale pilot plant (see 1.5.6 below). Where new or modified packaging is being introduced it is essential that this is trialled under real production conditions as, whilst one can make an educated guess, it is impossible to predict exactly how it will behave. Although reasonable assessments of product performance can be made from comparisons with similar products and extrapolation from small-scale trials, it is impossible to guarantee exactly how bulk handling will proceed without a fullscale test. Very small changes in the design or construction of equipment can have unexpected consequences. For example, a lemonade syrup may mix perfectly in one mixing tank but have separated oil floating on the surface in a different tank due to a slight difference in the design of the stirring paddles that affects the mixing pattern of the syrup. 1.5.3 When should I consider outsourcing the initial manufacture of a new product? Is contract packing a viable option? Outsourcing is a convenient method of manufacture without the requirement for major capital investment in new plant. This may be desirable for several reasons:
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· A new product can be put on the market without the need for investment in plant to establish whether it is viable. If the development is unsuccessful then no investment is lost. If the development is successful then capital investment can be justified. · Production on an existing plant can be on stream much faster than the time taken to purchase and install new manufacturing equipment, which can be 18 months or more for a substantial development. · If a factory is already operating at maximum capacity or lacks space for expansion then contract packing may be a suitable alternative, at least in the short term. · A manufacturer may for commercial reasons wish to supply a range of packaging formats but lacks the capability in-house to do them all. Small volumes of production may never justify capital investment but can be outsourced. Contract packing is often a viable option and is widely practised in the soft drinks industry. Some manufacturers do not produce their own branded products but specialise in contract packing for either retailers or other manufacturers. They operate relatively slow but flexible production facilities. Also some smaller soft drinks companies who cannot benefit from the economies of scale have closed their own factories and now have all their production contract packed. Some small soft drinks companies are simply sales and marketing operations and have never operated a factory but have always outsourced their production. 1.5.4 Can existing production facilities be modified? This is an engineering issue which must be considered on a case-by-case basis. Dedicated high-speed lines tend to be very pack specific; lines can be designed to be flexible but that usually adds to cost and reduces the line speed. Modifying equipment to handle bottles of different heights is relatively easy, but handling bottles of differing diameters is very difficult. This always requires changed parts and major modification to the line with resultant significant downtime. Likewise for cans, 250 ml and 330 ml cans of the same diameter can often be filled on the same line, but not cans of different diameters. Some flexibility can be designed into a production line, e.g. space can be left for additional or alternative packaging equipment to be installed. However, the greater the flexibility, the higher the cost. 1.5.5 Do some ingredients require special handling facilities? Many ingredients require special handling facilities, as listed below: · Frozen concentrated fruit juices require specific handling and pumping equipment. · Juices with high pulp content require tubular rather than plate pasteurisers.
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Soft drink and fruit juice problems solved
· Some powders, for example stabilisers, require high shear mixers for dissolution. · Bulk sweeteners, granulated sugar and glucose syrups require dedicated plant. · Liquid carbon dioxide must have highly specialist handling equipment. 1.5.6 Can test plant data be scaled up? Whilst pilot-scale productions do provide very useful information, care must be taken when scaling up from small laboratory or pilot plant trials to full-scale factory production, particularly when evaluating physical activities such as shear mixing and homogenisation and for packaging operations. Some research establishments, e.g. RSSL and CCFRA, have purpose-designed pilot facilities which can be hired for individual development projects. Small-scale manufacturing equipment such as plate pasteurisers, carbonators, fillers, homogenisers, mixing vessels, etc., are available from specialist suppliers to enable a small pilot facility to be constructed in order to manufacture trial volumes of new products. The equipment is manufactured specifically to replicate conditions occurring in the manufacturing processes. The cost of establishing a purposebuilt pilot plant is very high and small manufacturers may find hiring plant more cost-effective. Whilst providing a useful indication of product performance and being useful for production of samples for testing and market research purposes, there is no replacement for actual manufacture on the real plant. This is especially true for new packaging. All modifications must be trialled on the actual production plant to guarantee acceptable performance.
1.6
Shelf-life prediction
1.6.1 Can shelf-life be predicted? A reasonable estimate of the shelf-life of a product can be made by using accelerated ageing techniques and assessing the product's performance. The shelf-life is the period for which the product remains acceptable under normal storage conditions. The deterioration of a product's appearance and flavour is gradual and depends upon the storage conditions. It is a continuum and therefore the selection of cut-off date is somewhat subjective. For PET bottles the loss of carbonation must be taken into account and for small bottles it is likely to be the limiting factor on shelf-life. The rate of loss of carbonation should be <15% over a 90-day period. As stated in Section 1.6.4, a short shelf-life has significant commercial implications and there is consequently often commercial pressure for the shelflife to be as long as possible. Since deterioration of quality parameters is a subjective continuum, there is often a compromise between that predicted technically and that required by sales departments.
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1.6.2 What methods are used to predict shelf-life? Two major factors responsible for deterioration of a product and hence its shelflife are heat and light. By subjecting a new product to high levels of these factors it is possible to accelerate the rate of deterioration and thereby estimate a shelflife. The Arrhenius equation predicts that the rate of chemical reactions typically doubles for every 10 ëC increase in temperature. Therefore three months at 30 ëC is approximately equivalent to 12 months at 10 ëC. Storage at elevated temperature is the most commonly used method of assessing shelf-life. The acceleration is, however, not linear and the use of too high a temperature will provide false results. Drinks are sampled and tasted by an expert panel at regular intervals to assess the rate of deterioration. Control samples should be stored at a low temperature (4 ëC) to provide comparison with the accelerated test samples. Drinks to be sold in bottles should be tested for their light stability. Fluorescent light tubes can be purchased which emit the same spectrum of light as natural daylight and of a specified intensity. Samples can be subjected to light and tested at regular intervals to assess the rate of deterioration. Use of a certified light source ensures that the effect is repeatable and consistent. Light can affect both the taste and the appearance or colour of a drink. Drinks that are cloudy such as squashes contain an emulsion and this can be destabilised by temperature fluctuation. The resistance of a system to cloud separation can be tested by storing in a temperature cycling unit. The product is typically held at say 35 ëC for 4 hours, then at 4 ëC for 4 hours, and this cycle is repeated until the product separates. Since accelerated ageing is empirical, in all testing it is advisable to include existing products of a similar type and of known and acceptable shelf-life to provide a comparison. The samples subjected to testing should be as close as possible to the proposed production product in every respect, e.g. degree of homogenisation and pasteurisation, air content, correct packaging, etc. 1.6.3 What facilities do I need to conduct shelf-life tests? A sample production laboratory or ideally a small pilot plant should be established in order to manufacture test samples that replicate the proposed production drinks as closely as possible. A temperature-controlled warm room or cabinets that can be maintained at a range of temperatures up to about 45 ëC should be constructed. A temperature-controlled cabinet fitted with a certified daylight light source should be used to assess the impact of light exposure. Temperature control is necessary as the light source is likely to generate significant heat. Temperature cycling systems, such as large water baths, are available commercially. The facilities should be capable of handling the number of samples generated by the development. A trained taste panel should be used to assess products on test. It is important that the panel produces accurate and reproducible results. Personnel must be evaluated for their innate tasting ability before being accepted on to the panel. This ability varies considerably from person to person and some people cannot
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Soft drink and fruit juice problems solved
taste (or can only taste very poorly) certain characteristic flavour components. These people should be rejected from the panel. The performance of the panel must be monitored by inclusion of duplicate samples (to assess reproducibility) and by inclusion of spiked samples or ones with a known defect (to assess correct identification). The panel cannot be used to assess preference, only to describe and quantify characteristics. In order to evaluate the microbiological susceptibility of a new product, it is essential to have a small micro-laboratory capable of challenge-testing products with a range of organisms and to assess the cleanliness of the production plant. 1.6.4 How does shelf-life impact on the business plan? Shelf-life has an important role in the commercial viability of a product, depending on the retail channel through which it is sold. Factors such as the weather can have a marked and sudden impact upon sales. A sudden period of very hot weather can cause a dramatic increase in sales. Conversely, a cold wet bank holiday can result in sales being far below forecasts. Manufacturers produce dozens (possibly hundreds) of different drink varieties and pack types and sizes and must of necessity have a stockholding of each to meet demand. The shelf-life has a significant bearing on the ability to hold stock. Major retailers will normally require a product to have at least 75% of its shelf-life still remaining at the time of delivery. For a product with a six-month shelf-life this means that a manufacturer has six weeks from date of production to date of delivery. Production departments generally achieve much better efficiency and hence lower costs by producing longer runs less frequently. Producing short runs of drinks at frequent intervals is much less efficient because of the production downtime caused by the necessity to clean the plant between each batch, product losses at the start and end of each run, etc. Production planning is an important function within a company. It is even more important in the case of manufacturers supplying retailer `own label' products. If a retailer orders stock and the manufacturer cannot deliver then the manufacturer may be heavily penalised by the retailer for the resulting out-ofstock situation. However, if the manufacturer holds stock and the retailer does not order delivery before the 25% of shelf-life passes, then the stock must be discarded. The retailer may accept it at a discount or it may have to be destroyed (at the manufacturer's cost). There is a fine balance between levels of production and stockholding. The major retailers have a very rapid throughput of products compared to cash-and-carry and the licensed trade, which have much longer and slower distribution chains. It is impractical to supply soft drinks having relatively short shelf-lives through slow-moving distribution channels. If, for whatever reason, branded products are still in the distribution system as they approach their sellby date, a commercial decision must be taken whether or not to sell them into the market at a heavy discount.
Product development of new soft drinks and fruit juices
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1.6.5 Should shelf-life be continually assessed after a product is in regular production? It is important to monitor the performance of drinks in regular production to ascertain whether they perform as well as was predicted by the development trials. If, for example, a product is oxidising more than was anticipated, resulting in excessive staling of the flavour or browning of the colour, then steps can be taken to improve matters, e.g. an anti-oxidant (ascorbic acid) can be added or the production process modified by de-aeration and use of a nitrogen blanket. The frequency of monitoring would be decreased with time as the product became more established and confidence improved. Routine retention samples from production, and samples obtained randomly from the market, can be inspected to ensure that performance is acceptable. This enables both the intrinsic stability of the product formulation to be evaluated and also the effect of real distribution and storage conditions to be monitored. If the shelf stability is not as good as expected then modifications can be made to the flavour system, packaging or production process to achieve the desired improvement. Alternatively it may be necessary to reduce the shelf-life although, as seen in the previous section, this is likely to have a significant commercial impact on the product.
1.7
Assessing consumer reactions to new products
1.7.1 How can likely consumer reactions to new products be best assessed? During development and for comparative flavour testing, many development laboratories use a panel of trained tasters. These staff are assessed for their innate tasting ability and are trained to recognise and identify a large range of flavours. It is very difficult for an untrained person to accurately describe a flavour in words. A scientific quantitative description of a product is, however, very different from a preference assessment by consumers. Like an opinion poll prior to an election, a consumer preference measurement depends on the number of people surveyed and how representative they are of the population as a whole. An initial assessment can be made using any group of potential consumers available, e.g. company employees. The group are asked to taste the new product and answer a questionnaire to express their opinion. A `standard' of existing products or competitor products can also be included to provide comparisons. A more detailed opinion can be achieved by targeting the intended market group, e.g. teenagers, 20±30-year-old women, etc. Market research agencies will design questionnaires and run assessment centres of target groups in various parts of the country. Questionnaires can cover aspects such as price and potential drinking occasions in addition to merely degree of like or dislike. Commercial market research agencies maintain access to groups, such as schools, youth clubs, housewives, etc., that can be called upon to proffer an opinion on new products. Targeting the correct sector of consumers and obtaining a realistic assessment of purchasing intention are important, but the responses of interviewees are not
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Soft drink and fruit juice problems solved
always in line with their actions under real circumstances. Ideally a small test market should be used to assess consumer reaction to a new product. Drinks can be allocated to a small local area and the consumer response evaluated. This provides the most reliable prediction of potential sales. 1.7.2 Can I outsource market research and, if so, to whom? Companies often outsource their market research activities to agencies that specialise in the field. These agencies maintain facilities across the country with the capability of sampling the number and demographic profile required and analysing the results. Only the very largest food and drinks companies can maintain this type of facility in-house. Further information and details of market research companies can be obtained from the Market Research Society (MRS) on their website www.mrs.org.uk. 1.7.3 How long should a new product be given to find its place in the market? The time taken for a product to establish itself in the market will depend upon many factors, including the type of product, the market sector into which it is being launched, and the amount of promotion provided. Sales departments like to see a new product achieve significant sales in its first year and to increase in the second and subsequent years. Major companies are able to invest large sums of money into a launch fanfare and advertising campaign in order to establish trial purchases. Small companies depend more on a gradual product roll-out and on establishing sales by steady growth. There is an old sales maxim that the faster sales rise the faster they fall, and there is some truth in this. Occasionally a new product catches the public imagination and sales exceed forecasts by an order of magnitude. Such `fads' usually subside equally rapidly as the market moves on to the next fad, but if sales grow steadily year on year the product will probably maintain a longer lifespan, building a core of regular consumers. Some products may perform extremely well in their first year due to a combination of novelty and marketing hype, but sales collapse the following year when the high-profile marketing support is removed. Products launched into the traditional licensed trade are frequently slow to build sales volume. This is because many drinkers in bars and pubs are less prone to try something new, preferring to stick to their usual drink, and products are kept behind the bar and are therefore less obvious to the customer. 1.7.4 How can I predict likely sales volumes? For a completely new product, predicting sales volumes is very difficult. Extensive market research conducted in the target market can provide information on the public's propensity to purchase the product at a given price. Such predictions are notoriously unreliable, however. Experienced sales personnel will have a
Product development of new soft drinks and fruit juices
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`feel' for likely sales volumes knowing the outlets, sales of current products and data from the consumer research. If the product is merely an extension to an existing range then the estimate is likely to be more accurate than for a completely novel product. Market research on test consumers' propensity to purchase, and research on price elasticity compared to competitor products, will help refine the prediction. The most accurate means of predicting likely sales volumes is to hold a test market in selected outlets, perhaps in different parts of the country. This can be extended to a small region and rolled out nationally. The test market does have the disadvantage that it indicates your product and plans to your competitors.
2 Ingredients in soft drinks and fruit juices Abstract: This chapter lists and answers key questions relating to ingredients used in soft drinks and fruit juices. It covers water, fruit components, carbohydrate sweeteners, intense sweeteners, flavourings, colourings and preservatives as well as ingredients for carbonation. Key words: soft drinks, fruit juices, ingredients, sweeteners, flavourings, colourings, preservatives.
2.1
Water as an ingredient
2.1.1 How much does water quality affect soft drinks? Water is the principal component in all soft drinks and reconstituted fruit juices and it can have a fundamental effect on the quality of the end product. If water used in the manufacturing process is supplied by a reputable utility supplier and is fit for drinking as such, its quality is likely to be acceptable for use in beverage manufacture with minimal treatment solely for the purpose of removing chlorine and any other flavour taints. However, many soft drink plants have their own private water supply and the water from such sources may or may not be of suitable quality. In the United Kingdom, water from a private supply that is used in a food manufacturing process is subject to the constraints of the Private Water Supplies Regulations (those for Scotland were published in 2006; those for England will be published in 2009) to ensure that certain key quality criteria are met. Further information about appropriate treatments and quality specifications appear in subsequent answers. The key factors that particularly need to be considered in relation to water to be used in soft drinks, assuming the water meets the quality requirements of the EU Water Directive for Drinking Water (98/83/EC), are as follows.
Ingredients in soft drinks and fruit juices
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· Chlorine should always be removed as it sometimes reacts with other flavour or fruit constituents in a way that allows the development of a `disinfectant' taste due to the formation of complex chlorophenols. · Hardness The level of water hardness will affect the acidity of a soft drink or fruit juice and, in extreme situations, can create a buffering effect that will alter the pH of the product and possibly its microbiological stability and taste. · Nitrate levels may be an important factor if the product is to be provided for babies or young children. · Calcium levels, particularly in products containing high percentages of fruit components, may be important depending on the quality of the fruit constituent. If the pectin content of the fruit material has been degraded (see below), free calcium can react to form stable gels that create an unsightly and unpleasant end product. · Iron and other metal ions can catalyse reactions that can create flavour and colour defects, particularly in products that are fortified with vitamins or other miscellaneous additives. · Sunlight The use of water that has been subjected to prolonged exposure to sunlight (e.g. in an open reservoir in the summer) when algal blooms have occurred can lead to the formation of white floc in the end product. Such flocs are created by polysaccharides that occur as algal breakdown products. 2.1.2 Should water treatment be installed in a soft drink or fruit juice processing plant? As a general guideline, water used in products should at least meet the quality standards of the EU Drinking Water Directive. Even then it will almost always be desirable to subject all process water to filtration or percolation through active carbon to remove chlorine and any other flavour taints. Other treatments may be considered desirable if there are particular constituents in the water that need to be removed or reduced (e.g. calcium). When identical branded products are to be produced in more than one location or country, it is often the case that the brand owner will insist on water treatment to ensure product consistency wherever it is produced. In such situations the water quality required and the corresponding treatment needed will be specified by the brand owner. Where water supplies do not conform to the EU Drinking Water Directive standard, it will be necessary to evaluate the quality and decide on an appropriate treatment. The usual range of treatments, where employed, will often incorporate removal of unstable iron (e.g. by oxidation and flocculation), removal of sediments by sand filtration, softening by ion exchange, and sterilisation by addition of chlorine gas and its subsequent removal by filtration through active carbon. Immediately before use water is usually exposed to ultraviolet (UV) light.
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Soft drink and fruit juice problems solved
2.1.3 Is there an ideal specification for water to be used in soft drinks? It is evident from previous answers that water to be used for soft drinks or for reconstituting fruit juice concentrates must be fit for human consumption and preferably meet all the guide values of the EU Drinking Water Directive. However, within the permitted range of individual constituents the variation is still large. The ideal specification for a soft drink can probably be determined by reference to its microbiological quality, hardness, and freedom from toxic substances. Thus a water would, ideally, be free from all microbiological contaminants but especially coliforms as evidence of faecal contamination, Cryptosporidium and Giardia. It would also be free from toxic substances such as heavy metals, hydrocarbons, pesticides, herbicides, dioxins, etc. (`free from' in this context would usually mean not being detectable at an agreed limit). The water would also be low in content of metals such as iron, zinc and copper, low in calcium, sodium and potassium contents, and have a total solids content of less than 100 ppm. Freedom from dissolved oxygen is also desirable. 2.1.4 How frequently should water testing take place? Depending on the nature of the water source, it may be possible to avoid any expense of testing. If water is supplied by a utility that has a statutory obligation to maintain water quality, informal arrangements may sometimes be made for the utility to take regular water samples from the soft drinks plant as part of their network sampling programme. Water that is supplied as part of a private supply must be tested on a regular basis to meet the obligations set out in statute (the Private Water Supplies Regulations). Probably the most important test is to assess the microbiological quality, as the physico-chemical parameters are often reasonably stable. The testing parameters and frequency of testing required are set out in the above regulations. Testing of sources of `Natural Mineral Water' and `Spring Water' is a key part of the assessment and formal approval process, and testing of a wide range of parameters is an essential part of maintaining the reserved status. Irrespective of the testing required by regulations, individual manufacturers may wish to set in place their own testing programme as part of a normal quality assurance scheme. This may be a condition of maintaining a franchise for internationally branded products. 2.1.5 Can I use natural mineral water or spring water to make a soft drink or reconstituted fruit juice, and can I bring these waters in by tanker? The use of natural mineral water or spring water as an ingredient in soft drinks or reconstituted fruit juices is permitted. This can present a useful marketing opportunity, as the nature of the ingredient can be referred to in the list of ingredients (in the case of soft drinks). The status of a natural mineral water (as water) requires that it is `bottled at source' and thus precludes the use of a mobile tanker if the reserved description
Ingredients in soft drinks and fruit juices
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is to be maintained. There is no regulation preventing the use of a tanker to import natural mineral water to a plant but the reserved description may not then be used. Spring water may also be used as an ingredient in the manufacture of soft drinks. It should be borne in mind that although there may be a marketing advantage in using natural mineral water or spring water, the physico-chemical characteristics may not be ideal for the manufacture of soft drinks or the reconstitution of fruit juice concentrates. 2.1.6 Is a `flavoured' water a soft drink or a water? The legal description that is probably correct for a flavoured water is either `x flavour soft drink' or `x flavour low calorie soft drink'. The only permitted additive in water that allows the definition of water to be maintained is carbon dioxide. The addition of flavourings, sweeteners, colourings, citric acid or other permitted acids removes the product from what may legally be sold as water. In all situations where there is any doubt over the legal status or correct description of a product, appropriate legal advice should be sought and the product label sent for approval to the local authority trading standards department in the UK or to the competent authority in other countries.
2.2
Fruit components as ingredients
2.2.1 What types of fruit components are readily available and what are the differences between juices, comminutes, fruit pureÂes and fruit extracts? Fruit juices are obtained from most fruits by mechanical expression, although there are a wide variety of available processes to extract juice. The physical nature of the fruit becomes a major consideration and different techniques have to be applied to citrus, pome fruits (apples and pears), and fruits that contain pits (stones) such as mango. Fruit juices are invariably mobile liquids that contain a wide variety of constituents, although sugars and fruit acids predominate. Many fruit juices are available in both a clear and a cloudy form. A typical sweet fruit juice will contain between 8% and 15% dissolved solids. Most commercially available juices are produced both as direct juices (i.e. straight from the fruit, known commercially as `not from concentrate' (NFC) juices) as well as in the form of a concentrate that can be reconstituted to drinking strength. All juices need to be pasteurised to ensure a reasonable shelf-life, although the filling and packing operation can extend the life significantly. Only juices designated `freshly squeezed' tend to be unpasteurised; such juices must be kept cold and sold quickly. There is no clear distinction between fruit juices and pureÂes, as almost all juices contain more or less pulp on pressing. A fruit pureÂe is probably best described by its high level of pulp and other insoluble components and its
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Soft drink and fruit juice problems solved
viscous nature. Fruit pureÂes are often produced by simply crushing the whole fruit and removing gross particles such as seeds, large pieces of peel, etc. Fruit pureÂes are usually unconcentrated, although concentrated juices are sometimes added, and must be preserved to ensure physical and microbiological stability. Comminutes, or comminuted fruit, is a term reserved for citrus where parts of all the main components, flavedo (peel), albedo (pith), juice and peel oil, are combined into a pulpy mixture that is milled and pasteurised. Early examples were simple whole fruit comminutes, although these rapidly gave way to more refined products where the fruit is processed into its different components and recombined in proportions required by the user to deliver specific flavour and appearance characteristics in the finished product. Comminutes are used for the production of `whole fruit' drinks. (The term `whole fruit drink' was a reserved description in UK food legislation until repealed in 1995.) A further refinement of comminutes was to add concentrated juice rather than direct juice and thus produce a preparation concentrated up to five times. Comminutes deliver more colour, flavour and cloud than the corresponding juices. The term fruit extract, or fruit sugars (`fruit sugars' has a specific meaning within the legislation of some European countries ± see 2.3.5), is normally used to describe concentrated juices, particularly those from apples and grapes where some of the components have been removed to leave a clear and almost colourless syrup with a high concentration (65±70%) of sugars. Components such as coloured materials are removed, as are some of the acidic components. Such products were, when first commercially available, described as fruit juice concentrates to minimise EU sugar duties, and the term fruit extracts is now used to avoid misrepresentation. 2.2.2 What, if any, special processing is needed for packed fruit juices and products containing fruit ingredients? With few exceptions, packed fruit juices and products containing fruit ingredients at almost any level will need to be pasteurised in one way or another. The addition of fruit juice or other fruit ingredient makes the end product very vulnerable to microbial spoilage unless heat treated. Pasteurisation of the end product is essential, irrespective of any pre-treatment given to the fruit ingredient before its incorporation into the final product. The only exception that normally applies is to products such as `freshly squeezed' juices that have a very short shelf-life and are sold from a cold cabinet. The use of chemical preservative(s) in a soft drink containing fruit components (they are not permitted in pure fruit juices) does not normally remove the need for pasteurisation of the end product. 2.2.3 How do I calculate the fruit content of a product when using a concentrated fruit preparation? Most fruit preparations are primarily described, in terms of their concentration, either in ëBrix or in grams per litre of citric acid for very acidic juices such as
Ingredients in soft drinks and fruit juices
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lemon or lime. The term ëBrix refers strictly to an optical property of solutions of pure sucrose in water (e.g. 50ëBrix is 50% w/w sucrose in water) but it is a useful way of referring to most sweet fruit juices. It may be necessary to adjust the ëBrix value to account for acidity to obtain a more accurate measurement. In order to calculate the value of fruit content in a beverage (be it pure fruit juice to be made by reconstitution from a concentrate or a product containing a percentage of fruit), it is necessary to have access to standard values for direct juice. These are available from a number of sources such as the Codex Alimentarius or the European Fruit Juice Association (AIJN). The problem is best described by reference to a specific example. A manufacturer wishes to produce the maximum amount of a reconstituted orange juice to the AIJN standard of 11.2ëBrix from 1000 kg of orange juice concentrate at 66ëBrix. Because ëBrix is a property related strictly to mass, any conversion to volume will require access to tables relating ëBrix to relative density and solids content per litre. Thus, 1000 kg at 66ëBrix will deliver a theoretical quantity of juice at 11.2ëBrix of 1000 66/11.2 5892.8 kg. As the relative density of 11.2ëBrix juice is 1.042, the volume expected will be 5892.8/1.042 5655.3 litres. 2.2.4 What factors do I need to consider in the specification for fruit ingredients? There are a wide range of parameters that should be considered when specifying fruit ingredients, some relating to commercial interest and some to technical. The initial consideration may be that of value for money when the solids content, acidity and ratio of the juice or concentrate are important. Assuming these are considered to be satisfactory, attention should then be given to the appearance and taste characteristics of the juice. Depending on what the juice is required for, the colour and cloud stability may be more or less important, although any colour deterioration may be the first indication that the juice has been stored for a considerable time or in inappropriate conditions. Lack of cloud stability may be indicative of either poor processing or current enzyme activity. The taste of the juice should be characteristic and free from stale, cooked or off flavours. Assuming the above characteristics are all acceptable, the juice or fruit component should be free from any microbiological activity or enzyme activity. However, this matter needs to be considered in relation to the fruit component. If the juice is direct juice that has been very recently produced from the fruit and is to be sold as such, both microbiological and enzymic activity would be properly present and controlled by reduced temperature during a very short shelf-life. The presence of microbial and/or enzymic activity in a processed juice would be likely to render that product unacceptable. If all the previously mentioned characteristics are found to be acceptable, consideration must then be given to the authenticity of the juice. This issue is almost exclusively of consideration for pure juices to be sold as such. Various
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Soft drink and fruit juice problems solved
methods and laboratories are available for assessing juice authenticity, and expert advice to decide the most appropriate method for assessing this quality may be needed. 2.2.5 What kind of problems can arise from the use of fruit in a soft drink? The inclusion of fruit in a product, usually in the form of fruit juice, will often make the product more vulnerable to the effects of spoilage organisms such as yeasts and moulds and in consequence normally makes the use of pasteurisation essential. Where the juice is very acidic (e.g. lemon or lime juice) pasteurisation can sometimes be eliminated. The use of fruit will often contribute cloud or sediment to the product and care may be needed to avoid visual defects. For example, where the fruit component has a high pulp content, entrainment of air during mixing can cause the pulp content to form an unsightly plug in the neck of the container into which it is packed. Poorly processed fruit where the pectin content has been degraded may also leave the product vulnerable to the formation of a gel where the product water used has a high calcium content. 2.2.6 Are all exotic fruits permitted in beverages and how can I establish which are allowed? As a general guideline, all exotic fruits that are in use throughout at least the European Union are permitted as ingredients either as components in a soft drink or as a fruit juice in their own right. However, many exotic juices are for one reason or another unsuitable for use as a pure product, either because they have a particular characteristic, such as acidity, that makes them unpalatable or because their flavour is so strong that they are unacceptable to consumers except as part of a tropical fruit blend. As an example, the juice of passion fruit is often very acidic and is usually unacceptable to consumers unless diluted and sweetened. Many companies are constantly seeking new flavours and taste sensations for their beverages, so the search for new and unusual flavours is more or less continuous. Apart from the issue of taste acceptability, the commercial availability of some single exotic juices is often at best variable, and unless there is a steady take-up, sources can disappear very quickly. The cost implications can also be great, as quantities tend to be relatively small with correspondingly high production costs and shipping problems. If the source is in a remote and less developed country, the suitability of containers can also become an issue. If there is doubt over the acceptability of individual juices, it may be prudent to consult the Novel Foods Regulations (EU, 1997) which provides a definition: `Novel foods or novel food ingredients are foods or food ingredients which have not previously been used for human consumption to a significant degree within the (European) Community and which fall into the following categories:
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(a) foods and food ingredients containing or consisting of genetically modified organisms within the meaning of Directive 90/220/EEC; (b) foods and food ingredients produced from, but not containing, genetically modified organisms; (c) foods and food ingredients with a new or intentionally modified primary molecular structure; (d) foods and food ingredients consisting of or isolated from microorganisms, fungi or algae; (e) foods and food ingredients consisting of or isolated from plants and food ingredients isolated from animals, except for foods and food ingredients obtained by traditional propagating or breeding practices and having a history of safe food use; (f) foods and food ingredients to which has been applied a production process not currently used, where that process gives rise to significant changes in the composition or structure of the foods or food ingredients which affect their nutritional value, metabolism or level of undesirable substances.' Foods or ingredients that do not comply require assessment, a process that is likely to be both expensive and time consuming. There is likely to be a worthwhile commercial argument for such an assessment only if the proposed exotic juice has unusual qualities. In practice, juice packers and beverage manufacturers would be best advised to rely on the supply source for compliance with UK/EU regulations. 2.2.7 Can a product be labelled `sugar free' if only fruit components are added? It is important to distinguish between the descriptions `sugar free' and `no added sugar'. Virtually all fruit juices contain a blend of naturally occurring sugars, most commonly, fructose, glucose and sucrose. Typical ranges or levels of these sugars for common juices are as follows: Juice Apple Grape Grapefruit Orange
Glucose (g/kg)
Fructose (g/kg)
Sucrose (g/kg)
18±35 ca. 79 18±50 ca. 22
55±80 ca. 81 19±50 ca. 24
5±30 Not typically present ca. 35 ca. 45
Sucrose rapidly inverts to fructose and glucose in the acidic conditions of fruit juices. The nutrition labelling of fruit juice drinks is legislated by the Nutrition & Health Claims Regulations 2006 (1924/2006) and terminology is defined. `Sugar free' may only be used for drinks containing <0.5 g sugar per 100 ml. For
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Soft drink and fruit juice problems solved
fruit juice drinks which contain only sugars derived from fruit juices the term `No added sugar' may be used but in conjunction with the term `Contains naturally occurring sugars'. Concentrated grape or apple juices which have been de-aromatised and deionised are sometimes used to sweeten drinks. These should be declared as sweetener not as fruit juices (see 2.3.5). 2.2.8 How can I be sure of the authenticity of fruit materials? The authenticity of fruit materials is an issue that is potentially always present. It is more likely to become a serious problem when fruit juices and related items are in short supply or are very expensive. Fruit juice adulteration can take a number of different forms. At its simplest, juices may be diluted by the addition of small amounts of water, but it is more likely that additions to juices will take the form of added carbohydrates or other components such as the addition of malic acid to apple juice or the excessive addition of pulpwash to citrus products. Historically the addition of relatively low-cost carbohydrates, such as those from cane or beet sugar or from hydrolysed corn starch, has been the most likely form of adulteration of fruit juices, particularly orange. Since juice adulteration is invariably linked to the generation of more profit for the supplier, potential adulterants are almost always of lower cost than the related components that occur naturally in the juice concerned and are thus relatively limited in scope. Over the past two decades much effort has been expended in the development of analytical methods aimed at identifying adulterated juices and thus providing confidence of authenticity to the purchaser. A variety of techniques are now available commercially, including the use of stable isotope analysis to identify the type of carbohydrates present or the detection of small quantities of oligosaccharides that characterise particular carbohydrate sources. Synthetic malic acid can also be readily detected as can the excessive use of pulpwash to citrus juices. Other techniques include the use of multivariate analysis to compare respective quantities of minor components. A key requirement of any authentication programme is the setting up of a database that covers the widest possible range of supply sources. During the early years of regular authentication testing many false-positive results were produced as a result of a database that was too narrow. National and regional testing schemes are now available to provide support to juice purchasers, but the highest level of confidence of juice authenticity is likely to be provided by a combination of supplier audit and a statistically significant testing programme.
Ingredients in soft drinks and fruit juices
2.3
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Carbohydrate sweeteners
2.3.1 What carbohydrate sweeteners are available for use in soft drinks? Sucrose (commonly referred to as `sugar') is a disaccharide consisting of the two monosaccharides glucose and fructose. These three carbohydrates provide the natural sweetness in fruit juices and soft drinks, singly or in combination. Sugar The standard carbohydrate used in soft drinks is sugar (sucrose) derived from either sugar cane or sugar beet. This is commercially available as either granulated solid or as a concentrated syrup, usually 67ëBrix. In the EU the production of bulk sugars is rigidly controlled by the Common Agricultural Policy (CAP). At the time of writing the CAP is in the process of being reformed. Sugar is purchased as `tonnes dry weight'. This allows for minor variations in the Brix value of sugar syrups. Granulated sugar is generally cheaper (per tonne dry weight) than sugar syrup but requires specialised handling and dissolution facilities (see 2.3.6). Invert sugar Sucrose hydrolyses slowly in acidic solution to its two constituent monosaccharides, glucose and fructose, a process known as inversion. Therefore soft drinks manufactured using pure sucrose slowly invert to contain a mixture of sucrose, glucose and fructose. A 1:1 mixture of glucose and fructose is known as invert sugar but is rarely used in soft drinks. Glucose syrup Starch derived from wheat or maize can be processed to form glucose syrup. Glucose is about 20% less sweet than sucrose and is only used to manufacture speciality energy or sports drinks, where it provides greater energy per unit of sweetness and rapid uptake of energy by the body. High fructose glucose syrup (HFGS) Glucose syrup can be converted enzymically to HFGS, sometimes called high fructose corn syrup (HFCS). Due to restrictions imposed by the Common Agricultural Policy (CAP), the standard HFGS sold in the EU contains a maximum of 42% fructose, but in the USA further purification is employed to raise the fructose content to 55%. HFGS is a direct replacement for sugar which it has now almost completely replaced in soft drinks manufacturing in the USA. The manufacture of HFGS in the EU is severely restricted under the CAP by a quota system. The tonnage available for soft drinks manufacturers is therefore limited. This is to protect sugar beet growers. In the UK HFGS represents only about 2% of the total sugars used by the food and drink industries.
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Soft drink and fruit juice problems solved
Fructose syrup A syrup containing approximately 85% fructose and 15% glucose is derived commercially from chicory grown in northern France, the Netherlands and Belgium. This syrup is used in soft drinks manufacture but as with HFGS its availability is severely restricted by the CAP. Legislation The specifications and labelling requirements of bulk carbohydrate sweeteners are controlled by the EU Directive 2001/111/EC. This is transcribed into UK legislation as the Specified Sugar Products (England) Regulations 2003 SI No.1563 and parallel regulations for Scotland, Wales and Northern Ireland. Specialist carbohydrates Three speciality carbohydrates have been permitted in the EU since 2001: · Trehalose, approved September 2001. Consists of two glucose units with the same energy value as sugar but only 40% of the sweetness. · Iso maltulose, approved April 2005. An isomer of sucrose with the same energy value as sucrose but less than half the sweetness. · D-tagatose, approved December 2005. Chemically similar to fructose but with similar sweetness to sugar. It is only slowly and partially metabolised and therefore has a low energy value. These three sugars are only for use in speciality sports or dietary drinks. It is important to note that polyols, e.g. sorbitol or xylitol, are not permitted for use in soft drinks in the EU. They were used in diabetic products prior to the introduction of good quality intense sweeteners in the mid-1980s. 2.3.2 How do other sweeteners compare with sucrose? Sucrose is always considered to be the standard sweetener to which all others are compared. Relative sweetness The relative sweetness of different sweeteners varies depending upon the level of usage and the product in which they are being used. However, glucose is about 20% less sweet than sucrose, and fructose is about 25% more sweet. Fructose Fructose is generally considered to give a superior flavour in juice drinks. It also provides 25% fewer calories (for an equivalent sweetness) than sugar and has a low glycaemic index, which may be important in some products. Fructose metabolism is not insulin dependent; it is metabolised more slowly in the liver. Note that excessive consumption of fructose can cause diarrhoea.
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Glucose As glucose is 20% less sweet than sucrose, it is not generally used as a sweetener in soft drinks except for specific purposes, e.g. for energy in sports drinks. Glucose is absorbed directly from the stomach into the blood where it provides an immediate source of energy. All other carbohydrates must be converted by the body into glucose in order to provide energy. HFGS The syrup containing 55% fructose as used in the USA is a good straight replacement for sugar. The 42% fructose syrup used in the EU, although not quite such a good replacement, is adequate. HFGS is slightly cheaper than sugar but its availability is limited in the EU by the CAP. Note that changing the sweetener system from, say, sucrose to 42% HFGS requires changes to the composition of other ingredients and flavours to minimise changes to the overall product character. 2.3.3 Do different sweeteners affect product stability? The use of different bulk sweeteners does not generally impact significantly upon the stability of finished drinks. However, the grade (purity) of the bulk sweetener can have a marked effect, particularly on products which are susceptible to oxidation, e.g. citrus drinks. Use of a premium-grade sweetener can significantly extend shelf-life (see 2.3.7). Lower-grade bulk sweeteners are less highly refined and contain higher levels of contaminants such as metal ions which can promote flavour breakdown. In particular, the use of HFGS having a high mineral content can reduce the microbiological stability of drinks, which was a problem with some HFGS when it was first introduced. Most supplies are now deionised and this has ceased to be a problem. A high concentration of sugars provides a degree of protection from spoilage organisms, growth of which is inhibited at higher Brix levels. Carbohydrate syrups at the normal commercial strengths of 67±74ëBrix are microbiologically stable due to the high concentration of sugars and resultant low water activity. 2.3.4 How do different sweeteners affect production and process control? Process control during the blending and bottling operation is usually monitored by Brix measurement. Brix can be accurately and rapidly measured by means of a refractometer, and this is usually the standard means of controlling the `throw' of the syrup, i.e. the ratio of syrup to water during bottling. The viscosity of the syrup will vary slightly, depending upon the type of bulk carbohydrate used, and the blending of syrup and water will therefore require recalibrating. Note that production of sugar-free or low-calorie drinks cannot be monitored by means of refractometric Brix and a suitable alternative must be used. It is usual to monitor the production of low-calorie drinks by means of the total acidity of the final product, as this can be determined quickly and relatively accurately.
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Soft drink and fruit juice problems solved
Inversion of sucrose (hydrolysis to fructose and glucose) will cause the Brix of bottling syrup to slowly increase by up to 5% on prolonged standing, especially if the syrup is warm. This does not happen if HFGS is used, because inversion cannot occur since no sucrose is present. Different bulk carbohydrates require different specialised handling facilities in production (see 2.3.6). 2.3.5 What are `fruit extracts' and how should they be labelled? Fruit juices naturally contain sugars. For example, grape juice typically contains around 15% sugars, predominantly fructose. The ratio of fructose, glucose and sucrose in fruit juices varies depending upon the type of fruit. Fruit juices can be subjected to varying degrees of processing, such as carbon filtration and deionisation, as required, to remove the flavour, colour, acidity, etc., which will result in a syrup high in sugars, mostly fructose. This `fruit extract' can be used to provide sweetness to fruit drinks in place of sucrose (sugar). It does not comply with the legal definition of fruit juice as laid down in the Fruit Juice Directive 2001/112/EC and cannot therefore be included in the declared fruit or fruit juice content. Fruit extract could also be declared in the ingredients list as `fruit sugars'. For marketing purposes some manufacturers do not wish to have `sugar' in their ingredients lists and `fruit extracts' is seen as a more natural, alternative form of sweetener. Also in German the term fruit sugar (Frucht Zucker) is used specifically to mean fructose and therefore cannot be used to describe this extract. 2.3.6 Are special technical or process requirements needed to enable the handling of bulk carbohydrates in dry or syrup form? Very specific processing/handling equipment is required for the handling of various bulk carbohydrates and no attempt must be made to handle them without the correct approved equipment being in place. Granulated sugar does not flow readily and if left in high humidity has a tendency to `cake' into a solid mass inside the silos, hence necessitating specialised storage facilities. Sugar dust dispersed in the atmosphere is highly explosive, necessitating the use of spark-proof electrical equipment and blastproof storage to deflect the force of any potential explosion upwards to minimise damage. Sugar dissolves only very slowly in cold water and specialist dissolution equipment is required for the manufacture of sugar syrup. Typically this involves the homogenisation of sugar into a continuous stream of water by means of a high-shear mixer. The fine particles of sugar suspended in water are then passed through a heat exchanger to produce rapid dissolution. The system can be automated to produce a continuous flow of defined Brix syrup. Alternatively, sugar can be purchased already dissolved, usually as a 67ëBrix syrup delivered in dedicated bulk tankers. Though usually slightly more
Ingredients in soft drinks and fruit juices
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expensive (per tonne dry weight) than granulated sugar, this removes the capital and operating costs of dissolution equipment. In terms of storage, concentrated sugar syrups are fairly resistant to microbiological spoilage due to their low water availability. However, they are prone to spoilage on the top surface because syrups are stored warm and this can cause condensation of water on the inner surface of the tank roof. The resulting film of water on the surface of the syrup is very susceptible to spoilage. It is usual to employ UV lights in the headspace above the syrup and to sterilefilter air entering the top of the tank as sugar is pumped out. Storage tanks must be sterilised regularly, say monthly. HFGS and glucose syrups usually have a solids content above 70ëBrix and must be stored warm. If these syrups are allowed to stand in cold conditions for any length of time, crystallisation will occur and the syrup will completely solidify in the tanks and pipework. It is essential to use insulated heated tanks and to heat any pipework. 2.3.7 What typical specifications should I apply to carbohydrates? Bulk carbohydrates are normally purchased on a `dry weight' basis. The dry weight content of syrup may vary slightly between batches and suppliers and is calculated from the weight of syrup delivered and its Brix. Sugar syrup is usually delivered at about 67ëBrix and HFGS at about 73ëBrix. The quality of carbohydrates is generally related to their colour. The lower the colour the lower the level of contaminants and the higher the quality (purity). A low ash content is important as the presence of minerals (metal ions) can impact adversely on the stability of finished drinks, both organoleptic and microbiological. The microbiological integrity of the syrup is also important, particularly if it is to be used in drinks that will not be pasteurised. Syrup should be delivered in dedicated tankers. If this is not possible then only tankers used for transportation of food must be used and certificates of cleaning and sterility must be obtained. It is important that the tanker, including all seals and valves, be thoroughly cleaned. Standard methods for the specification of sugar are published by the International Commission for Uniform Methods of Sugar Analysis (ICUMSA). The ICUMSA manual, containing 108 approved analytical methods, was revised in 2007.
2.4
Intense sweeteners
2.4.1 How do I select the right intense sweetener for my product? The key parameters to be considered when selecting a sweetener (or blend of sweeteners) are product taste, cost and shelf-life. Also of prime importance is to ensure that your intended intense sweetener is permitted in your intended market, as legislation on intense sweeteners varies considerably between
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Soft drink and fruit juice problems solved
countries (though not within the EU). Only six sweeteners are currently permitted to be used in soft drinks by the EU Sweeteners Directive (94/35/EC as amended). Test the sweeteners in your product to acquire the desired taste profile for your target market. Although an approximate usage rate for the sweetener(s) can be calculated, it is essential to make up and taste batches of the new drink in order to finalise the exact level(s). This is due to the interaction of the various components of the formulation in the mouth to produce the overall taste character. The most commonly used intense sweeteners are aspartame, acesulfame K, sucralose and saccharin. Cyclamate is not permitted in the USA and only at a very low level (250 mg/L) in the EU. Only aspartame and sucralose are permitted to be used at sufficiently high levels as the sole sweetener in a drink. Other sweeteners must be used in blends. The effective cost of sweeteners varies considerably. If low cost is an important factor, saccharin can be used as it is by far the cheapest sweetener. Aspartame slowly breaks down in low pH drinks and should not be used if a long shelf-life is important and/or if drinks are likely to be stored at elevated temperatures (e.g. in the tropics). In addition to legal differences there are also traditional differences between markets which should be taken into consideration. For example, saccharin has long been used in the UK soft drinks market but to a much lesser extent in mainland Europe. Likewise, cyclamate has been widely used in much of mainland Europe but is not used at all in the UK, due mainly to consumer resistance because it was formerly prohibited. The final sweetener of the six permitted in the EU is neohesperidin dihydrochalcone (NHDC). This suffers from the disadvantage that at levels approaching its maximum usage rate it has a pronounced flavour in addition to sweetness. It is therefore little used as a sweetener but at low levels (ca. 5 mg/L) it can be a useful flavour enhancer for juice drinks. Sweeteners permitted in the EU and maximum permitted usage rates are as follows: Sweetener Acesulfame K Aspartame Cyclamate NHDC Saccharin Sucralose
Maximum permitted usage 350 mg/L 600 mg/L 250 mg/L 30 mg/L 80 mg/L 300 mg/L
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2.4.2 Do different intense sweeteners have different taste profiles? The flavour profiles of these sweeteners are significantly different. In particular, they have very different relative sweetness values. The relative sweetness value of a sweetener is its sweetness compared to sucrose, which is given the nominal value 1. Approximate sweetness values are as follows: Sweetener Acesulfame K Aspartame Cyclamate NHDC Saccharin (as imide) Sucralose
Relative sweetness (approx.) 250 250 33 1500 550 550
Note that saccharin is frequently used as sodium saccharin dihydrate, which is more soluble but less sweet (ca. 450). Amounts of saccharin permitted and used are quoted as imide. Note also that the relative sweetness values quoted for each sweetener are only approximate. The actual value will depend upon the usage rate and the product in which it is being used. Additionally, intense sweeteners have different flavour profiles. Sucralose, cyclamate and aspartame are generally considered to have the closest individual sweetness profiles to sucrose. Saccharin suffers from a lingering bitter aftertaste, which acesulfame K also exhibits but to a very much lesser degree. Cyclamate is only permitted in drinks at a low level in the EU but it exhibits an excellent sweetness profile and blends well with saccharin. NHDC exhibits a very intense sweetness but it also imparts significant flavour at levels approaching its maximum permitted level of 30 mg/L. However, at levels of just a few mg/L it exhibits useful sweetness and flavourenhancing properties. 2.4.3 What kind of stability can I expect from intense sweeteners? Most intense sweeteners are very stable, demonstrating no significant reduction over a typical 12-month shelf-life. The exception is aspartame, which breaks down slowly in acid solution with a resulting loss of sweetness. This breakdown is accelerated by high temperatures and low pH. In order to minimise breakdown, the pH of a drink can be buffered to a slightly higher level with an acidity regulator, for example sodium citrate, in order to extend the shelf-life with minimal flavour impact. Manufacturers also typically use an `overage' of aspartame in the initial product to allow for an average loss prior to consumption. If a manufacturer knows the average age of the drink at consumption the initial overage can be fixed to optimise the sweetness at time of consumption. The drink will be a little
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Soft drink and fruit juice problems solved
too sweet when fresh and not quite sweet enough towards the end of its shelflife. Shelf-life can also be extended by blending with another sweetener. The synergy produced by blending also aids shelf-life. For example, the maximum synergy between aspartame and acesulfame K occurs at a 50:50 usage rate. Therefore in a blend containing 60% aspartame and 40% acesulfame K, as the aspartame breaks down the synergy between the two sweeteners will increase, tending to minimise the apparent sweetness reduction. Even using the techniques mentioned above, it is usual to limit the shelf-life of an aspartame-sweetened drink to approximately 6±9 months rather than 12 months for a sugar-sweetened drink. 2.4.4 Why does aspartame require special labelling? Drinks containing aspartame must indicate `a source of phenylalanine' on the label. This is a requirement of the EU Sweeteners Directive (94/35/EC). Aspartame is manufactured from two amino acids, aspartic acid and phenylalanine. People suffering from the hereditary condition phenylketonuria lack an essential enzyme and therefore cannot adequately metabolise phenylalanine. In the UK all babies are tested at birth for this condition, which is extremely harmful to small children, resulting in serious brain damage. Phenylalanine is found very widely in the diet, e.g. one small beefburger contains more phenylalanine than a dozen cans of diet soft drink sweetened with aspartame. However, since phenylalanine would not normally be expected to be present in a soft drink, the authorities require the use of advisory labelling in addition to aspartame being included in the ingredients list. 2.4.5 Are there any natural intense sweeteners? None of the six intense sweeteners permitted in the EU are `natural'. They are all manufactured synthetically. Even though sucralose is manufactured from sugar as the starting material, it cannot be called `natural'. There are, however, natural plant extracts that are sweet, for example: · Stevia, which contains the sweet extract stevioside, is used in the Far East and South America. Initial scientific evaluation has raised some questions about its safety and it is not currently permitted in the EU. However, considerable further studies are being undertaken and its use has been permitted by the FDA in the USA. It is anticipated that approval for its use in the EU may soon follow. · Thaumatin, which is a natural plant extract, is permitted in the EU for use as a flavour enhancer at low levels. It can enhance the apparent sweetness of soft drinks, though it is not a permitted sweetener.
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2.4.6 Why are intense sweeteners blended? Taste No intense sweetener tastes exactly like sucrose and a preferred sweetness character can sometimes be obtained by blending. The desired flavour profile can be obtained by using a blend of sweeteners. Aspartame/acesulfame and aspartame/saccharin are popular combinations. A blend of cyclamate:saccharin in the proportion 10:1 by weight was a good blend that was used frequently prior to the restrictions on cyclamate. Stability Aspartame is frequently blended with acesulfame K or saccharin to extend product shelf-life (see 2.4.3). If aspartame contributes only a part of the total sweetness then the loss of sweetness as it breaks down will be reduced proportionately. Synergy The sweetness of a blend of intense sweeteners is usually higher than would be expected from the sweetness of the two separate sweeteners. This apparent gain in sweetness is termed synergy. Under some circumstances this can be as high as 20%. Aspartame/acesulfame K and aspartame/saccharin exhibit marked synergy. An acesulfame K/saccharin blend does not exhibit synergy. The synergy and flavour character of a blend of sweeteners is usually optimal when blended in a ratio of 1:1 by sweetness. Cost The cost of a formulation may be of prime importance in certain markets and for certain products. Including a less expensive sweetener, e.g. saccharin, reduces the overall sweetener cost and can be an important factor. Use of sweeteners is very cost-effective compared to the use of bulk sugars, particularly in the EU, where the price of the latter is controlled by the CAP. Sweetening a drink using intense sweeteners can cost less than a quarter of the sugar cost. 2.4.7 Why has the use of cyclamate declined? A US study in the 1960s linked consumption of cyclamate to incidence of bladder cancer. This link was subsequently found to be incorrect. However, the use of cyclamate was prohibited in the USA and UK (from January 1970) but continued elsewhere. The EU Sweeteners Directive (94/35/EC) permitted the use of cyclamate in soft drinks to a maximum level of 400 mg/L and hence reestablished its use in the UK. Some manufacturers attempted to use cyclamate in soft drinks in the UK but met with extremely hostile media coverage. Following further evaluation, JECFA reduced the ADI for cyclamate from 22 mg/kg to 7 mg/kg bodyweight. Consequently the maximum EU usage rate in soft drinks was reduced to 250 mg/L. Since cyclamate has a low relative sweetness value (X33) this is equivalent to only
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Soft drink and fruit juice problems solved
0.8ëBrix of sugar. As a result of the adverse media coverage and very low permitted usage rate, UK manufacturers stopped using cyclamate. 2.4.8 Can I use sugar alcohols such as xylitol? No. The EU regulations do not permit the use of any sugar alcohols in soft drinks. Sugar alcohols, e.g. sorbitol, were previously used in the manufacture of soft drinks specifically for diabetics. However, their usage ceased following the introduction of intense sweeteners in the mid-1980s which produced much better drinks. The Sweeteners Directive (94/35/EC) lists a large range of confectionery and dessert products in which sugar alcohols may be used, but this list does not include soft drinks.
2.5
Flavourings
2.5.1 What types of flavourings are available and why are they used? The number of different flavourings available for soft drinks is almost infinite. Flavourings fall into three main categories ± natural, nature identical and artificial ± but in addition there are various sources of flavours for soft drinks that can be seen as part of the natural fruit components where used. Flavours are covered in the United Kingdom by regulations (EC, 2008) which define flavourings as preparations that contain at least one of the following components: · · · ·
Flavouring substances Flavouring preparations Process flavourings Smoke flavourings.
For soft drinks the most relevant categories are flavouring substances or flavouring preparations. Flavouring substances are chemical substances with flavouring properties and an established chemical structure. Flavouring preparations are products, other than flavouring substances, with flavouring properties that are obtained by physical, enzymatic or microbiological processes from appropriate vegetable or animal origin. Almost all flavourings for soft drinks use materials from one or both of these categories and the classification of the flavouring depends on the source of the key ingredients. Flavouring components that are derived from natural sources by physical, enzymatic or microbiological processes enable the flavouring to be described as natural. If they are derived by chemical synthesis but are identical to substances found in nature then the term `nature identical' is applied. Synthetic flavouring materials that do not have any natural counterpart require the flavouring to be called `artificial'. Flavourings are not permitted in pure fruit juices, although it is permissible (and in some interpretations obligatory) to add the volatile materials that are
Ingredients in soft drinks and fruit juices
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obtained during the process of producing fruit juice concentrates back to the reconstituted juice. Flavourings are, however, almost essential in many soft drinks where they mimic the described flavour of the product. Where fruit components are used they boost the characteristic flavour, and when no fruit is present they are required to deliver the required taste when superimposed on the sweetness and acidity of the formulation. Many characteristics of flavourings need to be considered when they are to be used in soft drinks, but solubility is of key importance. 2.5.2 How are flavourings best assessed in the development laboratory? The development of soft drinks usually requires consideration of the flavouring component as an essential part of the formulation process. Soft drink development is usually carried out for one or more of three main reasons: · To develop a new flavour or concept, including the production of an extension to an existing successful range of products · To match the product of a competitor · To effect a cost reduction. In all these scenarios the assessment of flavour submissions from potential suppliers is of essential importance. Ultimately the only assessment of a flavour submission that has to be considered is its performance in the final formulation. However, before that stage is reached other assessments are usually carried out. The process normally begins by preparing a product brief for the required flavour(s) to be sent to one or more flavour suppliers. The brief should include as much information as possible but particularly the fact that it is for a soft drink. Many flavour houses will then supply samples for consideration made up into a simple sugar/citric acid formulation, although some will provide a small quantity of the flavour as well to enable its characteristics outside the end product to be assessed. In the soft drink development laboratory the various submissions need to be evaluated side by side in an identical simple formulation such as 10% w/v sucrose in water with the addition of around 0.1±0.3% w/v citric acid anhydrous. The flavour sample(s) that are considered worthy of further evaluation will then be assessed in a more complex formulation that takes into account all the required characteristics of the end product. These will normally be sent for approval to the marketing department and, if considered satisfactory, are set up for storage trials. The process of finding the suitable flavour is rarely achieved on the initial submission, and frequently many rounds of submissions are necessary. 2.5.3 What kind of shelf-life do flavourings have? Flavourings for soft drinks usually contain a large number of chemicals from either natural or synthetic sources dissolved in permitted solvent(s). Some
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Soft drink and fruit juice problems solved
flavourings are presented in the form of an emulsion where insoluble or slightly soluble components such as essential oils are emulsified into a water base. These materials are normally used for delivering both cloud and flavour to a beverage formulation. Flavour chemicals are often very reactive and some are particularly susceptible to oxidation. The most unstable flavourings are usually those based on essential oils, particularly citrus oils, which are especially vulnerable to autooxidation. The terpene fractions of essential oils are the most reactive components and deterpenated oils are thus somewhat less vulnerable to rapid degradation than either whole oils or the terpene fractions. Fortunately for the beverage flavourist, the terpene fractions of essential oils tend to be the least soluble components and many beverage flavours are based on deterpenated oils (sometimes described as `folded oils'). However, the terpene fractions are often used in the manufacture of cloud emulsions. The manufacturers of flavourings are well aware of the stability of the individual products they manufacture and will normally indicate the shelf-life and storage conditions for their products. As a general guideline, flavourings should always be stored in full and unopened containers in a cool (5±10 ëC), dark environment. Storage of opened containers should be avoided where possible, and if storage does become necessary then it should be done for the shortest possible time. Most flavours will, in the correct conditions, have a shelf-life of at least 12 months, although citrus flavours are often limited to 6 months. Increasingly, flavour manufacturers will indicate a date of manufacture and either a best before or a retest date. In any event, users are well advised to check the acceptability of flavours that are close to the end of their recommended shelf-life. Care needs to be taken with flavour emulsions to ensure that both cloud stability and flavour are acceptable. 2.5.4 How do flavourings affect product stability? Flavourings perform a vital function in most soft drinks as they deliver much of the essential taste characteristic the manufacturer is seeking to deliver to the consumer. However, as will be seen from the previous response, flavourings are usually made up from complex mixtures of chemical substances, many of which are very reactive. As a direct consequence, there is always the potential for flavourings to impact on product stability. The beverage manufacturer will normally assess the stability of the final product in a series of shelf-life tests under different conditions and, assuming that the product is microbiologically stable in its container, it is usually the degradation of flavour that determines the end of what is considered to be acceptable shelf-life. Because of the reactivity of flavour components, the end product needs to be protected from the effects of oxygen and light. Protection of a beverage from oxygen is achieved firstly by taking steps to minimise the amount carried into the product or remaining in the headspace of the container. Some products,
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particularly fruit juices, can be subjected to vacuum deaeration during the processing stage, but this treatment is not usually applied to soft drinks where the main emphasis is on minimising the amount of oxygen in the headspace of the container after packing. For carbonated beverages this is not particularly difficult, as the presence of carbon dioxide will normally displace air in the container headspace. Care should be taken to ensure that the carbon dioxide is free from oxygen. For uncarbonated products, headspace flushing with nitrogen can be effective. Protection from light is best achieved by the use of coloured or opaque containers, although sleeving and wrap-round labelling can be a useful means of increasing light protection. The degradation effect that flavours can have on end products usually relates to the above effects of oxidation or effects of light, and there are characteristic off-flavours that are related to various flavours. For example, flavours used to produce lemonade often degrade to produce an almond-like taste. Light-struck off-tastes are also characteristic. If triacetin (glyceryl triacetate) is used as a solvent for the flavouring, off-tastes can arise as a result of its breakdown into acetic acid and glycerine. The presence of an off-taste in a product does not always arise from the flavour component, as the presence of micro-organisms can have this effect even when there are no other signs of spoilage. 2.5.5 How much interaction can I expect between flavourings and other ingredients? Interaction between flavourings and other components can usually be eliminated, or at least minimised, by ensuring that the flavour manufacturer is fully briefed at the outset of any flavour development work. Most flavours designed for soft drinks are, however, very stable in the presence of the normal ingredients of soft drinks, i.e. water, sugar or artificial sweeteners, citric acid and preservatives. Possible interaction with other components should be considered when drinks are likely to be fortified by the addition of vitamins and minerals or other miscellaneous additives. The most frequently used vitamin in soft drinks is vitamin C (ascorbic acid) and this substance, although very reactive, rarely causes any difficulties by interaction with flavourings. The presence of minerals such as iron, calcium or zinc can sometimes catalyse unusual and unwanted effects on flavours. There is no reliable means of predicting such interaction other than setting up appropriate storage trials, including accelerated testing by storage at elevated temperature, and evaluating results. The use of fruit components containing sulphur dioxide as a preservative should also be carefully monitored, as interactions between flavour and this preservative can in some circumstances result in some very unpleasant offtastes. Mention has also been made of possible interaction between flavour components and any chlorine in water used for manufacture (see 2.1.1).
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Soft drink and fruit juice problems solved
2.5.6 What different types of flavourings are available? Mention has already been made of the different categories of flavourings that give rise to the terms natural, nature identical and artificial (see 2.5.1). There are further classifications used within the industry that should also be considered. Natural flavourings that are obtained from materials of natural origin by physical, enzymatic or microbiological processes may be additionally described as FTNF (from the named fruit) or WONF (with other natural flavourings). In countries other than the United Kingdom and EU states, some flavours that are derived by chemical change of a natural ingredient may also be described as natural. Thus imports of flavours from sources other than EU countries need to be carefully evaluated if they are to be described as natural to meet UK/EU requirements. Other issues that are of particular importance for beverage manufacturers relate to aspects of labelling. If a manufacturer wishes to depict a fruit on the label of a product then there is a requirement within the current UK labelling regulations (HMSO, 1996) that unless `the flavour of the food to which the representation is applied is derived wholly or mainly from the food depicted' the pictorial representation shall not be applied. In practical terms this means that the flavouring used must be `wholly or mainly from the named fruit'. In a similar vein, the description `flavour' must not be preceded by the name of the food unless the flavour is again `wholly or mainly' derived from the food. Thus, an `orange flavour drink' may use any orange flavour, whereas an `orange flavoured drink' requires the use of an orange flavouring that comes wholly or mainly from oranges. The use of fruit (juice or comminute) in this situation would be taken into account. The other components used in flavourings, particularly solvents, are frequently not considered when assessing the status of the flavouring. 2.5.7 How do specific ingredients that add flavour, such as quinine and caffeine, have to be labelled? All ingredients of any food product, except those products for which ingredients listings are exempt, must declare a list of ingredients in descending order. It is thus a requirement that where caffeine and quinine are added as specific ingredients in a product they must be declared in the usual way. Quinine is only used normally in Indian tonic water where, to meet that specific reserved description, it must contain not less than 57 mg/L of quinine (calculated as quinine sulphate). It is theoretically possible to add quinine in the form of an extract of its natural source (cinchona), but for all practical considerations it has to be added as a pure substance to ensure compliance with labelling regulations by ensuring that the minimum level of quinine is maintained throughout the product life. There is now a specific labelling requirement (EU Commission Directive 2002/67/EC) that requires the presence of any quinine or caffeine added or used as a flavouring to be identified in the list of ingredients immediately following `flavouring(s)'.
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To provide consumers with additional information, it is also now a labelling requirement that drinks intended for consumption without modification and containing caffeine from any source in excess of 150 mg/L must declare `High caffeine content' together with the amount expressed as mg/100 ml in the same field of vision as the name of the drink. In the case of dehydrated or concentrated drinks, that declaration is required if the level of 150 mg/L of caffeine is reached after the product is reconstituted. The additional labelling requirement is that the product is marked with the words `High caffeine content'. It is noteworthy that this requirement does not apply to any drink based on tea or coffee or tea extract where the name of the food includes the term `tea' or `coffee'. Other miscellaneous additives will normally be identified in the usual way in the list of ingredients. 2.5.8 Do I need approval for `novel' flavours? Flavour companies are constantly engaged in the development of new or `novel' flavours. The key issue is whether the flavour developed falls into the definition of a `novel food' within the meaning of the UK Novel Foods Regulations referred to in 2.2.6. Flavouring substances are exempt from the Novel Foods Regulations; they fall under the control of EC 1334 (2008). Because the composition of flavourings normally remains a closely guarded commercial secret, it will often be impossible for the user of a flavouring to determine whether these Novel Food Regulations apply to a particular flavour submission. As a general guideline most flavour companies will only use flavour ingredients that are available within their normal inventory of ingredients, but in order to be able to offer new and unusual flavours a completely new ingredient will sometimes be incorporated. Such new ingredients may well be in the form of a plant extract. The approach that will normally satisfy the user of a flavouring is a statement by the manufacturer of the flavouring of its conformity with the legislative requirements of the country or countries in which it is proposed to sell the end product containing the new or novel flavouring.
2.6
Colourings
2.6.1 What factors are to be considered in selecting natural or artificial colourings? (see also 2.6.6) The primary consideration in any decision regarding the use of colourings of any origin is whether it is necessary to add colour of any kind to a product. This decision will be driven by the consumer perception of the expectation of a product's appearance. The use of artificial colours in beverage products has diminished significantly in recent years as, although a limited range of artificial colours remain permitted, they are regarded as unacceptable by many consumers. The list of colours permitted for use, quantum satis, in the 1995 UK Colours in Food Regulations within non-alcoholic flavoured drinks is as shown in the following table:
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Soft drink and fruit juice problems solved
E no.
Substance
E101
Riboflavin Riboflavin-50 -phosphate E140 Chlorophylls and chlorophyllin E141 Copper complexes of chlorophylls E150a Plain caramel E150b Caustic sulphite caramel E150c Ammonia caramel E150d Sulphite ammonia caramel E153 Vegetable carbon E160a Carotenes E160c Paprika extract, capsanthin, capsorubin E162 Beetroot red, betanin E163 Anthocyanim E170 Calcium carbonate E171 Titanium dioxide E172 Iron oxides and hydroxides The next table shows the permitted artificial colours and the maximum levels of use: E no.
Substance
E100 E102 E104 E110 E120 E122 E124 E129 E131 E132 E133 E142 E151 E155 E160e E160f E161b
Curcumin Tartrazine Quinoline yellow Sunset yellow FCF, orange yellow S Cochineal, carminic acid, carmines Azorubine, carmoisine Ponceau 4R, Cochineal Red A Allura Red AC Patent Blue V Indigotine, Indigo carmine Brilliant Blue FCF Green S Brilliant Black BN, Black PN Brown HT Beta-apo-80 -carotenal Ethyl ester of beta-apo-80 -carotenic acid Lutein
Maximum level of use (mg/kg or mg/L) 100 100 100 50 100 50 50 100 100 100 100 100 100 50 100 100 100
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The selection of colour will depend on a number of factors, including the preference for natural or artificial, the cost and availability, the actual colour or shade required, solubility and stability to acidic products, and overall stability in the product. Experienced formulators will usually work from a preferred shortlist but the final selection will depend on the performance of the colour in trial formulations. 2.6.2 How much added colour can I expect from fruit or other components? The amount of colour that can be expected from other ingredients of soft drinks varies considerably. The most obvious contributors of colour, apart from permitted colourings, are likely to be fruit juices, but components such as plant extracts and some flavourings may introduce some colour to the end product. Whether the amount of colour that is likely to be obtained from sources other than added colourings is sufficient for a specific end product is a highly subjective decision that is likely to be reached by the marketing department of a company in conjunction with research to assess consumer expectations. The amount of colour expected in a product may also depend on whether it is clear or cloudy. Some cloudy products, with the exception of ginger beers and lemonades, may have more colour than clear products. There are now many soft drinks available that are completely clear and colourless and use these qualities as a marketing platform. A product containing citrus juice is unlikely to meet consumer expectations for its appearance unless it has a substantial quantity (50% or more) of juice. Other products such as those containing berry juices, particularly blackcurrant juice, may have an acceptable appearance with a much lower juice content than 50%. Plant extracts are likely to be more or less brown in appearance. Flavours, on the other hand, particularly those containing concentrated fruit juices, may be able to contribute a range of colour. However, even natural flavourings are rarely used at more than 1% and the intensity of colour delivered in the end product is likely to be low. Some fruit compounds, especially those containing whole fruit (i.e. comminutes ± see 2.2.1), may deliver a significant level of colour because they can be manufactured to incorporate a higher level of the flavedo (coloured peel components) of citrus fruit. 2.6.3 Are there any ingredients that will give colour to a product but do not require a label declaration as such? Apart from those materials mentioned in 2.6.2 above, there are specialist products that have been developed from a range of plants. These may be used to give significant levels of stable colours to soft drinks and related products. The extracts can probably be expected to be declared as such with no reference being made in the list of ingredients to the presence of an added colouring. However,
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Soft drink and fruit juice problems solved
as with all labelling issues, any doubts should be referred to the competent authority (in the United Kingdom the local authority Trading Standards department) for a ruling decision. In the event of any significant dispute over labelling or related matters, only the courts are able to finally interpret the appropriate statute. The extracts used to donate colour to a product are likely to be from a variety of fruits and vegetables, including elderberries, red cabbage, aronia berries, hibiscus fruits and flowers, blackcurrants, orange and black carrots, pumpkins, grapes and tomatoes. This is not an exhaustive list but the above sources are known to deliver good colours which, in the appropriate product environment, are likely to be a useful source of colour. Not all the above sources are able to deliver colours that will be stable for soft drinks as there are particular requirements for solubility, stability to the acidic environment and possibly stability to light and interaction with other components. The specialist companies that manufacture such extracts can be expected to provide appropriate technical advice and formulation guidance, but it will always be essential to evaluate any proposed use of a fruit or vegetable extract in the final product formulation in relevant storage tests. 2.6.4 What are the main factors that affect the stability of colour in a product? Soft drinks are acidic products, usually with a pH between 2.7 and 3.7, and the first and critical issue is the stability of the colour in an aqueous medium of that pH. Most product formulators will be familiar with the colourants that are stable in acid media and if there is a problem with stability to acids it is usually quickly apparent. Most colour stability issues arise during the shelf-life of the soft drink and can be broadly divided into problems either from the effects of light and heat or from chemical interactions from oxygen or other constituents of the product itself. Light has probably the most damaging effect on soft drinks and products placed in clear bottles in a situation facing the sun will lose colour very quickly. A more representative test is to place a product in daylight where it is never exposed to direct sun. However, most manufacturers go to some length to protect products in trade. Packaging can be opaque, wrap-round labels can be used or a film can be applied to either the bottle or the secondary packaging. Assuming that a product has reasonable protection from light, another damaging component is likely to be oxygen. This can be either dissolved in the product or present in the headspace or both. Carbonated drinks tend to suffer less from the effects of oxygen, although the presence of oxygen in the headspace of a carbonated drink may affect the level of carbonation that may be achieved. Care should be taken to ensure that air is not drawn into the product during the mixing process, and the use of ascorbic acid as an oxygen scavenger is likely to be beneficial.
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Other components of a drink can, in some circumstances, affect the stability of its colour. For example, the preservative sulphur dioxide can act as a bleaching agent and ascorbic acid will, in some products, cause loss of colour. Unusual interactions affecting the colour of a product can sometimes occur when the product has added vitamins or minerals. The presence of some metal ions in water can also affect product colour. As with most other facets of soft drink formulation, products should be thoroughly shelf-tested before they are launched on the market. 2.6.5 There are several different types of caramels. What are the differences between them? · Caramel colour (Class I E150a), plain or spirit caramel is prepared by heat treatment of carbohydrates with or without the presence of alkalis or acids. These products are capable of withstanding high levels of alcohol and are therefore widely used in the colouring of whisky and liqueurs. · Caramel colour (Class II E150b), caustic sulphite caramel is prepared by the controlled heat treatment of carbohydrates with sulphite-containing compounds such as sulphurous acid and the sodium and potassium sulphites and bisulphites. Ammonium compounds are not suitable. These colours are again capable of withstanding high levels of alcohol but in the presence of vegetable extracts that contain tannins. They are therefore particularly suitable for colouring vermouths and brandies and are not widely used in the UK. · Caramel colour (Class III E150c), ammonia caramel is otherwise known as beer, bakers' or confectioners' caramel. These colourings are prepared by controlled heating of carbohydrate with ammonium compounds such as ammonium hydroxide, carbonate phosphate, etc. Sulphites are not used. These colourings are dispersible in water and can be used in low to moderate concentrations of alcohol as well as positively charged ions, high salt concentrations and some acidic conditions. They have reducing properties and are characterised by a strong charge. The main areas of use are in beer, baked goods, vinegars, syrups and pharmaceutical products. · Caramel colour (Class IV E150d), sulphite ammonia caramel is a group of caramels made by the controlled heating of carbohydrates in the presence of both sulphites and ammonium compounds. They are also known as `acid proof' or `soft drink' caramels and are dispersible in water and capable of withstanding high acid conditions. With a strong negative charge they are used almost exclusively in soft drinks and other non-alcoholic beverages. 2.6.6 Why are the media so critical of colourings? Food colourings permitted in the United Kingdom and Europe are amongst the most tested substances for adverse effects. Safety assessments are based on reviews of all available toxicological data, including observations on humans and animals. From the available data, a maximum level of an additive that has
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Soft drink and fruit juice problems solved
no demonstrable toxic effect is determined. This is called the `no-observedadverse-effect-level' (NOAEL) and is used to determine the `acceptable daily intake' (ADI) figure for each food colouring (or other additive). The ADI provides a large margin of safety and refers to the amount of a food colouring that can be taken daily in the diet, over a lifetime span without any negative effect on health. Set against such toxicological data is a large volume of mostly anecdotal information about claims of hyperactivity in children. It is likely that many parents and guardians can relate to the effects alleged to be caused by colourings. Almost all the alleged effects relate to specific synthetic colours and not those listed for use quantum sufficit (see 2.6.1). Claims of causing hyperactivity relate mainly to the following colours. These are now referred to as the `Southampton six' and may be subject to further legislative restrictions: · · · · · ·
E102 E110 E122 E124 E104 E129
Tartrazine Sunset Yellow Carmoisine Ponceau 4R Quinoline Yellow Allura Red.
Consumers are made aware of the presence of these colours in a product by the use of lists of ingredients. Despite these colours having a clear toxicological background and remaining permitted by national and European governments, they continue to be effectively blacklisted by various institutional and commercial organisations and there is now little effective use of the above permitted colours in the UK and Europe as consumers prefer to avoid products containing them. The colours are still widely used in many other parts of the world. Media concern arises from time to time, usually in relation to suggested public concern over a specific incident, and the issues of the alleged adverse effect of added food colours are again put before the public.
2.7
Preservatives
2.7.1 What factors should be considered in deciding whether to use any preservative? Preservatives are used in a wide variety of foods, including soft drinks, to ensure the safety of the food during storage. Preservatives are not permitted in pure fruit juices and either the packaging of these products has to give total protection (in the form of aseptic packaging) or the product should be kept chilled and sold quickly with or without pasteurisation. There is a limited range of permitted chemical preservatives for soft drinks; more details appear in 2.7.2. Almost all soft drinks are likely to support some growth of micro-organisms and even bottled water will frequently support the growth of bacteria that are
Ingredients in soft drinks and fruit juices
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usually harmless. Special care has to be taken to avoid the presence of harmful bacteria and other organisms, such as Cryptosporidium, in packaged waters. Soft drinks may be affected by bacteria, yeasts and moulds but because the pH of these products is almost always below 4.0 they are not normally considered likely to support the presence of harmful pathogens. Some freshly pressed (unpasteurised) fruit juices, particularly apple juice, have, however, been found to support the pathogen E. coli O157, and appropriate care should be taken by the producers and packers of such products. Yeasts and moulds are usually responsible for most spoilage in soft drinks. Yeasts frequently produce carbon dioxide gas as one product of their metabolism of sugar, and bottle bursting is frequently a consequence of yeast infections. Moulds, whilst not producing gas, do cause unsightly growth and affect the taste and appeal of a product. The ingredients that make soft drinks particularly vulnerable to the effects of bacteria, yeasts and moulds are substances that provide nutrition for the organisms. These include sugars and sources of nitrogen. Products sweetened by sugars are thus at risk, and especially vulnerable are those containing some fruit juice. The decision to incorporate chemical preservatives will thus depend on the ingredients to be used, the processing and type of packaging to be used and the nature of the end product. For example, products such as dilute-to-taste drinks are likely to be particularly vulnerable after opening as they are invariably stored in part-full containers in warm rooms. 2.7.2 How can the right preservatives be selected for a product? It will be apparent from the foregoing response that it is frequently desirable to incorporate chemical preservatives into soft drinks. This response assumes that it has been decided that preservatives are desirable for a particular product. The primary consideration is to evaluate the ingredients. The presence of fruit juice or whole fruit will make preservative use almost essential unless appropriate pasteurisation or aseptic packaging is contemplated. There are currently four permitted preservatives for use in the United Kingdom: sorbates, benzoates, sulphur dioxide (limited use) and dimethyl dicarbonate. Sorbic and benzoic acids are also effective preservatives but for practical reasons of solubility they are added as (usually) either their potassium or sodium salts to the soft drink mix before it is acidified. The maximum level of sorbic acid permitted in a soft drink for consumption is 300 mg/kg or mg/L as appropriate, although when used in combination with benzoic acid an upper limit of 250 mg/kg or mg/L applies. Benzoic acid is permitted at the level of consumption of 150 mg/kg or mg/L either singly or in admixture with sorbic acid. For concentrated drinks the amounts can be scaled up in accordance with the recommended dilution factor. These preservatives are the two most commonly used, although benzoic acid has been criticised anecdotally for possible allergenic effects and many commercial buyers will not allow this preservative in their products.
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Soft drink and fruit juice problems solved
The antimicrobial effect of a mixture of these preservatives is considered to be greater than the sum of their individual effects, although with high standards of production hygiene and good quality ingredients this factor is less important. The use of at least one of these two preservatives is recommended for any product, whether or not it is to be pasteurised, and they should always be incorporated into dilute-to-taste drinks unless special warnings are given for storage after opening. Sulphur dioxide was widely used in soft drinks up to about 1995 but is now limited to concentrated (i.e. dilute-to-taste products) at maxima of 350 mg/kg or mg/litre if barley is present or 250 mg/kg or mg/L if barley is absent. It may be introduced into other soft drinks containing fruit juice but only by carry-over from a fruit juice concentrate and then to a maximum of 20 mg/kg or mg/L. The particular value of sulphur dioxide was in non-carbonated ready-to-drink products where, because of its gaseous nature, it exerted a preservative effect in the product headspace. Such headspace protection can now be obtained from dimethyl dicarbonate which may be used at an ingoing amount of 250 mg/L with no residues detectable. The substance is very unpleasant to handle and must be directly injected into a stream of the product. It breaks down in the beverage to carbon dioxide and methanol and is effective in protecting headspace. Although not a preservative as such, carbon dioxide gas does exert a significant preservative effect in carbonated drinks. 2.7.3 Does the use of a preservative in a product mean that it does not need to be pasteurised? The preservatives that are permitted for use in a soft drink are mainly effective where the initial level of any microbial contamination is low. Thus it must not be assumed that the presence of preservative protects the product from microbial spoilage in all circumstances. As a general rule, unless a product is to be packed aseptically, or for marketing reasons a product is required to be free from preservatives and is to be in-pack pasteurised, preservatives should always be used in conjunction with pasteurisation when the ingredients indicate a particular risk of spoilage. In practice it is possible to produce simple flavoured soft drinks without pasteurisation but with preservatives, even when sugar is used as a sweetener, provided the ingredients used do not carry an undue level of microbial contamination and that the product is manufactured in a plant with a good level of hygiene. However, the incorporation of any fruit juice or other ingredient that could present micro-organisms with a supply of suitable nutrients should always indicate the use of preservatives in conjunction with flash or in-pack pasteurisation. If, for marketing reasons, a product is produced free from preservatives and is likely to be stored after opening for any reason, appropriate warnings should be clearly indicated on the label that tell the consumer to store an opened and unconsumed product in a refrigerator for a very limited period of time.
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Unpasteurised products that are stored at ambient temperature after opening are likely to ferment rapidly and, if the container is sealed, may cause it to explode. The use of any raw materials that may be heavily contaminated is to be avoided in all circumstances, as even with pasteurisation there may be a residual level of micro-organisms in the product that will not be controllable by preservatives. 2.7.4 Do preservatives in product deteriorate with time? The preservatives permitted in soft drinks must be added at the time of manufacture. Their primary purpose is to prevent the growth of any residual levels of micro-organisms that are in the packed product after any pasteurisation and filling operations. In consequence, the principal need for the effects of preservatives is in the immediate period after filling has taken place. The exception to this is for products that are likely to be left opened and partly consumed after filling, a situation that mainly relates to dilute-to-taste (i.e. concentrated) soft drinks. If sulphur dioxide (SO2) is used by direct addition to concentrated drinks or by carry-over at the permitted low level from products containing fruit ingredients, it will disappear from the product, depending on the initial level used. At carry-over levels (20 mg/L) it will usually be undetectable within one to two weeks, although at the levels permitted in concentrates the preservative will normally be detectable for some months, depending on the conditions of storage. Some of the SO2 will be released into the product headspace where it performs a very useful function, particularly in uncarbonated drinks, of preventing the development of any mould spores on the surface of the product. Sulphur dioxide can also combine loosely with sugars in product when it is described as `bound' SO2. Dimethyl dicarbonate (trade name Velcorin) relies for its effectiveness on its rapid breakdown, immediately after addition, to methanol and carbon dioxide. Both benzoic and sorbic acids can be expected to remain in the product for the duration of its shelf-life, although breakdown can occur. Of particular note is that some residual micro-organisms appear to metabolise these preservatives, thus effectively neutralising their preservative ability. Benzoic acid has also been found to react with any ascorbic acid in a product to produce benzene, and significant levels have been reported. The presence of measurable levels of benzene is likely to trigger a product recall. 2.7.5 Does dimethyl dicarbonate (DMDC) (trade name Velcorin) have to be declared as a preservative? In the United Kingdom, food labelling is regulated by statute, currently the Food Labelling Regulations 1996 as amended, and requires a list of ingredients to be displayed on the label. Whilst it is clear that when Velcorin is added, usually by direct injection to the soft drink in view of its hazardous nature, it should be described as an ingredient, a different view may be formed on the basis of Regulation 13 of the above statute. Section 13(2) states `Subject to Regulation 16, water and volatile products which are added as ingredients shall be listed in
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order of their weight in the finished product, the weight being calculated in the case of water by deducting from the total weight of the finished product, the total weight of the other ingredients used' (Regulation 16 deals with water alone). Reference to the UK Miscellaneous Food Additives Regulations 1995 as amended shows, in Part C of the accompanying schedule, that dimethyl dicarbonate is permitted for use in non-alcoholic soft drinks at the level of 250 mg/L `ingoing amount, residues not detectable'. Since it is permitted only on this basis of no residue being detectable, it could be argued on the basis of Regulation 13 of the Labelling Regulations above that if Velcorin is not detectable it cannot logically be listed. Manufacturers should seek the opinion of a suitably qualified lawyer if they wish to avoid mentioning Velcorin in the list of ingredients until such time as the matter is resolved by the courts. In the absence of any other advice, it would be prudent to declare dimethyl dicarbonate in the list of ingredients of a product. In countries other than the United Kingdom, Velcorin users should consult a suitably qualified lawyer to interpret the appropriate legislation. It should be noted that some UK enforcement authorities will check soft drinks for their methanol content. Methanol is a breakdown product of DMDC and can be used to estimate use of the preservative. However, methanol can also arise as a breakdown product of pectin and may be present if fruit juices are used as an ingredient. 2.7.6 Why will some local authorities not purchase products containing benzoic acid? Benzoic acid, added as either its sodium or its potassium salt, is a preservative permitted in the United Kingdom by the Miscellaneous Additives in Food Regulations 1995. It is necessary to use preservatives in some soft drinks to ensure the safety of the product by protecting it from spoilage micro-organisms. Benzoic acid has been widely tested (see 2.6.6) and accepted as safe by the European Union and United Kingdom authorities. Any refusal to purchase products containing this preservative is therefore a matter of a condition of a commercial contract rather than because benzoic acid is in any way not permitted for use in soft drinks. The authorisation and conditions of use of preservatives are governed in the European Union by Directive 95/2/EC of the European Parliament and Council of 20 February 1995 on Food Additives other than Colours and Sweeteners. There has been much public concern that some food additives cause adverse reactions, although investigations show that it is mostly based on misconception rather than on identifiable adverse reactions. Preservatives have rarely been shown to cause true allergenic (immunological) reactions. Among the food additives reported to cause adverse reactions are benzoic acid and its derivatives (E210±213), which may trigger asthma characterised by breathing difficulties, shortness of breath, wheezing and coughing in sensitive (i.e. asthmatic) individuals. Most local authority purchases are for supply to schools and other
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places where young or vulnerable individuals may consume the products. The provision of appropriate labelling is accepted by the UK government as an appropriate way of notifying the public of the presence of food additives, thus enabling informed choice to be made by the consumer. Individual local authorities may have their own specific reasons for not wishing to purchase drinks containing benzoic acid. Where benzoic acid is not wanted in products, it can usually be replaced effectively by the use of sorbic acid. Sulphur dioxide is of similar concern because of adverse reaction but it is now not used in ready-to-drink products that are likely to be purchased by local authorities. 2.7.7 Why may both sorbic and benzoic acids be unsuitable for tea drinks? The first issue to resolve is whether the product in question is a soft drink containing a tea extract or a tea drink that is flavoured in a similar way to soft drinks. This book is primarily written to cover soft drinks (non-alcoholic flavoured drinks) rather than products based on tea or coffee, and is restricted to issues relating to the former. Sorbic and benzoic acids are both added to soft drinks before acidification in the form of either their sodium or potassium salts and in order to potentiate them the product is acidified, usually to a pH between 2.7 and 3.7. In general, the lower the pH the more effective is the preservative (either sorbic or benzoic acid). The addition of tea extracts (as distinct from tea flavours) is an interesting developmental area that has been and continues to be explored by product developers. The principal problem that is likely to be encountered is the physicochemical stability of the added tea extract. When such material is added to an acidic soft drink, a precipitate frequently forms, although this may take several weeks. To minimise this occurrence, formulators will often raise the pH of the overall product to provide a more stable medium. If pH values are raised to between 3.7 and 4.0 it is likely that tea drinks will be more stable but the effectiveness of the preservatives will be reduced. If the formulation and production of tea drinks are contemplated, the preferred route of preservation would be either aseptic packaging or in-pack pasteurisation at a maximum pH of 4.0.
2.8
Nutraceutical ingredients
2.8.1 What are nutraceutical ingredients; how can I use them and how should they be labelled? `Nutraceutical' is used to refer to ingredients that are nutrients with possible pharmaceutical effects. They are used as ingredients in drinks that are claimed to have functional benefits in addition to being thirst quenching. They have become more popular as consumers' focus has moved towards drinks perceived to be more healthy.
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Vitamins and minerals The most popular and commonly used ingredients in such drinks are vitamins, minerals and antioxidants. Note that some vitamins are also antioxidants, e.g. Vitamins C and E. A popular combination is known as ACE, i.e. vitamins A, C and E. Vitamin A is added to soft drinks as betacarotene, which is known as provitamin A because it is converted to vitamin A in the body. B vitamins are frequently added to sports drinks as they are associated with carbohydrate metabolism. Vitamin B1 is mandatory for sports drinks in France. The most commonly added mineral is calcium, which is associated with bone and teeth health, but other minerals such as zinc are also used. Sodium is the mineral added to sports drinks as that is the key mineral lost in perspiration. In the EU, addition of nutrients is covered by Regulation (EC) 1925/2006. If any vitamins or minerals are added to a food or drink then full nutritional labelling (Group 2) must be used. For any claim regarding addition of a vitamin or mineral to be made, a `significant amount' must be added. A significant amount is defined as at least 15% of the Recommended Daily Allowance (RDA) per 100 ml, or per portion if a single-serve pack. At the time of writing the RDAs are under review in the EU as part of the revision of the Nutrition Labelling Regulations. Many are to be changed and new RDAs will be established for many minerals, e.g. potassium. The revised list of RDAs for vitamins and minerals is given below. Companies will have a transition period of four years to amend their existing labels and products. Vitamins and minerals which may be declared and their recommended daily allowances (RDAs) Vitamin A Vitamin D Vitamin E Vitamin K Vitamin C Thiamin Riboflavin Niacin Vitamin B6 Folic acid Vitamin B12 Biotin Pantothenic acid Potassium
800 g 5 g 12 mg 75 g 80 mg 1.1 mg 1.4 mg 16 mg 1.4 mg 200 g 2.5 g 50 g 6 mg 2000 mg
Chloride Calcium Phosphorus Magnesium Iron Zinc Copper Manganese Fluoride Selenium Chromium Molybdenum Iodine
800 mg 800 mg 700 mg 375 mg 14 mg 10 mg 1 mg 2 mg 3.5 mg 55 g 40 g 50 g 150 g
As a rule, 15% of the recommended allowance specified in this table supplied by 100 g or 100 ml or per package if the package contains only a single portion, should be taken into consideration in deciding what constitutes a significant amount. Directive 2008/100/EC amends Directive 90/496/EEC and comes into force on 31 October 2009. The above RDAs will become mandatory in the EU from 31 October 2012.
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Antioxidants It is claimed that oxidising free radicals are damaging to the body and are a cause of ageing. Antioxidants which will remove free radicals are therefore considered to be beneficial for a whole range of age-related diseases. Many botanicals (fruits and berries) are high in antioxidants and are used to manufacture `healthy' drinks. The most popular ones are pomegranate, blueberries and red (or purple) grape. Green tea and grape seed extract are also reputed to be high in antioxidants. It is claimed that one reason a Mediterraneanstyle diet is healthy is due to the high content of fruits, vegetables and red wine, which are high in antioxidants. Other ingredients There is a growing list of other ingredients that are added to drinks for beneficial purposes: · Fibre such as fructo-oligosaccharides is claimed to benefit the gut flora. · Omega-3 oil can be incorporated into a flavour emulsion (claimed to aid brain function, etc.). · Stanol or sterol esters can be added to reduce cholesterol levels in the blood. · Some ingredients extracted from fish are claimed to enhance skin smoothness and elasticity. The list grows almost daily. Labelling The labelling of functional drinks falls under the Nutrition and Health Claims Regulations, Regulation (EC) 1924/2006, which came into force on 1 July 2007 and are being implemented in stages over a period of several years. Article 14 requires that in order to make a health claim a scientific dossier substantiating the claim must be approved by EFSA and the EU Commission. A list of generally accepted claims currently in use is being drawn up by EFSA. This will be published in 2009 for implementation in 2010. Only health claims that have been formally approved will be permitted. A list of nutrient profiles is also being drawn up to which a food must comply in order to make a health claim. It is possible that drinks above a specified sugar content will be prohibited from making health claims. Nutrition claims will be permitted, e.g. contains vitamin C or with added calcium. However, if a nutrient exceeds the nutrient profile, that will have to be declared, for example `contains vitamin C ± high in sugar'. It is proposed that `contains antioxidants' should be considered as a health claim because `antioxidant' is a function, not an ingredient. The result of this legislation will be to severely limit the health claims that can be made for food and drinks.
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2.9
Miscellaneous additives
2.9.1 What miscellaneous additives can I use in a product and what functions do they perform? At the time of writing the use of all additives is controlled by three EU Directives, which are transcribed into UK legislation as in the table below: EU legislation
UK legislation
Sweeteners Directive 94/35/EC
Sweeteners Regulations 1995 SI No. 3123
Colours Directive 94/36/EC
Colours Regulations 1995 SI No. 3124
Miscellaneous Food Additives Directive 95/2/EC
Miscellaneous Additives Regulations 1995 SI No. 3187
The Miscellaneous Additives Regulations (MAD) control the use of all additives other than colours and sweeteners. This situation will change when the Food Improvement Agents Package (FIAP) combines the control of all additives into one regulation. Other regulations in the package will cover enzymes, flavourings and procedures. The additives that can be used in soft drinks are listed together with their maximum permitted usage rates. There are eight categories of additives permitted for use in soft drinks, listed in the Food Labelling Regulations 1996: · · · · · · · ·
Acids Acidity regulators Antifoam Antioxidants Colourings Preservatives Stabilisers Sweeteners.
Additives must be listed in the ingredients list under their appropriate functional category. · Acids/acidity regulators These are used to control the pH and total acidity of a drink. Acidity (sharpness) is a fundamental characteristic of a soft drink. The balance between sweetness and sharpness is known as the Brix Acid Ratio and is a key parameter in the formulation of a drink. · Antifoam The only permitted antifoam is dimethyl polysiloxane (E900). It is permitted at up to 10 mg/L to prevent head formation. · Antioxidants Many flavours and fruit materials are oxidised by oxygen from the atmosphere to form unpleasant stale tastes. In soft drinks ascorbic acid (E300) is added to protect the flavour from staleness.
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· Preservatives Soft drinks, like other foods, are subject to microbial spoilage by yeasts, moulds and bacteria. The growth of these organisms can be inhibited by addition of the preservatives benzoic acid or sorbic acid. Sulphur dioxide is also permitted to be used in fruit cordials and squashes and some glucose drinks. The permitted uses and maximum levels are listed in the regulations. · Stabilisers Cloudy fruit juices such as orange when used in drinks have a tendency to separate and the fruit pulp settles to the bottom. This can be much reduced and the stability and appearance of the drink improved by addition of a stabiliser such as pectin. Sugar provides considerable `thickness and mouthfeel' to a drink and when it is replaced by a high-intensity sweetener the drink can lack `body' in the mouth. This can be restored by the use of a thickener such as pectin. There are also a number of speciality gums, e.g. guar, carob, xanthan, etc., that can be used. · Sweeteners (Sections 2.3 and 2.4) and colourings (Section 2.6) were discussed earlier in this chapter. 2.9.2 If an additive is used as a process aid, does it have to be declared on the label? Processing aids do not have to be declared in the ingredients list. Processing aids are defined in the Food Labelling Regulations 1996 as `any substance not consumed as a food by itself, intentionally used in the processing of raw materials, foods or their ingredients, to fulfil a certain technological purpose during treatment or processing, and which may result in the unintentional but technically unavoidable presence of residues of the substance or its derivatives in the final product, provided that these residues do not present any health risk and do not have any technological effect on the finished product.' Provided that the additive and its usage meet this definition, it does not have to be declared. It is important to note, however, that allergen labelling is an exception to this. The presence of any allergen, as defined by allergen labelling legislation, must be declared even if it occurs as a processing aid. 2.9.3 Is there an industry standard for carbon dioxide? Yes. Following problems with contaminated CO2 in the UK in 1998, detailed specifications were adopted for food-grade CO2. In the USA the International Society of Beverage Technologists (ISBT), and in the EU the European Industrial Gases Association (EIGA), have produced specifications that are extremely similar. Carbon dioxide supplied in the UK for food/drink use should comply with the EIGA specification Doc 70/99/E. In 2000 the British Compressed Gases Association (BCGA) published Guidance Notes GN10 on the `Implementation of EIGA Standards'. The BCGA has also produced a Code of Practice for delivery and storage facilities for liquid CO2 at food/beverage plants, CP26 User's Premises' Revision 1: 1999.
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Potential contaminants are dependent upon the origin of the CO2. In the UK some CO2 is obtained from fermentation but the major source is as a by-product of the Haber process used for nitrogen fixation in the manufacture of fertilisers. The major potential contaminants are aromatic hydrocarbons. The maximum limit for benzene in CO2 used in drinks is 20 g/kg (ppb). 2.9.4 How is carbonation measured? Carbonation is measured as either `volumes' or g/litre. 1 volume means one litre of CO2 in 1 litre of drink. This is equivalent to 1.96 g/litre (normally quoted as 2 g/L). A typical carbonated soft drink contains approximately 3±4 volumes (6± 8 g/L) CO2. Carbonation is usually measured in soft drinks by measuring the pressure in the container at a known temperature. The pressure inside a container (can or bottle) is dependent upon the level of dissolved CO2 and the temperature. Water at 0 ëC will dissolve approximately 3.6 g/L CO2. At higher concentrations or higher temperatures, elevated pressure is required to retain the CO2 in solution. The standard instrument used by the soft drinks industry for measurement of carbonation is a Zahm CO2 tester. This consists of a strong hollow `needle' and a rubber seal connected to a pressure gauge. The needle is used to pierce the bottle cap or can base. The bottle or can is shaken vigorously to maximise the pressure and the maximum achieved pressure is recorded. The temperature of the drink is measured. The presence of dissolved air/nitrogen and of air/nitrogen in the headspace causes significant inaccuracy by increasing the measured pressure, but a correction can be made. The evolved gas is passed into a burette full of sodium hydroxide solution. This dissolves the CO2 and permits the volume of dissolved air/nitrogen to be measured. A correction can then be applied to the measured pressure. This is known as a Zahm±Nagel tester and was developed by the Zahm & Nagel Company, Inc. of New York. The CO2 content is read from a chart of temperature against pressure. Some companies use a `snift' method. The pressure is initially released (snifted) to flush air out of the headspace. The pack is then shaken and the maximum pressure noted. Note that the standard chart was derived using CO2 dissolved in water and the presence of dissolved solids and pH will affect the result slightly. However, the accuracy is sufficient for routine control purposes. Colorimetric methods for measurement of CO2 are available but are not generally used by the soft drinks industry as they are prone to interference in strongly coloured soft drinks and the pressure measuring method is very simple. 2.9.5 How are additives in ingredients declared? The Food Labelling Regulations 1996 (FLR) require that all ingredients must be listed in decreasing order (by weight) in the ingredients list. However, provision is made in the FLR for processing aids, which were defined in 2.9.1.
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It is not necessary to declare an additive that is derived from an ingredient and performs no technological function in the finished product. If the additive does perform a function in the finished product, e.g. as a colour, preservative, etc., then it must be declared in the ingredients list. Allergen labelling regulations require that any additive derived from a list of potentially allergenic sources, e.g. wheat, milk, fish, etc., must be identified on the label, e.g. contains wheat. Additives used in flavourings, e.g. solvents, are not required to be listed in the ingredients list. 2.9.6 Can I use antifoam? Yes, it is permitted to use dimethyl polysiloxane (E900) at a level up to 10 mg/L in order to reduce the formation of a stable foam during processing (see FLR 1996). Note that the use of antifoam may not be particularly successful and it may be preferable to identify and remove the cause of foam formation. Possible causes of foam formation include high levels of dissolved nitrogen, for example due to nitrogen sparging to reduce dissolved oxygen levels, use of intense sweeteners, and high levels of certain fruit juices/pureÂes. In carbonated products it is important to distinguish between `foaming' (formation of a stable head of foam) and `gushing' (rapid release of CO2). The presence of antifoam in carbonated products may exacerbate gushing by reducing the surface tension of the product and accelerating the release of dissolved CO2.
3 Manufacture of soft drinks and fruit juices Abstract: This chapter lists and answers key questions relating to the manufacture of soft drinks and fruit juices. It covers ingredient sourcing and storage, mixing and compounding, pasteurisation and homogenisation, filling, secondary packing and storage. Key words: soft drinks, fruit juices, mixing, compounding, pasteurisation, homogenisation, filling, secondary packing, storage.
3.1
Ingredient sourcing and storage
3.1.1 How much responsibility for ingredient quality can be transferred to the supplier? The supplier is responsible for the quality of the materials supplied by him. Materials must be of an acceptable quality and `fit for purpose'. Whilst in theory a supplier is responsible for the quality of his product and should carry product insurance, in practice the amount of recompense you are able to reclaim may be limited and the damage to your company's good reputation may be difficult to repair. The greatest risk arises from relatively low-cost basic ingredients (e.g. botanicals) which are used at low levels in a broad range of products, e.g. contamination of guar gum by dioxins. It is estimated that the presence of the red colouring Sudan 1 in chilli powder cost the UK food industry almost £100 million. It is essential that the purchaser agrees with the supplier a sound contract for a fully specified material, i.e. covering all product-critical parameters plus inclusion of a `catch-all' phrase such as `must comply with all EU and national food regulations'. Certificates of conformance for batches should be provided by the supplier. Manufacturers must depend to a large extent on their suppliers; it is
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impossible for a manufacturer to check every batch delivered for everything that could possibly be wrong. Suppliers must do HACCP and a full risk assessment for all the products that they manufacture, and drinks producers must audit suppliers and use only those they consider to be totally reliable. Compliance with manufacturing standards such as BRC Technical Standard and/or ISO standards is desirable. 3.1.2 What storage conditions should I use for ingredients? The storage conditions required are entirely dependent upon the type of ingredient being stored. The supplier of the ingredient should specify the preferred storage conditions. As a general rule ingredients, like most foods, should be stored in a cool, dry, dark place. However, there are exceptions, for example glucose syrups must be stored warm to prevent solidification and many fruit juices are stored deep frozen to prevent microbiological spoilage. Aseptically packed juices require only chill storage. Many finely powdered ingredients are hygroscopic (absorb moisture from the atmosphere) and will `cake' (form solid lumps) unless stored in well-sealed conditions. Such powdered ingredients are usually supplied in sacks or drums, typically 25 kg. These must be stored in clean dry conditions free from any pests. Adequate steps must be taken to ensure the absence of insects, rodents, etc. Many flavourings are easily oxidised and should be protected from air, particularly if a container is being regularly opened to extract a small quantity over a long period. In such circumstances it may be preferable to purchase the flavour in smaller quantities. Alternatively the headspace may be purged with nitrogen (or CO2) in order to exclude air. Flavourings should only be handled in a well-ventilated area due to their volatile character. Also note that some flavourings are highly flammable due to the solvents present and bulk quantities must only be handled in `flash-proof' areas, i.e. all electrical equipment (including light fittings) must be sealed and spark-proofed. 3.1.3 Are compound ingredients best outsourced or mixed locally? This will depend upon individual circumstances and a full and detailed commercial evaluation should be undertaken before a final decision is taken. At first sight it may appear preferable to have the compounding process, and hence total control, `in-house' and one would presume that this would also be the cheapest option. However, outsourcing can offer advantages. The compound ingredient may require specialist equipment, e.g. a homogeniser or tubular pasteuriser, and/ or specialist operators. This could be an expensive investment which may not be fully utilised if only relatively small quantities of compounds are being prepared. Outsourcing the operation to a flavour company or specialist compounder may be both simpler and cheaper. If the compound is used in large volumes and/or is strategically important, production may be divided between
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Soft drink and fruit juice problems solved
two suppliers in order to provide security and flexibility of supply. The use of outsourcing may also provide better access to alternative raw material supplies, and to product and technological developments, than is available in-house. During recent years there has been a significant move in the soft drinks industry towards outsourcing of peripheral activities such as compounding of ingredients as manufacturers have focused on core activities. 3.1.4 What are the best ways of storing carbon dioxide, sugar, fruit juices, flavours and other additives? Carbon dioxide is usually purchased as bulk liquid and delivered by tanker. Liquid CO2 is an extremely hazardous material requiring expert advice and specialist facilities for its storage. Liquid CO2 boils at a temperature of ÿ78 ëC and is normally stored in bulk at a temperature of about ÿ17 ëC and a pressure of 20 bar (280 psi). The liquid CO2 is drawn off via an evaporator as required. The British Compressed Gases Association (BCGA) has published a Code of Practice for the delivery and storage of liquid CO2 (CP 26 Users' Premises Revision 1: 1999). Provisions must be in place to ensure that no contamination can pass back from the factory storage to the road tanker during off-loading. Manufacturers of liquid CO2 will not deliver to a site unless they have previously approved the handling and storage facilities. Bulk fruit juices are usually stored either frozen (at about ÿ10 ëC) or aseptically in order to prevent microbiological spoilage. If the fruit juices are intended for use as ingredients in other products, e.g. in juice drinks, they are sometimes preserved with benzoic acid or sulphur dioxide (added as sodium benzoate or sodium metabisulphite). Lemon and lime juices are permitted to be preserved with up to 350 mg/L SO2. However, with improvements in the technology for handling frozen and aseptic juices, the use of preservatives has decreased over recent years. The storage of bulk carbohydrates requires very specialised equipment (see 3.3.6). 3.1.5 How do I avoid product `drift'? Maintaining the required product specifications for analytical parameters such as Brix, acidity or carbonation is relatively straightforward using simple laboratory equipment. A synthetic or nature identical flavour manufactured from `flavour chemicals' to a defined formulation is also relatively simple to maintain. However, maintaining the organoleptic character of a complex natural botanical flavouring over a period of many years is much more difficult to achieve. It is essential to define the organoleptic character of the flavour both analytically and by source as fully as possible. The key flavour chemicals can be identified analytically using techniques such as chromatography and mass spectrometry and can be monitored periodically to confirm that no significant changes occur. Chromatographic `fingerprinting' can be used as a routine tool to monitor consistency and permit any changes to be further investigated and corrected. Changing the source (geographical origin) of botanical ingredients can result in
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significant changes to the flavour. Also suppliers or flavour companies may change the origin of botanicals either for economic reasons or due to climatic conditions impacting on availability. Any supply change must be carefully monitored to ensure that flavour change is minimised. In addition to analytical monitoring, the use of a trained taste panel will help to maintain the organoleptic character of key products. The panel must be effectively trained and its performance monitored against known standards. 3.1.6 What standards should I operate to and what standards should I demand from my suppliers? The most commonly requested standard for manufacturers is the BRC Technical Standard. This is demanded by most retailers from their suppliers. The major standards needed by suppliers of both raw materials and finished drinks are the ISO standards: · · · ·
ISO ISO ISO ISO
9001 ± research and development standard 9002 ± quality management standard 14000 ± environmental standard 28000 ± ethical standard.
Some companies demand that their fruit juice suppliers are members of the SGF/ IRMA scheme. This requires that the juice processors are subject to auditing and to analysis of their juices to confirm authenticity. 3.1.7 Do some ingredients demand special production plant? Because of their particular physical and/or chemical properties, some ingredients require specialised production plant in order to be successfully incorporated into the finished product. Fruit juices Single-strength frozen fruit juices freeze completely solid and the blocks must be crushed and thawed in specially designed steam-heated crushers before use. Fruit juices with high levels of particulates (cells and pulp) require special handling for both pumping and pasteurisation, for example the use of positive displacement pumps and wide plate or tubular pasteurisers which will not damage the cells or become blocked. Fruit drinks containing whole fruit (comminute) have a tendency to separate. The fruit pulp sinks to the bottom. This can be minimised by homogenisation. If the fruit, beta-carotene and stabiliser/thickener are thoroughly mixed and homogenised together into a compound, this tends to improve their physical stability and minimise their tendency to separate. Powders Many powders exhibit hydrophobic properties and require careful addition to water in order to avoid the formation of lumps which are almost impossible to
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dissolve. This applies particularly to gums and stabilisers, e.g. starches, pectins and sodium carboxymethylcellulose. These require the use of a high-shear mixer in order to homogenise the powder into the water in a very finely dispersed form. This dispersion may then be dissolved by heating. The preferable form of high-shear mixer is a continuous flow-through type, as manufactured by Silverson, for example. Dimethyl dicarbonate (DMDC) This liquid is injected into drinks immediately prior to the filler in order to sterilise it and the sealed packaging. It must be accurately dosed into the product stream by means of a dedicated injector system. 3.1.8 What do I need to specify on a supplier contract? A purchase contract is in two parts, one applicable to the material being purchased to ensure that it meets all your technical/quality/production requirements, and one applicable to the commercial transaction itself. Product specification A purchase contract should specify (or make reference to) all factors and parameters which would adversely impact on the nature of your product if they were not complied with. For example, for a fruit juice a specification should include microbiological standards, including absence of Z. baillii and Alicyclobacillus. If required, limits can be placed upon colour by specifying the absorbance range at various wavelengths. It may be desirable to specify absence of enzyme activity, in particular pectinesterase activity, to ensure cloud stability. If the appearance of the product is important then cloud stability, pulp content and particle size distribution should also be specified. It must be remembered, however, that an extremely tight specification requirement will make the material more difficult to source (particularly for natural products) and therefore probably more expensive. For powders it may be important to also specify moisture content, particle size distribution and packaging requirements, which can be important for handling performance in production. Compliance with all EU/UK legal requirements should be included. This would cover presence of contaminants such as pesticides, heavy metals, mycotoxins, etc. Moisture content is important. An increase from 1% to 4% may not only impact on your production process, it also represents a 3% price increase! Commercial contract The commercial contract should cover all the financial/commercial aspects of the transaction from the basic price and quantity to delivery, responsibility for damage in transit, delivery time, payment terms, etc.
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3.1.9 Do I need to audit suppliers? The decision on whether or not to audit a supplier would depend upon the criticality of the item purchased and the availability of resources. A manufacturer must balance the risk of an ingredient problem against the cost (time and money) involved in auditing. Third party auditing schemes are available and represent a good compromise. For example, SGF, based in Frankfurt, operates an auditing system for fruit juice processors worldwide. Member companies are audited for their authenticity and production standards, and ethical issues such as environmental and employment concerns have recently been included. Remote plants in developing countries are perhaps those most in need of auditing but are least likely to be audited because of the cost and time expended. It is important to audit such plants or to use an independent auditor.
3.2
Mixing, compounding and related problems
3.2.1 What type of mixing plant is ideal for soft drinks? There is no one ideal mixing plant. The design depends upon what is being mixed. All materials used must of course comply with the materials in contact with food regulations. Stainless steel is the preferred material because of its resistance to attack, particularly by cleaning agents such as hypochlorite or ozone. Stainless steel grade 316 is generally considered to be the best material for general use. It is important to achieve thorough mixing without entraining air, which can oxidise susceptible flavours and cause filling problems, especially for carbonated drinks. The two main types of stirrers are large paddles for slow mixing/ stirring of viscous solutions, and rapid `propeller'-type stirrers for dissolving powders or rapid stirring of less viscous solutions. Specialised mixing plant, e.g. homogenisers, may be required for effective dissolution of powders such as gums and stabilisers. Most soft drinks plants operate on a batch mixing principle. A batch of syrup is prepared from the individual ingredients, quality control checked and blended with water to make the finished product. It is essential that the rate of syrup manufacture, mixing and quality control checking is rapid enough to keep pace with the rate of bottling to avoid downtime on the line. In order to simplify the syrup room operation, key components are often pre-blended in the form of a `compound'. This would typically include fruit material, colours, flavours and sweeteners (but not aspartame). At its extreme this approach has been developed into a fully automated blending system. The major ingredients ± sugar, compound, water and CO2 ± are fed into a continuous blender and then directly to the bottling line. This type of process is better suited to long runs of one type of product rather than to those requiring many frequent flavour changes. The syrup is blended with water to the desired finished strength using a continuous blending system such as a Mojonnier mixer.
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Soft drink and fruit juice problems solved
3.2.2 Is there an ideal order of addition for ingredients? The order of addition is important in some circumstances. Sodium benzoate and potassium sorbate must be dissolved in a large volume of water before the addition of acid (citric or malic) or fruit juice. If acid is added to a batch it will be extremely difficult to then dissolve benzoate or sorbate. Benzoic acid or sorbic acid may precipitate and not redissolve. It is normal practice to add a significant proportion of the required water initially to aid mixing. Flavourings are usually added last, into the maximum volume possible prior to final make-up. This is because many flavour components are only very sparingly soluble in water. It is essential to add the flavour slowly with much stirring into the maximum volume of product, especially if oils having a low water solubility are present. This avoids localised high concentrations of flavour components which will then separate out of solution. This is frequently the cause of an oily film of flavour oils forming on the surface of a syrup batch. Cloudifier, if added, should also be added in the same manner as flavourings. DMDC (E242) is injected into the package immediately prior to the filler in order to sterilise the product and pack before it hydrolyses. 3.2.3 If undissolved materials remain in the syrup mix, what action should be taken? It is essential to identify the undissolved material and not to proceed further with production until this has been achieved. The material may be some form of contamination and it should not be assumed that it is merely an incompletely dissolved ingredient. Remove any undissolved material. If the material is found to be an undissolved ingredient, its identity and its shortfall in the syrup must be determined analytically and corrected. If the syrup has not yet been made up to the final volume, the missing ingredient may be simply dissolved in water and added. Alternatively, another batch of syrup may be made up with the ingredient concerned increased pro rata, and the two syrups blended. The undissolved material must be removed from the syrup in order to prevent particles of undissolved material occurring in individual bottles or cans. This could cause a localised concentration of the additive. Also the presence of even very small amounts of particulate material will make carbonated drinks very difficult to fill due to excessive fobbing. The most likely sources of undissolved materials are artificial sweetener, particularly aspartame, and benzoic and/or sorbic acids. If sodium benzoate or potassium sorbate is added to a mix without most of the water needed present, acidification will generate the free benzoic and sorbic acids at a level that exceeds their solubility in water. If this occurs, it is almost impossible to redissolve the free acid(s). (See also 3.2.6.)
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3.2.4 What steps should be taken to minimise the introduction of air into the product? The presence of air (in particular oxygen) in some products can be very harmful. Oxygen will oxidise many flavours, accelerating the development of stale `off' notes in the product. It will also accelerate the browning of fruit colours. The presence of dissolved air will also adversely affect the filling performance of carbonated drinks by encouraging the rapid breakout of CO2 with consequent fobbing. The mixing of ingredients needs to be sufficiently vigorous to ensure thorough mixing but must be such that it does not entrain air into the liquid. The use of correctly designed stirrers and correct stirring speeds for the purpose is important. For particularly oxygen-sensitive products a `blanket' of nitrogen or CO2 can be maintained in the tank headspace. For still products this can also be done throughout the filling process. If excessive dissolution of CO2 is encountered, nitrogen (N2) should be used. However, dissolved N2 will encourage increased foam (head) production in products with a tendency to do so, e.g. fruit juices. Dissolution of N2 is used in the brewing industry to improve the head formation and retention in beers. 3.2.5 Why do I have an oily film on the surface of my syrup? The presence of an oily film floating on the surface of a syrup is due to incomplete dissolution/dispersion of flavour components into the bulk of the syrup. Many flavour components are high molecular weight and only sparingly soluble in water. In the concentrated flavouring they are dissolved in a suitable solvent, e.g. ethanol. The flavouring must be mixed slowly and thoroughly into the tank of product to avoid localised concentrations occurring where the solubility of the flavouring in water is exceeded. The solution to the problem is to improve the thoroughness of the mixing process by adding the flavouring more slowly and/or installing a better mixing system. Alternatively it may be possible to improve the solubility of the flavouring by reformulation, though this would probably affect the taste of the product. This problem most commonly occurs with flavours derived from citrus oils. 3.2.6 What is the most likely cause of white flecks on the surface of my syrup during manufacture? The presence of material on the surface of a product is almost always due to either undissolved material or an ingredient that has come out of solution. Artificial sweeteners, particularly aspartame, can be difficult to dissolve and can give rise to this problem. A more likely cause, if either sorbates or benzoates are used as preservatives, is that the amount of preservative used has been dissolved in too small a quantity of water before the addition of any acidic ingredient such as citric acid. Whilst both sodium benzoate and potassium sorbate are extremely
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Soft drink and fruit juice problems solved
soluble in water, the corresponding free acids, that are the effective preservatives, have much more limited solubility in water of about 1.5±2.0 g/L. To avoid this problem occurring, the volume of a syrup during manufacture should be around at least 75±80% of the final amount before it is acidified. For the same reason it is extremely difficult to add any further quantities of either sorbate or benzoate to a product after it has been acidified. 3.2.7 Can I make milk/yoghurt and fruit juice drinks in my soft drinks plant? The use of dairy and/or fruit juices in drinks presents a number of additional requirements. The chief of these is the requirement for very much more stringent microbiological control. Different storage, handling and cleaning regimes are also needed. Storage and handling of the raw materials should be in line with the suppliers' advice. Fruit juices are stored either frozen or chilled aseptic. Particular care must be taken with handling and storage of dairy-based ingredients due to the generally higher pH and much increased microbiological hazards associated with milk products. Dairy products with a pH less than 4.0, e.g. yoghurt, are easier to handle due to their lower microbiological sensitivity. Drinks containing a significant proportion of dairy ingredient and having pH greater than 4.0 must be treated as dairy products and processed accordingly. Proteins are likely to coat equipment and special cleaning regimes are needed, especially for pasteurisers. 3.2.8 Should I dissolve ingredients prior to addition? Practice varies between manufacturers but it is generally regarded as good practice to ensure that all ingredients are thoroughly dissolved prior to addition to the syrup tank. The solution can then be added to the batch tank through a fine-mesh filter. This enables the manufacturer to be sure that complete dissolution has occurred and no insoluble particulates are present. Some syrup tanks are specifically designed to enable the dissolution of ingredients. These usually employ a powerful propeller-type device low on the side of the tank to produce a strong turbulence across the base of the tank. Ingredients should not be dissolved directly into the syrup tank unless it has been specifically designed for this purpose. Sugar is usually added in large quantity (except for diet drinks) and is very slow to dissolve in cold water. It is therefore customary to make a sugar syrup separately (see 2.3.6). Solutions of citric/malic acids are available from the suppliers for large users. If these acids are to be dissolved on site it should be noted that the process of dissolution is endothermic and unless warm water or heated vessels are used the operation may take a considerable time. Flavourings are usually added last (see 3.2.5).
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3.2.9 Should turbulence be avoided during mixing? The mixing of ingredients to ensure an even concentration in the end product is a key stage in the manufacture of soft drinks or the reconstitution of concentrated juices. Mixing can usually be divided into five areas: liquid±solid dispersion, gas±liquid dispersion, liquid±liquid dispersion, the blending of miscible liquids and the production of fluid motion. These areas are all relevant to the mixing of soft drinks and fruit juices and all but gas±liquid dispersion are desirable. This latter process is generally to be avoided as it usually refers to the introduction of air into the mix by too vigorous a motion or an inappropriate mixing impeller. Impellers are either axial flow (marine propeller or fluid foil type) or radial flow (flat bladed). Most beverage manufacturers use axial flow impellers as they generally offer the most movement capacity per unit of power. Of the two types of axial flow impeller, the marine propeller type has a variable angle and an approximately constant pitch across the impeller face leading to a relatively uniform flow across the impeller periphery. The fluid foil type has a constant angle across the face and consequently a variable pitch. It is not normally as efficient in the mixing process. Most beverage manufacturers will have marine-type impellers and baffled tanks to produce a good flow pattern within the tank. There is usually a balance to be struck between getting an adequate flow within the mixing tank to achieve the required liquid±solid or liquid±liquid dispersion and avoiding the creation of such a vortex that draws in air and disperses it into the product. Air drawn into the product introduces oxygen and this invariably has subsequent damaging effects on the flavour or colour of the product. There must, however, be sufficient turbulence to dissolve or disperse all the desired ingredients. 3.2.10 How much automation should be installed? Before deciding on whether (or how much) to automate a process, a detailed cost/benefit analysis must be performed. The high capital cost and relative inflexibility of automation must be measured against its higher production efficiency and output. New products are frequently manufactured by means of manual labour until their performance in the marketplace can justify the investment in automated equipment, thereby reducing the capital risk of the launch. In general, the faster the operating speed of a filling line the less flexible it is. It may be preferable for a manufacturer to opt for a slower but more flexible facility. Changing the height of the packages being filled is very much easier than changing the diameter. It is therefore standard practice to maintain the same diameter and vary the height when designing a range of packs with different volumes. Changeover of a high-speed production line from one pack size to another can take several hours. Time is also required to get the line up to its normal efficiency. No such loss of production time is incurred with manual operations.
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Soft drink and fruit juice problems solved
3.2.11 Are there any special manufacturing issues that apply to pure fruit juices? Fruit and vegetable juices require specialist manufacturing processes due to their relative lack of both physical and microbiological robustness compared to standard soft drinks. Additives such as colours, preservatives and stabilisers are generally (with a very few special exceptions) not permitted, so the initial purchasing specification of the juice is critical to the appearance and performance of the finished product. Juices often require special physical handling also. They are generally of high viscosity, particularly when cold, and frequently have a high pulp content. These characteristics require specialist pumping (e.g. positive displacement pumps) and pasteurisation (e.g. tubular pasteuriser) equipment. Since preservatives are not permitted in fruit juices, ambient stable packs must be either hot filled, in-pack pasteurised or aseptically filled. Products can also have a short shelf-life and need to be maintained under chilled conditions. Such products are flash pasteurised under less severe conditions than ambient stable juices, cold filled, and then stored, distributed and sold via the cold chain. A shelf-life of several weeks can be achieved using this process. The less severe (lower temperature, shorter time) pasteurisation results in an improved flavour. It must be noted that vegetable juices, e.g. carrots, are not acid products. They have a pH significantly above 4. They are also potentially contaminated by soilborne organisms and are susceptible to pathogens, including Clostridium botulinum. Vegetable juices must be subjected to a much more severe pasteurisation regime than fruit juices, e.g. UHT, or blended with a fruit juice to reduce the pH below 4, immediately following initial production.
3.3
Pasteurisation, homogenisation and related issues
3.3.1 When is pasteurisation necessary? There is a strong argument for applying pasteurisation to all soft drinks and fruit juices as most products are at some risk of spoilage from micro-organisms. The most obvious exception is likely to arise in the preparation of freshly squeezed fruit juices that are marketed on the basis of no further processing after pressing. Such products have a very limited shelf-life but provided they are manufactured and packed in clean conditions and then stored cold (at around 5 ëC) an acceptable shelf-life may be achieved. The other products that are unlikely to need pasteurisation are carbonated drinks that are manufactured using flavourings without any fruit content. It is, for example, normally not necessary to pasteurise cola or lemonade syrups that are subsequently to be carbonated. Carbonated ready-to-drink products do achieve some degree of microbial protection from the presence of carbon dioxide gas in the headspace as well as from the effect of its pressure that will suppress the metabolism of most gas-producing yeasts. The presence of carbon dioxide will also suppress mould growth.
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Products that are most vulnerable to spoilage from micro-organisms are all products containing fruit, including dilute-to-taste soft drinks, and ready-todrink products that are uncarbonated. Unpasteurised pure fruit juices will start fermenting rapidly after pressing, particularly if they are not chilled, and pasteurisation should take place as rapidly as possible after pressing. In the case of fruit juices reconstituted from concentrates, pasteurisation is normally incorporated into the aseptic packaging process. Uncarbonated soft drinks are particularly vulnerable to spoilage from moulds as well as some bacteria, even when there is no juice content. Pasteurisation is also necessary for fruit juices to ensure physico-chemical stability. When juices are expressed from fruit, natural pectolytic enzymes are released and, if not destroyed by pasteurisation, will cause the product to separate into heavy sediment and a clear upper layer. 3.3.2 What pasteurisation conditions are needed and how can these be calculated? This response deals solely with the issue of thermal pasteurisation, although it is possible to achieve a pasteurisation effect by the use of pressure. Thermal pasteurisation is normally achieved by one of three techniques ± flash pasteurisation, in-pack pasteurisation and hot filling. Aseptic filling is usually associated with a linked flash pasteuriser. Pasteurisation is to be distinguished from the process of sterilisation where a temperature of around 121 ëC is normally reached and all normal micro-organisms are killed. Pasteurisation is used for products that have a pH value of 4.5 or less where the acidic conditions effectively prevent the growth of pathogenic organisms. However, some care needs to be exercised with products that have pH values that are in the region of 3.9±4.5 as it has been demonstrated that some pathogens (e.g. E. coli O157) can survive in such conditions. To determine the level of pasteurisation needed (in-pack or flash treatment) it is normal to refer to the number of pasteurisation units needed. No effective pasteurisation occurs below 60 ëC and by holding a product at that temperature for 1 minute it is said to have received 1 Pasteurisation Unit (PU). To calculate the number of pasteurisation units for any given time temperature relationship the following formula applies: Number of Pasteurisation Units (PUs) 1:389
tÿ60 time in minutes As an example, if a product is held for 20 minutes at 70 ëC (typical in-pack pasteurisation conditions): Number of PUs 1:389
70ÿ60 20 1:38910 20 26:73 20 534:6 PU
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Soft drink and fruit juice problems solved
A simplified approach is to accept that, for every rise of 7 ëC over 60 ëC, there is a 10-fold increase in the number of PUs, i.e.: · 60 ëC 1 PU/minute · 67 ëC 10 PU/minute · 74 ëC 100 PU/minute, etc. This is, however, difficult to interpolate if the simplified approach is used. In-pack pasteurisation, involving the use of a tunnel pasteuriser, is preferred for very high risk products such as those where no preservative is used, although if possible such products should be packed aseptically. The use of in-pack pasteurisation is normally limited by the containers to be employed as the technique is only really suitable for glass bottles and cans. To minimise thermal shock, most tunnel pasteurisers have a warm-up section to about 40±45 ëC, the actual pasteurising section and then one or more cooling sections. It is also good practice to air-dry the containers to ensure good label contact for glass or to prevent can corrosion. Care should be taken to ensure complete cooling of products as they can, if packed in close proximity, retain heat and effectively `cook'. This phenomenon is known as `stack burn'. An alternative approach for packed products of high risk is to hot fill. Product is heated, usually to about 75±80 ëC, and then filled into containers (usually prewarmed to avoid thermal shock). Filled containers are then closed and inverted on line to ensure complete contact of the hot product with the inside of the container and closure. Products are then cooled, using water sprays if possible, before being dried, labelled and placed into secondary packaging. 3.3.3 When is it desirable to homogenise a product? Homogenisation is the process by which a mixture of components is treated mechanically to give a uniform product that does not separate. Homogenisation is widely used in the dairy industry and rather less frequently in the manufacture of soft drinks or fruit juice products. Product is forced through the small openings of a homogenising valve formed by an appropriately designed stainless steel conical valve operating against a valve seat. Any globules of oily material are broken up as a result of shearing forces, or being forced against the wall of the valve and possible by cavitation and explosive decompression on being released from the valve. The most effective homogenisers rely on the use of positive displacement pumps that will operate at very high pressures. Rotary homogenisers that are placed into the mixing tank are rarely as effective as the piston type. The products that are most likely to require homogenisation are those containing oily flavours or essential oils (e.g. citrus oils). Such products are invariably whole fruit drinks that contain comminuted citrus. The level of citrus oils in comminutes can be over 1% and if used in dilute-to-taste or ready-todrink products they may give rise to unsightly oil rings. Some manufacturers will use permitted emulsifiers to assist in stabilising the end product, although
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experience shows that a homogenised citrus comminute will usually be very stable. The process of homogenisation is widely used in the manufacture of cloudy emulsions (with or without added flavour or colour) as these are designed to increase the cloudy appearance of end products and often to deliver colour and flavour as well. To produce a stable cloudy emulsion it is necessary to ensure that remaining oil globules are no larger than about 10 microns. When cloudy emulsions are used or when flavours are added to emulsified products, the effect of adding a solvent such as alcohol, present in a flavour, can sometimes break down otherwise stable emulsions. 3.3.4 What are the best types of pumps to use? Pumps are divided into dynamic and positive displacement types. The dynamic type operates by increasing the velocity of the fluid as it passes through a rotating impeller. Positive displacement types include pumps where a chamber is filled with liquid, to which pressure is applied, usually by a piston or diaphragm. Before a pump is selected the conditions under which it will be required to operate must be known. This will include the type of liquid, its density, temperature and viscosity. Flow rates will be required as well as inlet and outlet pressures and the presence of any suspended solids, corrosive or erosive materials will need to be accounted for. All pumps used for soft drinks or fruit juices should, as far as possible, be constructed to have contact parts of stainless steel (316 grade) or, in the case of diaphragm pumps, other inert material. Most pumps used are of the centrifugal type that are easily cleaned and can be replaced quickly. Some situations will require pumps of the self-priming type. There are other situations that require positive displacement pumps that can deliver at significant pressure. Pumps of the `Monopump' type are often very suitable as they typically have a stainless steel rotor working against an inert flexible stator. Diaphragm pumps offer the attraction of being of the positive displacement type with no rotary moving parts and, as they are invariably driven by compressed air, do not require an electrical supply. This may be a particular benefit if pumps are to be moved around frequently or are to be used in a hazardous atmosphere where zoning of electrical equipment is necessary. Pumps should be inspected regularly and any leaky seals or other worn parts replaced. 3.3.5 Are changes to the taste or appearance of a product likely as a result of pasteurisation? Thermal pasteurisation, by its very nature, involves heating a product for a shorter or longer period, and the effect of any heating on a soft drink or fruit juice usually produces some effect on the taste and occasionally the appearance. Unnecessary heating should always be avoided and any heat that is applied should be for the shortest possible period. As a consequence, it will be apparent
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that flash pasteurisation is, where possible, to be preferred to hot filling or inpack pasteurisation. Flash pasteurisation normally requires a heating period that may vary from a few seconds at 90±95 ëC to up to a minute at lower temperatures of 80±85 ëC, whereas hot filling and in-pack pasteurisation will typically expose a product to heating at slightly lower temperatures for 20 minutes or so at pasteurising temperatures and for 30±40 minutes overall. The least effect that any heating is likely to have is that of reducing very slightly any fresh taste and aroma characteristics. This may be noted when freshly squeezed juices are pasteurised and compared with unpasteurised product. However, the taste and aroma of unpasteurised juices will often deteriorate very quickly and what is regarded as a `light' pasteurisation will always preserve the characteristics of the original juice for much longer. The operation of flash pasteurisers usually incorporates a recirculation system that will automatically cut in when pasteurisation temperature falls below the set level or the packing unit is stopped for any reason. There is then a danger of product being passed through the heating unit several times and acquiring noticeable heat damage. Excess heating will firstly have the effect of significant loss of fresh aroma and if prolonged will allow a noticeable cooked flavour to develop. Most pasteurisation processes will not have a noticeable effect on product appearance, although occasionally some browning will occur. During the shelf-life of a product any excess heating of product that occurred during processing may affect the taste and appearance by causing premature development of a cooked or aged taste and a noticeable brown hue to the colour.
3.4
Filling operations and related issues
3.4.1 Do different filler types affect product quality? Filler types are generally related more to the type of packaging rather than to the product, although carbonated drinks require suitable equipment. The main packaging types are bottles and cans. The fillers used for bottles (glass or PET) and cans are invariably of rotary design and are usually of one of three types: · The volumetric filler which dispenses a fixed volume into a container · Counter pressure fillers that ensure carbon dioxide is maintained in solution in the product · Constant level fillers that ensure the bottle content is set to a predetermined level in the container. The other types of containers usually rely on delivering a predetermined quantity of liquid into the appropriate container. The purpose of filling is to transfer the bulk product into the unit volumes in which it is sold to the consumer without, as far as possible, allowing the ingress of oxygen or micro-organisms or, for carbonated drinks, the loss of CO2 gas or product. When products are to be packed aseptically, specialised equipment
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must be used to ensure that product is transferred to the container without contamination. Many manufacturers will adapt existing filling equipment to meet specific types of packaging, but increasingly filling plant and packaging are considered together to ensure that product is filled under the best possible conditions. 3.4.2 What regular quality checks should be made on fillers? The function of the filler is to transfer the bulk product into desired packages in the correct volume and without compromising its quality in any way. There are thus two principal quality considerations: to check that the filler is delivering the required amount from each of the filling heads, and to ensure that the filler is clean and free from mechanical defects. To check the delivery of the correct quantity and quality of product, samples should ideally be taken from each filling head in sequence over an agreed period of time. This task may be difficult, particularly if the equipment has a large number of filling heads, but provided appropriate records are kept it may be possible to maintain a satisfactory control record. In practice it is extremely difficult to take a sample from an identifiable filling head without stopping the operation, and most fillers do not allow the identification of individual heads in the marking system. General practice is to remove filled containers from the line and carry out the appropriate quantity and quality check. Coupled with records of filled containers, a bulk reconciliation of the number of filled containers compared with the volume of bulk product manufactured but taking into account historical filling line losses should identify any gross problem with filler operations. If necessary a detailed investigation can then be instigated. Provided the filler is cleaned according to the recommended schedule (see 3.4.3) no particular hygiene problems will usually be experienced. However, if complaints are received that suggest a microbial spoilage problem, from analysis of the number of complaints compared with the total volume produced in a batch, some indication can usually be obtained as to whether the problem relates to the bulk or to one or more filling or capping heads. Particular care should be taken when replacement parts are fitted to ensure adequate hygiene. The opportunity to check for any possible mechanical defects can also be taken at the same time. 3.4.3 What is a typical cleaning regime for a filler? Most modern filling systems incorporate clean-in-place (CIP) systems. Such systems normally operate automatically and remove the human element. A typical CIP system will operate on the following cycle: 1.
The filler and filling valves are rinsed for a set time using rinse water to drain. The rinse water will remove particulates and product residues. Rinse
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2. 3.
4. 5.
Soft drink and fruit juice problems solved water is often the final rinse from the preceding CIP operation as this conserves water. Approximately 1.5% w/v caustic soda solution at around 80 ëC (as recorded at the filler outlet) is circulated for 15 minutes. Caustic soda is then returned to the hot caustic tank through filters. Hot water at 75 ëC is then circulated for 15 minutes allowing the interface with the caustic to flow to drain. A conductivity probe is normally inserted within the circuit to ensure that all the caustic lye has been removed. Hot water is recirculated to conserve energy. Cold water, filtered to less than 2 microns absolute and exposed to ultraviolet irradiation, is used as a final rinse. Systems are often left with a proprietary sterilant in place until the next production is required. This is then flushed through using clean cold water until all traces of sterilant are removed.
Careful records of all CIP operations should be retained in case product problems arise and it becomes necessary to prove that cleaning was effective. Correct design of the filler, valves and CIP cups must ensure that all surfaces are effectively cleaned; this is assisted by ensuring that all surfaces are smooth and have large radii. Some operations carry out an occasional acidic wash and others use different proprietary sterilants to minimise any risk of micro-organisms becoming tolerant to a specific material. Many proprietary sterilants are based on chlorine, peracetic acid or quaternary ammonium compounds. 3.4.4 At what temperature should products be filled? Because relative density of a product is related to temperature, the colder a product is at filling, the greater the mass that will be filled. Since most packers fill by volume, filling at unnecessarily cold temperatures will, over a long period of time, consume more raw materials. There is, too, the cost of operating cooling machinery to provide excessive temperature reduction. However, carbonated drinks need to be subjected to rather more temperature control than noncarbonated products as their ability to hold CO2 is closely related to temperature. Most carbonated drinks will fill satisfactorily at around 10±12 ëC. In general, non-carbonated drinks can be filled at the ambient temperature, although in tropical conditions some cooling is usually necessary as products filled at temperatures of 30 ëC or more may begin to show signs of heat damage during a normal shelf-life. Products that are subjected to a pasteurisation process must be adequately cooled at least to below 25 ëC and preferably below 20 ëC. The required temperature will depend on the type of product and the equipment available. Most flash pasteurisers operate by recovering heat from already pasteurised product to provide the initial heating of incoming (as yet unpasteurised) product but then have a separate cooling circuit to reduce product temperature to the required
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level. Temperature reduction of product in tunnel pasteurisers is often more difficult to control, as they rely on heat transfer through the wall of the product container into the centre of a bottle rather than through a thin steel surface with only 2±4 mm thickness of product in a flash (plate) pasteuriser. The cooling process in a tunnel pasteuriser, which may be used for the full process or simply to provide cooling if products have been hot filled, relies on a series of water sprays that progressively reduce temperature and thus minimise thermal shock. 3.4.5 Why do some products froth (fob) and how can this be avoided? When carbonated drinks are in a closed container, there is equilibrium between the CO2 gas that is dissolved in the product and that in the headspace of the container. A sudden reduction in pressure, such as that experienced when the cap is released, or an increase in temperature, alters the temperature/pressure equilibrium, causing the gas±product mixture to become metastable. When this occurs, there is a spontaneous release of gas that gives rise to fobbing or frothing. Fobbing will become more pronounced if the mixture is shaken or agitated or if any small particulates are present in the product. The presence of dissolved air in a product is also likely to cause fobbing as air is much less soluble than CO2 and, on release of pressure in a container, provides nucleation sites for the release of dissolved carbon dioxide. This is one reason why levels of air should be kept to an absolute minimum in carbonated drinks. Fobbing can become a particular problem during the filling of carbonated soft drinks at the point in the filling cycle when the filled container is released from the filling head. If this is carried out suddenly there is a rapid drop in headspace gas pressure and severe fobbing is likely to result. To overcome this problem, fillers for carbonated drinks are designed to allow a brief settling period in the filling cycle. This occurs just before the liquid filling valve closes, thus allowing gas in the container headspace to escape in a controlled manner. This process is known as snifting. Other origins of fobbing include certain types of `lively' products such as cream soda, discontinuities in the walls of the container that cause the product to become agitated during filling, and the design of the filling valve, particularly if product containing fruit cells is being filled. Modern fillers fitted with swirl valves are of considerable assistance in minimising fobbing. Fobbing is to be avoided during filling as it will affect the quantity of product remaining in the bottle and can be a considerable irritation to the consumer of the product. 3.4.6 What is the average fill system (e-mark)? The average fill system, introduced into the United Kingdom in 1979, recognises the statistical nature of the filling process and allows packers to fill a proportion of product below the stated fill level, provided that on average the packs produced have an overall mean greater than the stated fill. It also provides safeguards to prevent underfilling below certain levels.
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The requirements placed on a packer are embodied in the following so-called three packers rules: · The actual contents of the packages produced shall be not less, on average, than the stated nominal quantity. · Not more than 2.5% of the packages may be non-standard, i.e. have negative errors larger than the Tolerable Negative Error (TNE), specified for the nominal quantity. · No package may be inadequate, i.e. have a negative error larger than twice the specified Tolerable Negative Error. In the following table of Tolerable Negative Errors: · Nominal Quantity (Qn) is the amount stated on the pack. · Negative Error is the amount below the nominal, i.e. Qn ÿ net fill. Nominal Quantity (Qn) (g or ml) From
To
5 50 50 100 100 200 200 300 300 500 500 1000 1000 10 000 10 000 15 000 Above 15 000
Tolerable Negative Error % of Qn 9 4.5 3 1.5 1
g or ml 4.5 9 15 150
Source: Information reproduced with permission from ICCS Ltd.
3.4.7 How should I deal with broken bottles in the filler? Bottle bursting within the confines of the filler is not unusual but is normally associated with carbonated products where containers are exposed to significant overpressure. Most modern fillers are well guarded but if not so protected, guarding should be provided. Guarding is also normally linked to emergency stop systems on the filling line so that any attempt to open any of the guarding results in a line stoppage. Bottle bursting can occur with either glass or PET bottles but it is glass that is of particular concern. After a bottle burst has occurred within the confines of an enclosed filler, the machinery should be stopped, guarding opened and the obvious broken glass removed. It is good practice to then remove all the bottles that were in the filler at the time the burst occurred as some may contain fragments of broken glass. This would normally be achieved by restarting the
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filler and isolating the affected bottles after they have left the filler. Operators on any filling line must be provided with appropriate personal safety equipment including eye protection and reinforced gloves for removing broken glass. Suitable bins should be provided to enable broken glass to be safely contained. Modern filling equipment is usually fitted with automatic discharge of any broken bottles and glass as well as a predetermined number of adjacent bottles. 3.4.8 How do I ensure the absence of foreign bodies in product? Reference to foreign body contamination is usually taken to infer physical contamination but it must also be remembered that contamination may also arise from both microbial and chemical origins. If products are being filled into bottles, then it is usual to subject the bottles to either a visual or an electronic inspection, or to rinsing by either water or clean air, or to both rinsing and inspection. When PET bottles are being filled, they are usually produced on a site either adjacent to the filling operation or in very close proximity to it and increasingly without intermediate storage. Storage of blown bottles increases the risk of any contamination, especially dust, but a sterile water rinse is usually sufficient to ensure complete freedom from any physical contamination. Glass bottles may present more problems, especially if they are multi-trip containers. Glass bottles, whether new or reused, should always be subject to inspection before filling, not only to ensure cleanliness and freedom from foreign objects but also to ensure that they are free from chip damage that might compromise customer safety. Other potential sources of physical contamination include wasps and other insects, cable ties and metal pieces that can become detached from equipment. Cans do not present potential problems from glass chips but they do carry the risk of other physical contamination and should be rinsed before use. Form±fill± seal packs are the least likely to suffer physical contamination but present the greatest risk from pieces of packaging materials. Risk from microbial and chemical contamination must be assessed and appropriate actions taken to minimise such risks. Microbial contamination is usually addressed by high standards of plant hygiene and product pasteurisation, whilst for chemicals the main risks are from residues of cleaning chemicals, incorrect product and rinse water. Reused bottles may be vulnerable to misuse by the consumer who may have stored almost any liquid in the container, and inline electronic `bottle sniffers' may be used to detect unacceptable residues. 3.4.9 What hygiene requirements apply to manufacturers of soft drinks and fruit juices? Apart from the more obvious considerations of customer satisfaction, commercial interests and the obligations imposed by the UK Food Safety Act 1990, all food factories are now required to comply with current food hygiene legislation.
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Producers and packers of soft drinks and fruit juices, which fall, within the UK, into the definition of `food', must meet all the relevant requirements despite the fact that these products are normally regarded as low risk. Many Food Act prosecutions that relate to quality of soft drinks and fruit juices are offences alleged against Section 14 of the Act in that the food `is not of the nature or substance or quality demanded by the purchaser'. However, such prosecutions relate to the product rather than to the premises or equipment, for which other, more recent legislation applies in the UK. In general, hygiene requires a rigorous approach to the cleaning of plant and equipment and a well-ordered and tidy factory. However, the most satisfactory way of addressing the issue is to ensure that there is in place an HACCP (Hazard Analysis Critical Control Point) evaluation for the factory that is regularly updated and embedded into the culture of the company. Adequate information is available elsewhere on HACCP systems. The selection of cleaning regimes, hygiene chemicals and their use is a key issue in ensuring compliance with appropriate hygiene standards, and specialist companies can provide valuable assistance. Other issues that need to be considered include the control of insects and vermin, compliance with environmental legislation and waste disposal, including particularly consent to discharge to sewers or watercourses, and any appropriate pollution regulation. Many producers ensure that hygiene and other obligations are met by using quality accreditation bodies to assess against appropriate ISO Standards or the BRC Technical Standard. EU Regulation 852/2004 (Implemented by the Food Hygiene Regulations (England) 2006) now makes it mandatory for food manufacturers to have a HACCP system in place as well as adequate traceability. These EU Regulations replace the UK Food Hygiene Regulations of 1995 and parts of the UK Food Safety Act 1990, although these have not been repealed.
3.5
Secondary packaging
3.5.1 How does secondary packaging affect product quality? Secondary packaging is used both for the protection of product from damage in transit and to create an image for the consumer. Pouches in particular require protection from damage but cans, cartons and bottles can also be easily damaged. The use of secondary packaging has been much reduced for reasons of both cost and environmental issues. The use of cardboard has been reduced or even completely eliminated. Cans and PET bottles are frequently only shrinkwrapped and stacked on to pallets, which are then stretch-wrapped. This is sufficient protection for transit, if handled carefully. Secondary packaging can be used for presentation purposes at the retail outlet or for forming multipacks. Cardboard wrap-around can be designed to present a premium image for multipacks.
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3.5.2 What protection is needed from secondary packaging? Secondary packaging protects transparent packs from damage by light, either by its opacity or by inclusion of a UV block which can be incorporated into transparent shrink-wrap. Care must be taken not to trap moisture inside the shrink-wrap around cans as this may lead to corrosion and to leaking cans. The major function of secondary packaging is to protect the packs from physical damage during transit. The pallets must be stacked with interlocking packs and secure stretch-wrap to ensure that the pallet does not fall apart when being moved by forklift truck or being transported. If cardboard packaging is used it may be possible to stack pallets on top of each other, possibly three or four pallets high. It is generally more economical to reduce secondary packaging and use racking for pallets.
3.6
Finished product storage
3.6.1 What are the ideal conditions for product storage? Temperature Products should be stored cool. The Arrhenius equation (see 1.6.2) predicts that the rate of chemical reactions doubles for every 10 ëC rise in temperature. Hence the rate of ageing of drinks accelerates as the temperature increases. Oxidation, browning reactions, breakdown of aspartame, etc., are all considerably reduced at low temperatures. Products should be stored as cool as possible (5±10 ëC) but obviously not cold enough to risk freezing the products. Freezing causes the drink to expand and burst the packaging. The temperature should remain constant. Large fluctuations in temperature between day and night can cause breakdown of emulsion/cloud systems and cause separation in juice drinks and fruit squashes. Microbiological spoilage is also substantially reduced or even prevented by storage at low temperature. Alicyclobacillus will grow in fruit beverages only at temperatures above 25 ëC. Light Products in clear packaging (glass or PET) should be stored in the dark, as light can accelerate oxidation and browning reactions, causing staling. Bottled waters must be stored out of sunlight, otherwise any algal spores present in the water will grow, causing the water to go green. Humidity Products must be stored in dry conditions. High humidity will encourage mould growth on paper and cardboard and cause loss of physical strength. Temperature fluctuations in humid conditions will cause condensation which can loosen or damage paper labels and cause corrosion problems on cans. Strong aromas PET is permeable. Carbon dioxide can permeate out and oxygen and volatile chemicals can permeate in. The quantity is extremely small but in a product such
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as water even minute quantities of strongly aromatic chemicals can be tasted as a taint. Cleanliness Storage conditions must be clean and insects, rodents, etc., must be absent. In conclusion, products should ideally be stored at a constant cool temperature, in dark, dry, odour-free, clean conditions. 3.6.2 What product problems can occur during storage? Extreme temperatures will cause problems for both product and packaging (see 3.6.1). Additional problems that can occur are listed below. Physical separation of oils (to the top) and particulates (to the bottom) caused by poor emulsion stability is a common problem. This can be overcome by homogenisation and/or use of better stabiliser systems. Excessive oxidation/staling during storage can be due to oxygen permeation degrading a sensitive flavour system or to initial ingress of air during production. This can be reduced by the use of flavours developed to be more oxygen resistant, by the use of antioxidant, e.g. vitamin C, or by measures to exclude air during production, e.g. gentler mixing and pumping, deaeration or the use of a nitrogen blanket. Packaging defects can result in leakage during storage. Poor lacquer coverage or seaming can cause corrosion and leakage in cans, poor blowing can result in stress cracking in PET, causing bottles to burst, and poor seam formation in cartons can cause leakage. During several weeks in storage one leaking pack can ruin a whole pallet of product. Pallets of product are at risk from physical damage in storage from forklift trucks or from being stacked on top of each other rather than in racking. Correct order of stock rotation during storage is critical. Usually referred to as FIFO (first in, first out), this ensures that the age of stock is minimised and prevents losses caused by product going out of date. 3.6.3 When do products need to be quarantined? If there is any suspicion that there is a significant fault with the product then it must be quarantined until the issue has been satisfactorily resolved. It is a legal requirement in the EU to have product traceability so that even if the product has left the factory its destination must have been recorded and its progress through the retail chain can be stopped. Quarantine may result from incorrect manufacture or processing, packaging problems or microbiological issues. Some products may be subjected to routine quarantine until acceptable microbiology results are available, i.e. a positive release system. This is commonly practised in natural mineral water and spring water bottling operations where microbiological clearance requires a minimum of 72 hours.
4 Quality issues in soft drink and fruit juice processing Abstract: This chapter lists and answers key questions relating to quality issues in soft drink and fruit juice processing. It covers ingredient quality, interactions and specifications, quality problems during manufacture, HACCP, colour and appearance changes, flavour deterioration, packaging interactions, microbiological problems and shelf-life issues. Key words: soft drinks, fruit juices, quality, ingredient specifications, HACCP, colour changes, flavour deterioration, packaging interactions, microbiological contamination, shelf-life.
4.1
Ingredient quality
4.1.1 How much deviation from ingredient specification is needed to cause a noticeable alteration in product quality? The deviation needed to produce a noticeable change in quality depends upon the contribution of the change to the ingredient and the contribution of the ingredient to the finished product. Some specifications are critical for the performance of the product. For example, the absence of pectinesterase enzyme in orange juice is critical, as pectin breakdown will cause separation of drinks and unsightly sedimentation. Some specifications are legal requirements and therefore no deviation is permissible, for example patulin in apple juice or additive levels. 4.1.2 What are the key parameters that I should evaluate to assess ingredient quality? Of most importance is that the ingredient meets the agreed specification on all parameters. This is not only the functional parameter, i.e. the level of the major
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constituent, but the level of any impurities, the microbiological status and physical parameters such as colour, particle size, etc. 4.1.3 A `floc' forms in an otherwise clear soft drink; where should I look for the likely cause? The cause of floc formation in a soft drink could be either microbiological or chemical interaction. Microbiological sediment can be evaluated by means of microscopy, plating and other techniques in order to establish the organisms responsible. The likely sources of contamination could be ingredients or packaging or the plant itself. Microbiological floc usually develops fairly slowly, unless there is gross contamination. Chemical floc is frequently caused by fruit materials. The constituents of fruit juices such as polyphenolic materials, tannins, polysaccharides, etc., can combine to form insoluble polymers which cause initially cloudiness and then floc. Mixing different clarified juices together can result in floc formation due to interaction. A clear apple juice and a clear blackcurrant juice, when mixed, may result in a hazy apple and blackcurrant drink. The inclusion of tea extract especially in the presence of fruit materials will frequently cause cloudiness and floc formation. This is due to the interaction of tannins present in tea extracts with polyphenolic materials present in fruit juices and other natural materials. A significant cause of floc formation within 24±48 hours of bottling is the presence of polysaccharides in the water supply. Polysaccharides are released into water by decaying plant material such as weeds and leaves in lakes and rivers. They are completely harmless but are insoluble in acid solutions, causing a floc in clear drinks. They are more of a problem in the autumn when leaves fall into watercourses and weeds die back. The water can be tested very simply ± add citric acid to a sample of water and leave to stand for 24 hours. If the water goes hazy then there is a polysaccharide problem. 4.1.4 When can I switch to an alternative supply source without extensive testing? When an ingredient is a very tightly specified chemical entity such as an additive (for example, citric acid or sodium benzoate) extensive testing is not necessary. A sample should be obtained and analysed to ensure that it meets all the desired compositional specifications, including microbiological and particle size specifications. Particle size distribution may be important for correct operation of dissolving equipment in the factory. It is necessary only to ensure that the material corresponds to the manufacturer's claims. 4.1.5 How do I ensure consistent product quality and avoid drift? It is essential to maintain continuity of product character over a long period. Regular consumers will notice if the product character drifts over time. The
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product must be specified as closely as possible. This is relatively simple for the easily measured parameters such as Brix, acidity, carbonation, colour, etc., but more difficult for flavour and botanical ingredients. Control must be maintained over the character of flavours and botanicals (e.g. fruit juices). A close relationship with the suppliers of these key characterising ingredients is essential. Dual supply is helpful as this permits comparison of ingredient consistency. The blending of materials from multiple supply sources also minimises any variation. Retaining deep-frozen reference samples and maintaining a trained taste panel will enable new production to be evaluated and a slow variation of flavour with time avoided. 4.1.6 How do I specify a flavour? A synthetic flavour manufactured by combination of individual flavour chemicals, i.e. manufactured to a formulation, can be readily specified as its composition is known. The specification of a flavour derived from natural botanical extracts is much more difficult to control. Botanical products vary from season to season and from location to location and a natural flavour could consist of well over 100 individual chemicals. The expertise of the flavourist is to source and blend the natural materials and extracts to maintain a consistent flavour from year to year. The specification of a flavour should include the sourcing and manufacturing details. The key flavour chemicals can be identified by means of analytical methods such as gas chromatography/mass spectrometry (GC/MS). The levels of the major contributors to flavour, together with a `fingerprint' of the chemical constituents, will assist specification. However, whilst levels of key flavouring principles can be specified, the accurate specification of flavour character is difficult and monitoring by an expert tasting panel is recommended. 4.1.7 How do I deal with variations in natural ingredients, particularly fruit juices from different sources? Fruit juices can be blended together to minimise individual differences and to obtain a consistent product. By blending together several different sources one can minimise the impact of the variations of any individual one. Orange juice, particularly from Brazil, and apple juice, from the EU, are produced in very large industrial quantities and are subject to a considerable degree of blending during production and storage. This tends to produce a more consistent product than juices produced in much smaller quantities. Juices are frequently sourced from both the northern and southern hemispheres in order to allow two purchasing opportunities per year. Buyers will attempt as far as possible to balance their purchases of juices. For example, if one source of juice is high ratio then that may be balanced by purchase of a juice which is low ratio from another source. `Ratio' is an abbreviation of Brix Acid Ratio which is a measure of sweetness in fruit juices.
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When juices are concentrated (particularly orange and apple juices) the volatile aromas are frequently collected and are restored to the juice on dilution and packing. These aromas can be used to reduce variation to some extent. When juices are being used to manufacture juice drinks the variation of the juice can be overcome by variation in the other ingredients such as flavourings, colours, citric acid, etc., and therefore variation in juice character is not such an important issue as it contributes less to the overall product.
4.2
Ingredient interactions
4.2.1 Are there any ingredients that are likely to cause unwanted interactions with others? Fortunately interactions between ingredients are not common but they do occur. Those to be aware of are as follows: · Benzoates or sorbates must be dissolved in water before addition of citric acid. The preservatives will not dissolve in acid solution. · Citric acid will cause any naturally present polysaccharides in water to flocculate. · Polyphenolic compounds present in clarified fruit juices can interact if the juices are blended, resulting in haze or sediment formation. · Tannins in tea extract will react with polyphenolics in juices to form a sediment. · Different types of caramel, e.g. E150c and E150d, are incompatible and will form a sediment if mixed. · SO2 will interact with Sunset Yellow (E110), changing the colour from orange to yellow. · SO2 can interact with anthocyanins, reducing the colour intensity. · SO2 will bind to aldehyde groups present in sugars, reducing its effectiveness as a preservative. · Ascorbic acid (vitamin C) will bleach the colour carmoisine (E122) completely. · Ascorbic acid will interact with aspartame to produce a yellow colouration. · Ascorbic acid can interact with benzoic acid under certain conditions to form benzene. 4.2.2 What are the most likely effects of ingredient interactions? As can be seen from the list in 4.2.1, ingredient interactions can have a variety of detrimental effects such as causing sedimentation, colour change or flavour changes.
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4.2.3 How are the conditions of storage likely to affect ingredient interactions? As with all reactions, ingredient interactions are likely to be accelerated by high temperatures and /or exposure to light. Interactions will be minimised by storing in cool dark conditions. 4.2.4 Can I use both benzoic and ascorbic acids in the same product? When benzoic acid and ascorbic acid are used in the same product, manufacturers must be aware of a possible interaction which can result in the formation of benzene. The mechanism is very complex and will occur only under specific conditions but all products should be checked to ascertain whether there is a potential for benzene formation. New products should be subjected to accelerated storage testing in the presence of heat and light which accelerate benzene formation (see next section below). If a product is found to demonstrate the potential for benzene formation, it is recommended that benzoic acid and ascorbic acid are not used in combination. Ascorbic acid is readily oxidised by dissolved oxygen. This reaction is catalysed by iron and copper ions and produces hydroxyl radicals, which can react with benzoic acid, converting it to benzene. Surveys conducted by several national authorities in 2006±2007 resulted in some drinks being withdrawn from the market. The FSA require that drinks containing more than 10 ppb (micrograms per litre) be withdrawn from the market; this is the WHO maximum guideline value for benzene in drinking water. Some fruits and berries naturally contain both benzoic acid and ascorbic acid (vitamin C) and levels of benzene higher than 10 g/L can occur naturally. Indeed one of the drinks in the USA withdrawn from the market by the FDA as a result of its survey contained no added benzoic acid. The benzene present was entirely derived from the fruit material. Benzene is produced by combustion and is present in the atmosphere. Surveys by national authorities have shown that an average person inhales in the region of 300 g of benzene per day, which is far in excess of any amount likely to be consumed in soft drinks. However, it is important that the formation of benzene in soft drinks be kept to an absolute minimum, and the soft drinks industry worldwide has produced guidelines (see next section). 4.2.5 What are the ICBA guidelines on benzene formation and where are they available? The International Council of Beverage Associations (ICBA) has produced guidelines for soft drinks manufacturers to minimise the potential for benzene formation. The initial step in the reaction is the formation of hydroxyl radicals from oxidation of ascorbic acid by dissolved oxygen, which is catalysed by iron and copper ions. These ions can be chelated (bound) by addition of EDTA to the soft drink. This is used in many countries, including the USA, but EDTA is not a
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permitted additive in the EU. Total removal of dissolved oxygen will also eliminate formation of hydroxyl radicals. Manufacturers of soft drinks must evaluate the potential of new products to form benzene by storing them at elevated temperature (35 ëC) and analysing them to see whether any benzene is formed. Formation of benzene is accelerated by light and heat. The ICBA `Guidance Document to Mitigate the Potential for Benzene Formation in Beverages' is available free of charge on its website www.icba-net.org in seven languages and on the BSDA website.
4.3
Ingredient specifications
4.3.1 Do I need to check every batch of ingredient against specification? It is neither possible nor desirable to check every batch of ingredients for all the specification parameters. For this reason it is important to audit suppliers and purchase only from reputable ones. Insist on certificates of analysis where particular criteria are important. The major part of ingredient quality assurance must be provided by reliable suppliers but random checking of materials must still be undertaken. For basic ingredients such as citric acid or sodium benzoate only a standard routine analysis for moisture and purity would be carried out occasionally to ensure that the agreed specification is met. It is necessary to monitor on a planned regime the commercially important parameters. For example, on a very simplistic level, powders may contain several percent moisture. This is equivalent to a several percent price increase if the specification states `<1% moisture'. For a vital ingredient such as fruit material or flavour which has a major impact upon the final product, every batch would be tested for the key parameters. A manufacturer must assess what are the essential parameters for his products and place emphasis on those. Any criteria associated with health and safety such as mycotoxins must be a priority, but it is standard practice for supply contracts to state that materials supplied meet all legal requirements. A manufacturer must conduct risk and impact assessments on all the materials purchased and decide which parameters must be monitored, in which materials and at what frequency in order to demonstrate due diligence. But however diligent, it is still possible to be caught out by the totally unexpected such as deliberate adulteration, e.g. melamine in milk. This is much more difficult to protect oneself from and vigilance by regulatory bodies and industry surveillance schemes is essential. Purchasing fruit materials from suppliers who are members of industry quality schemes, such as SGF, provides a degree of protection. 4.3.2 How meaningful are specifications for natural ingredients that may be standardised to only one or two parameters (e.g. concentrated juices)? A specification for natural materials which specifies only one or two items may be sufficient if the material is not a major contributor to the final character. For
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example, for a grape juice concentrate which is merely used for a sweetener, it may be sufficient to specify only Brix and colour. However, a juice generally needs a much more detailed specification to ensure that it will perform satisfactorily. For example, orange juice should specify at least Brix, acidity, colour, cloud stability, pulp content and absence of enzyme activity, but even these parameters are not sufficient to ensure that the juice has the right flavour character. For a key juice component it is essential to ensure the variety, ripeness and processing parameters of the fruit in order to maintain the correct flavour. When purchasing an important fruit material it is customary to obtain a prepurchase sample for evaluation and acceptance. If evaluation, including smallscale manufacture of final product and taste testing, indicates that the material is suitable then the desired quality is purchased. A portion of this original buying sample must be retained for comparison with later bulk deliveries to ensure consistency of supply. Most companies purchasing significant quantities of fruit juice would audit the processing plant during juice production to ensure the desired quality. Smaller quantities may be purchased from local juice traders who are responsible for maintaining the desired quality. 4.3.3 What are the key issues that I need to have in mind when considering specifications? You must consider the chemical, physical and microbiological parameters of ingredients which are important for product performance and cost. The chemical parameters relate to the key active principles of the material which are responsible for its characteristics. The physical parameters such as particle size could be important for handling characteristics such as flow and dissolution rates. Microbiological parameters are important for the performance of the final product. Additionally, flavour components must be included where appropriate and any legal requirements must be covered. It is common practice to include a requirement to comply with all current EU legislation in ingredient and raw material specifications. This would cover any legislative limits such as heavy metals and mycotoxins. 4.3.4 Is it possible to specify flavour character? It is possible to specify a compositional standard for a synthetic flavour which is made by blending the individual chemical constituents together. However, natural flavours and extracts are extremely complex and a single flavour may contain hundreds of individual chemical constituents. `Fingerprinting' of the flavour by means of liquid or gas chromatographic analysis can be useful to characterise a flavour, but complex natural flavours in particular are difficult to characterise. Variations in climatic conditions can affect the flavour of botanicals from season to season and supplies may be obtained from different geographical locations for commercial or availability reasons. It may be possible to specify levels of key flavour chemicals if these are known for a particular
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flavour, but taste evaluation by a trained expert panel is generally the best and most practical method. 4.3.5 How much variation should I allow in natural materials? The amount of variation that can be permitted is dependent upon the contribution of the material to the final product. It must be remembered that natural products do vary and for example, the colour of fruit juices will not be exactly the same from batch to batch. Some of this variation can be overcome by blending. In products that contain added colourings and flavourings the natural variation of the fruit is of less importance. When buying natural colours or natural flavours the blending and processing by your supplier should have eliminated natural variation and a consistent product should be purchased.
4.4
Problems during manufacture and safety issues
4.4.1 A process worker has added too much of one ingredient; how is this best dealt with? In many product mixing rooms there is today a range of automation and other ingredient control systems that should make this type of problem a thing of the past. However, many smaller manufacturers still rely on production operators dispensing their own ingredients and adding them appropriately. The overaddition of an ingredient often relates to minor components that can easily be added in excess quantity as the addition of a major item is probably more obviously noticed. In any compounding operation it is essential that operators are trained to report any error of addition as soon as it is realised. An over-addition can then often be handled by recalculating the final volume and then making the final volume of product accordingly. This may sometimes involves splitting the batch into two vessels if the revised volume exceeds that of the initial vessel. Under-addition of some ingredients may be easily corrected, although preservatives can present problems. When either sorbic or benzoic acid is used as a preservative, it is added as either its potassium or sodium salt at an early stage of mixing and before any acidic components are incorporated. Once the mixture has been acidified by the addition of fruit components or citric (or other acidulants) it will not be possible to add more of the preservative without risking precipitation of the sorbic or benzoic acid. In such a situation it may be possible to recover the batch by making an equivalent volume of product with the required over-addition of preservative. As indicated at the start of this section, there are many systems, either manual or automated, that may be incorporated to minimise the risk of incorrect additions.
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4.4.2 The final volume of a product has been exceeded; how can the situation best be resolved? In some respects this problem is the same as that covered in the previous response and may be dealt with as described there. However, depending on the amount of over-volume that has been produced (assuming the correct amount of addition of other ingredients), it is possible that the analytical values for components of the end product remain within permitted tolerances. If that is not the case then a special production batch will have to be made that is over-strength to compensate for the under-strength batch and the two combined appropriately. If the product made is for use as a syrup and thus for dilution, it is possible that the production of an over-volume syrup may be compensated for by altering the dilution ratio in a pre-mix system. The problem would be much more difficult to accommodate in a post-mix system where a `throw' of syrup is added to each bottle. 4.4.3 A batch of product has been made up but not bottled off. It is then noticed that a preservative (or other ingredient) has not been added. Can the missing ingredient simply be added to the bulk product? In the case of most minor ingredients other than preservatives the late addition of a missing ingredient can usually be accommodated. The main issue will be whether the addition causes the volume of the batch to exceed the required amount. For most minor ingredients this is unlikely to occur, but with bulk additions such as fruit preparations or sugar/syrup the late addition will invariably create a bulk of product that will exceed the target volume. In that situation reference should be made to the previous problem which deals with that situation. Preservatives are, as already indicated, a special case. The most widely used preservatives are benzoic and sorbic acids added as their sodium and potassium salts respectively. In the acidic medium of a soft drink, the salts are converted to the respective active preservatives. Both benzoic and sorbic acids have very limited solubility in water (of the order of 1500±2000 mg/L) and if the salts are added to an already acidic medium, immediate precipitation is likely to occur. It is thus very difficult to rectify the addition of missing preservatives to a batch. In the unlikely event that the missing preservative is sulphur dioxide, late addition is easily achieved either as a solution of sulphur dioxide in water or in the form of sodium metabisulphite solution. If the preservative is dimethyl dicarbonate (Velcorin) its addition always takes place after bulk manufacture by direct injection into a closed product stream. It is again essential that operators are trained to report any errors in manufacture, as in many cases it is possible to rectify potential problems prior to packaging.
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4.4.4 The electrical supply has failed during flash pasteurisation; is it necessary to repasteurise the whole batch? Electrical supply failure is now a fairly rare event in developed countries, although it can present problems in areas where the supply is by overhead distribution line. Where there is a supply failure it is more likely than not that it will affect the entire plant and not simply a single piece of equipment such as a pasteuriser. However, failure of an electrical supply to a pasteuriser will result in pumps stopping, divert valves either staying as they are set or returning to a predetermined default setting, and control systems in the pasteuriser failing. The action that is necessary will probably depend on pasteuriser design and whether the electrical failure is general, affecting all equipment in the area, or local to the pasteuriser. Flash pasteuriser design should, as far as possible, allow for the immediate diversion of product in the system to the recirculation mode in the event of failure of electrical supply or loss of temperature. If such a diversion occurs, the bulk product already pasteurised can usually be regarded as uncontaminated provided it is held in a sterile vessel. If there is a risk that unpasteurised product has reached the bulk it will usually be necessary to repasteurise the bulk. This decision will depend on the microbiological sensitivity of the product being manufactured and the probable level of initial contamination. If electrical supply is likely to be intermittent (e.g. in less developed countries) then appropriate arrangements should be made preferably to install a continuous power supply system incorporating a standby generator. The alternative would be to arrange the system to minimise product losses in the event of power failure. 4.4.5 What actions generally need to be taken during a stop in production, particularly with respect to products in the pasteuriser? Reference should also be made to the previous response dealing with the issue of electrical supply failure. However, most production stoppages occur as a result of mechanical or other problems and it is during these situations that product at risk of contamination or over-processing should be considered. Most production lines fed by a flash pasteuriser will be set up in such a way as to divert the unit into a recirculation mode if product off-take is stopped or processing temperature falls below the preset limit. This will result in a small volume of product being repeatedly pasteurised with possible flavour or colour deterioration. Depending on the plant layout, it may be possible to isolate product thus affected. Product in a tunnel pasteuriser is not likely to be adversely affected during a short stoppage that is downstream, but it is normal to set up a buffer area to allow a tunnel pasteuriser to continue operation whilst product is collected for further operations. Such a buffer storage area should be of sufficient capacity to hold the entire content of the tunnel. In a potentially long stoppage, product flow being fed to the tunnel would be stopped.
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Other critical areas that need to be considered during production stoppages are centred around product in the filler and in particular packaged but uncapped bottles or cans which are then at risk of contamination. Special procedures need to be established for stoppages in aseptic packaging lines. 4.4.6 Is an HACCP system now a legal requirement and how do I set one up? HACCP (Hazard Analysis Critical Control Point) is a system set up to evaluate the risks that arise during a food or beverage manufacturing operation and the actions that need to be taken to control and minimise or exclude those risks. The issue of whether it is a legal requirement depends upon the jurisdiction in which the beverage manufacturer operates. For European Union based companies it is now a legal requirement to operate such a system under the requirements of the European Food Hygiene Regulations (852/2004). There are many good published guides on the detailed steps to be followed in setting up an HACCP system but the general principles to be covered are as follows: · Analyse the potential hazards to the product during the course of the manufacturing or packaging operation. · Identify the points in the operation where food hazards may occur. · Decide which of the points are critical in ensuring food safety (the `critical control points'). · Identify and implement effective control and monitoring procedures at the identified critical points. · Review the analysis of food hazards, the critical control points and the control and monitoring procedures periodically and whenever the nature of the operations changes. It is normal for such a survey to be carried out by several individuals from different disciplines within the organisation and for the whole procedure to be written and updated. Whether or not the HACCP procedure is a legal requirement, it is undoubtedly a part of Good Manufacturing Practice and should be in place in beverage factories. 4.4.7 How much record keeping is required and for how long should records be kept? This response refers only to technical information and not information that is required for the purposes of accountancy or to meet other administrative and statutory demands. Normal quality assurance procedures require that sufficient records should be kept to permit full traceability of all production batches within their shelf-life and often for a similar period after the expiry of the product shelf-life. In the
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simplest terms, traceability requires a `one up/one down' approach. This means that the full history of every ingredient in a batch should be readily available, including the manufacturer's batch data and all relevant information relating to that raw material. All manufactured batch details must be readily available, including a unique batch number, date of production and expiry, relevant process control information, including operator identification, and any observations. Packaging records should also be maintained. The batch distribution details are required to enable every part of a particular batch to be traced to the immediate customer in the event of a problem arising relating to the batch and for which it could be necessary to institute a product recall. Key to this data is the ability to be able to access it within as short a time as possible but certainly within a few hours at the most. Electronic manufacturing systems will normally permit access within a matter of minutes. The retention of product formulations and formulation history is normally a matter for company policy, but most manufacturers will wish to maintain product details for an indefinite period to allow, for example, a return to a previous product. 4.4.8 What regular checks should be carried out on a tunnel pasteuriser? Tunnel pasteurisers differ fundamentally from plate or tubular pasteurisers in that the product in them is in a large number of packaged units rather than in a bulk form that is a flowing stream. In the latter types it is a straightforward matter to record process detail such as temperatures and flow rates. Within a tunnel pasteuriser the temperature of the various water sprays that are the source of heat and cooling can be monitored in the usual way but the temperature of individual closed packages cannot be measured. It is thus usual to place one or more dummy packages with time and temperature recording ability at the entrance to the unit and allow them to pass through with normal production items. Whilst the time taken for passage of packages through the unit can be easily measured, the time of passage through individual sections is essential and can be obtained with the recording devices. It is only by obtaining this information that the number of pasteurisation units (PUs) can be calculated. Care must be taken to ensure that temperatures are evenly distributed through the pasteuriser and particularly that there is no fall-off near the sides of the equipment. Dummy recording devices should thus be placed to pass through the pasteuriser at both the centre and sides of the moving bed. It is also important to monitor bottle breakage as an indicator of too high an initial temperature in the preheat section or possibly substandard bottles. All static monitoring devices should have a recording ability and it will be usual to fit audible and/or visual alarms to alert operators to changes in temperature and bed speed that are outside permitted limits.
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4.4.9 What are the main risks of contamination and how can I check for these? Foreign body contamination is one of the manufacturer's main risks and can result in expensive recalls, losses and possibly prosecution and claims for compensation. Contamination will be one of three types: microbiological, physical or chemical, in that order of likely occurrence. Microbiological contamination The risk of microbiological contamination of a product will have been assessed during its development, and the use of preservatives and/or pasteurisation decided upon. For the majority of soft drink products and fruit juices the risk of contamination by pathogens is very remote, although depending on the ingredients used the risk of previously generated toxins from certain ingredients (e.g. stored carrot juice) cannot be excluded. Despite that, microbial contamination by spoilage organisms can be very damaging and in the case of yeast contamination can cause bottles to explode with consequent risk to consumers. The risk of microbiological contamination is normally controlled by the use of a quarantine period following production of sensitive products during which a representative number of samples is examined by plating. Rapid microbiological detection techniques are now available based on the detection of microbial DNA. Such techniques can reduce the quarantine period to no more than one or two days. Physical contamination Physical contamination usually relates to the inclusion of fragments of packaging, dust or other debris, and of particular concern is the possible incorporation of glass pieces when bottles are used. Such contamination is usually detected by rinsing bottles (or other containers) prior to filling and then subjecting them to visual or automated inspection. Many manufacturers still incorporate a visual inspection of packaged and capped product as the final stage before labelling. Visual inspections, either automated or human, are of course only relevant to clear containers. For plastic packages filled in complex machinery, it is sometimes considered desirable to pass all final product through a sensitive metal detector. Chemical contamination Contamination by chemicals is by far the least likely occurrence and in many ways the most difficult to detect. The highest risk for most manufacturers is from carry-over of in-line or other cleaning chemicals; procedures, both manual and automated, should be incorporated to confirm complete removal of cleaning materials. Another risk is that of incorrect raw materials, although good syrup room procedures should prevent this. The principal residual risk is that of deliberate contamination. Syrup room and dispensary access should always be limited to those employees who have to be there to perform their job functions.
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4.5
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Colour and appearance changes
4.5.1 A normally clear product becomes cloudy on storage; what are the likely causes? When a clear product becomes cloudy on storage, there are a number of possible causes. The first issue to resolve is whether the cloudiness is due to the growth of micro-organisms. If this is the cause, the change in appearance is likely to be accompanied by changes in odour and taste. Where growth of micro-organisms is suspected, product should immediately be quarantined and tests commenced to confirm the presence and identity of a micro-organism. If micro-organisms are not the probable cause, and the product formulation contains fruit juices, another possible cause is the polymerisation of polyphenolic materials in the juice. This is most likely in red juices such as blackcurrant and raspberry where to obtain a clear product, the juices should be treated to remove materials that are likely to cause polymerisation and subsequent precipitation. If the above causes can be eliminated, cloudiness may be due to a lack of solubility of flavouring components. This is more likely to be the cause of cloudiness immediately after bottling, and frequently clarity of product returns after the product has been standing for a few days. If cloudiness persists, flavouring suppliers should be contacted to establish whether any change of raw materials has taken place. The use of essential oils, particularly of citrus origin, has often been found to cause cloudiness in an otherwise clear product. If the product is subject to filtration before bottling, filter breakdown may also be investigated, although many filtration operations are monitored by the use of turbidity meters to ensure correct operation. 4.5.2 A product displays a `ring' at its upper surface; what is this likely to be and how can it be resolved? Product ringing is normally observed only in formulations containing fruit components and then usually in products containing whole fruit (i.e. citrus comminutes). The ring is invariably composed of citrus oils, or a citrus oil-rich emulsion, that have separated either as a result of product standing for a period of time or as a consequence of either an inappropriately formulated citrus comminute or one that has not been made correctly. By reference to earlier responses (e.g. 3.2.1) it will be noted that citrus comminutes are formulated from differing proportions of the individual citrus components which are usually blended together and milled. The milling process is often carried out in a colloid mill or similar and the milling process is sometimes followed by homogenisation to ensure a stable system. If the amount of oil in the comminute is substantial (e.g. 0.3±0.5% w/w) separation becomes a significant risk and even homogenisation may not prevent subsequent separation in the end product. High oil contents are desirable to provide a strong flavour, and a balance will have to be struck between stability and taste. Oil rings will usually redisperse rapidly when the product is shaken,
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and in any product where a risk of ringing is apparent, a label instruction to the consumer to `shake the bottle' may be helpful. Rings give an unsightly appearance to the product, and in products where there is a risk of ringing, the area likely to be affected can sometimes be covered by a closure capsule. The longer-term solution is usually either to reformulate the product or comminute or to introduce a homogenisation stage into the manufacture of the end product. 4.5.3 What are the causes of product colour fading? This is one of the most frequent problems, and sources of complaint, that beverage manufacturers encounter. It is a problem that may have several possible causes, the most likely of which is exposure of the product to excessive amounts of light. It is also noteworthy that fading is normally associated with the use of added colours, either natural or artificial, rather than the intrinsic colour of a pure fruit juice. Products should be shelf tested in both south-facing and north-facing light to represent both direct sunlight exposure and the more normal daylight to assess their overall susceptibility to light. Other likely causes are the presence of ingredients such as sulphur dioxide and ascorbic acid and the initial (or subsequent) level of oxygen in the product, as colour fading appears to be linked to oxidative processes. Almost all colour fading problems are best solved by an empirical approach to determine the optimum level of ascorbic acid, which will probably be around 100 mg/litre. Strenuous efforts should be made to ensure minimal oxygen levels at bottling and the avoidance of containers that allow oxygen ingress. For products that are light sensitive, use of protective films can be of value as can wrap-round labels. Another approach is to shrink-wrap bulk packs in protective film. 4.5.4 (a) A concentrated soft drink that is normally cloudy separates into a clear upper layer and a dense lower layer of pulp; what is the likely cause and how can it be resolved? (b) A concentrated soft drink has formed a gel on storage; what is the likely cause and how can it be resolved? It is assumed at the outset that the drink has a significant fruit or juice content. Cloudy fruit or juice drinks rely for the most part on the natural cloudy components of the juice to provide a stable, evenly dispersed cloud and this in turn relies on the presence of natural citrus pectins. Pectins are, in simple terms, methyl esters of polygalacturonic acids and are susceptible to attack by various pectolytic enzymes. Degradation of the methyl ester to polygalacturonic acid or further breakdown renders the pectin component unable to support the cloudy components and an obvious separation in the juice preparation or end product can then occur. Polygalacturonic acids, produced by breakdown of pectins, are then more reactive and in particular can react with calcium ions in solution to form quite
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stable gels. Such gels can affect the appearance of end products. The two problems described are thus both linked to the breakdown of natural pectins and this is usually symptomatic of defective fruit processing. Two possible causes in the fruit processing operation are either a failure to pasteurise at a temperature at which pectic enzymes are destroyed (ca. 95 ëC) or a delay in processing before pasteurisation. Product separation and/or gel formation can generally be resolved only by referring the problem back to the raw material supplier. Stability and gel formation tests can be included in the specification and quality assessment of the fruit juice or comminute. 4.5.5 Fruit pulp forms a plug or mat on top of the product; what causes this and how should it be dealt with? The problem described above relates to products containing either cloudy juice or comminuted whole fruit and is usually a function of the pulp content of the fruit ingredient. Pulp content in a fruit ingredient is normally measured either by the amount that is held by a sieve of specified mesh size or by the depth of visible pulp that settles in a clear container in a specified period after the material has been agitated. The problem of a plug or mat of pulp settling at the top of a product usually appears when a number of factors coincide. The quantity and particle size of the pulp is often critical as is the amount of entrained air that is drawn into the end product during the mixing process. Thus larger particles are more likely to entrap air with the effect that the overall density of the pulp is reduced, causing it to rise to the top of the product. The differential density between product and pulp is crucial and it is for this reason that the problem usually occurs in dilute-to-taste products and particularly those with high carbohydrate content and a consequent high density. Bottle design can also be a significant factor, as a container with a narrow neck will magnify the effect of any low-density pulp and create a more obvious plug than would be apparent in a wide-necked container. There are a number of potential solutions to the problem: · Ensure there is in existence with the supplier a specification for pulp content in any fruit ingredient with a method of measurement mutually agreed and understood. The maximum amount of pulp that can be tolerated can then be confirmed. · Avoid entraining air into the product during the mixing process. · Evaluate the overall product in the preferred container to establish the likelihood of a plug forming. This is especially important with high carbohydrate products. · Include advice on the label for the consumer to `shake the bottle before use'. Fruit pulp plugs will usually disperse upon agitation.
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4.5.6 How can emulsion stability be best evaluated? This problem is assumed to refer to the quality assessment of a cloud and/or flavour emulsion used as an ingredient in a range of cloudy products. Emulsions used in beverages are normally of the oil-in-water type. They are manufactured by dispersing an oil such as a citrus oil (or fraction of a citrus oil) containing an emulsifying agent such as wood rosin ester or sucrose acetate isobutyrate (SAIB) into a weak aqueous solution of gum arabic. The dispersion is then subjected to emulsification in a piston-type homogeniser at high pressure. To achieve stability, more than one pass through the homogeniser may be necessary. Stability of this ingredient is normally achieved when all the dispersed oil globules are of a size less than 10 microns in diameter. Consistency of the dispersed particles can be observed under a microscope, and if the instrument is fitted with a graticule the range of sizes can also be assessed. After size measurement, there is no substitute for evaluating the emulsion in the final formulation. Products with relatively high densities will sometime cause a partial breakdown of the emulsion component because of the density differential. Considerable care should also be exercised when adding ingredients that contain alcohol or other non-aqueous components as such substances can cause a complete breakdown of emulsion. Natural emulsions obtained from, for example, citrus fruit are often significantly more stable than those made by dispersing oils into an aqueous system.
4.6
Flavour deterioration
4.6.1 What factors affect flavour deterioration? It will be evident from previous responses that the presence of oxygen, even in quite small amounts, can be very damaging to the flavour of a product. As has already been indicated, products should be protected by the use of an antioxidant such as ascorbic acid if they are likely to be at particular risk. Beyond oxygen the factors that are likely to cause flavour deterioration fall into three principal categories: physical, microbiological and chemical. Physical factors Light is probably the most damaging cause of flavour deterioration and products exposed to strong direct light will usually develop a characteristic sunstruck flavour. In most storage situations exposure to direct sunlight is minimal but even reflected light will cause deterioration, albeit at a much slower rate. The effects can be minimised by use of protective primary or secondary packaging and for most beverages light exposure is now rarely a serious problem except in unusual situations. A combination of heat with time will also have a dramatic effect on product flavour. This can best be observed where a product has been subjected to overpasteurisation and a `cooked' flavour becomes evident. Storage of product for a
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prolonged time at an average temperature in excess of 20 ëC will create a similar effect. The shelf-life of most products is determined by the time elapsed before the overall effect of time and average temperature make it unacceptable in taste. Microbiological factors In most products correctly processed, off-flavours resulting from microbiological contamination are unlikely. Their occurrence is usually the result of either incorrect processing or defective packaging. The off-flavour will frequently be accompanied by other effects such as gas production, cloudiness or obvious fungal growth. Chemical factors Leaving the possibility of contamination by, for example, cleaning chemicals, the deterioration of flavour as a result of chemical effects is usually the result of unwanted interaction between ingredient substances. It may be that some of the reactive components of a flavour have behaved in an unexpected manner or that an over-addition of a particular or incorrect component has occurred. The addition of some vitamins or minerals can sometimes have a dramatic effect on flavour. It is thus essential to be aware of the profile of a product flavour with time during its entire shelf-life to be able to identify minor variations. The presence of an off-flavour may have to be referred to a specialist laboratory for identification. 4.6.2 How is the flavour profile of a product best assessed? There are several ways in which the flavour profile of a product can be assessed. Using equipment such as a gas chromatograph (GC), the profile of volatile substances can be identified. Using various refinements such as a `sniffer device' on the outlet of the instrument it is also possible to relate the aroma of a specific peak to a perceived characteristic. However, even today it remains very difficult to relate the overall GC trace to an actual flavour profile. The most practical way in which the flavour profile of a product can be assessed remains that of using an expert flavour taste panel familiar with the product throughout its shelf-life. A typical approach would then be to place before the panel a succession of samples stored in typical warehouse conditions (e.g. ambient temperature varying between say 10 ëC and 20 ëC in dark or very low light conditions) representing the product at, say, monthly intervals throughout its anticipated shelf-life. The samples will often be tasted in comparison with a sample of the same batch as that under evaluation but stored at 0 ëC to +5 ëC in a refrigerator and/or a freshly made sample of product. In that way the panel can familiarise themselves with the way in which the product alters during its shelf-life. Some companies also make comparisons with samples on accelerated storage. It will also be useful for taste panel members to familiarise themselves with the flavour profiles of product samples exposed to abnormal conditions such as excess heat or high light levels.
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4.6.3 What kind of sensory tests can be used to evaluate flavour changes in a product? There are several publications dealing with the setting up of sensory testing of beverages, but once the facilities are set up and taste panels have been recruited there are then three main types of sensory testing in regular use: · Difference testing · Descriptive testing · Acceptance testing. Difference testing Difference testing is used when the overall objective is to determine whether a difference exists between two products or two batches of the same product. Two of the most common methods of difference testing are: · Triangle testing, e.g. AAB or ABB where A and B are the two samples. · Duo-trio testing where an identified reference sample (A) or (B) is presented with two further samples and the taster is asked to identify the different sample, e.g. (A) with A and B, or (B) with B and A. Descriptive testing Descriptive testing (often referred to as profiling) is used when a technologist requires more information about the differences in individual product attributes. The test procedures rely on the use of a trained sensory panel, which may be either internal or external, with members able to recognise all product attributes and then score them objectively on a scale of the experimenter's choice. This type of test is particularly useful in providing both numerical and descriptive (vocabulary) assessments of products during their shelf-life. Consumer acceptance testing Almost all shelf-life tests include some form of acceptance testing or hedonic ranking of samples, as ultimately the shelf-life should be set at the point just before the sensory attributes of a product change sufficiently to decrease the product appeal. Panels for this work often include untrained personnel and consumers and the results are more subjective than in other types of test. Types of acceptance testing include the paired preference test and the nine-point hedonic scale. 4.6.4 Apart from the obvious source (i.e. the flavouring), which ingredients are most likely to cause flavour problems? Unwanted flavours or flavour taints in a product can arise from almost any ingredient. If a product is found to have an unwanted flavour taint immediately after manufacture, it may be necessary to carry out a laboratory investigation such as dissolving each single ingredient in water to see whether the taint is present. Water itself can of course be a source of flavour taints and the most
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likely characteristic is probably an excessive amount of residual chlorine. Chlorine, apart from having its own characteristic taste, can also react with other components such as fruit materials to produce a disinfectant note which probably arises from very small amounts of chlorophenolic materials. Water for beverage manufacture should at least be treated by passing it through an active carbon filter. Other potential flavour taints can arise from excessive additions of almost any ingredient or from materials that have been stored adjacent to odoriferous materials during transit or in a warehouse. The development of a flavour taint during storage is usually more difficult to identify and may result from unwanted interactions between minor ingredients such as vitamin or mineral additions, excessive heating during pasteurisation, storage in unduly warm conditions or microbial contamination. In order to identify unusual taints, it is important for laboratory staff to be familiar with the taste of products for which they are responsible during the full range of storage periods and conditions. An unusual taint occurring regularly during storage will usually require a series of tests to be arranged to eliminate one or more suspect ingredients and assess the results during accelerated storage. 4.6.5 Where can I get help in determining the likely origin of an unusual flavour taint? As already referred to in the previous response, it is important for laboratory staff to build up taste experience of the normal range of flavour characteristics that can develop during the range of normal storage conditions to which the product is likely to be exposed. Such staff will then be well placed to determine what is an unusual flavour characteristic. Flavour taints that arise immediately after manufacture are best dealt with by a process of elimination (i.e. each ingredient in turn being dissolved in process water to try to identify the taint source) and are usually within the range of ability of most beverage laboratories. When the source of a taint is then identified it would be normal for the problem to be referred back to the ingredient manufacturer for enquiry and reporting back. Taints arising during the life of the product may require the services of a specialist laboratory (of which there are several in the United Kingdom) to identify the nature of the taint from which it may be possible to identify possible sources. Probably the most likely source of taint arising during product life is from microbiological contamination. This may be very obvious if it is accompanied by carbon dioxide production or changes in appearance of the product. In such circumstances, the identification of the contaminating micro-organism and its subsequent elimination is sufficient to remove the problem. Some beverage control laboratories may be capable of such work but if not there are external microbiological laboratories to which the work can be contracted.
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4.6.6 How important is the removal of chlorine in process water in avoiding flavour defects? Reference has already been made to this problem in 4.6.4. Chlorine residues will both cause direct flavour defects and interact with some ingredients to produce other taints that often have very low flavour thresholds. It is thus important that chlorine is removed from process water. Beverage manufacturing operations that use town water supplies will invariably receive water containing some residual chlorine, although the levels can be very variable depending on a number of factors. Where a private borehole or other water supply is used within a manufacturing operation chlorine may or may not be added by the beverage manufacturer, for sterilisation purposes, depending on the quality of the borehole water. Where there is any possibility of process water containing chlorine it should be treated by passing it through an active carbon filter to remove chlorine. An important issue to remember, however, is that once water has been treated for removal of chlorine it is then vulnerable to reinfection and growth of microorganisms and ideally should not be stored in bulk beyond the chlorine removal stage. Following chlorine removal, the risk of microbial contamination reaching a product can be effectively minimised by the use of ultraviolet irradiation as near to the point of use as possible. It is important that carbon filters and ultraviolet irradiation equipment should be maintained and service in accordance with the manufacturer's recommendations. 4.6.7 How can packaging influence flavour deterioration? In general, packaging of beverages is unlikely to have any direct effect on the product it contains, although there have been exceptions. For example, beverages packed in cans may in some circumstances pick up metal from the can, although this is now rare. If a product containing sulphur dioxide should find its way into a can, interaction between the metal in the can and the SO2 can produce the very unpleasant smell of hydrogen sulphide. Similarly, it has been known for bland products such as bottled water to pick up taints from plastic bottles. A particular example in the past has been the pick-up of acetaldehyde by water packaged in green PET bottles. The most likely effect that packaging will have on product contained within it now relates to the ability of the package to exclude oxygen and/or light. Most plastics used to contain beverages will permit some oxygen transfer from the external atmosphere to the product, although currently the use of PET probably gives the best compromise between strength and durability, cost and oxygen transfer rate. Glass bottles, cans and laminated packages such as Tetrapaks or Combiblocs provide very good protection from oxygen ingress to a product. The damaging effect of light on the flavour of a product has been discussed earlier and it is important that the packaging should provide as much protection as possible. Glass and plastic bottles will usually allow light into a product, and to minimise possible flavour (and colour) deterioration it may be necessary to
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utilise wrap-round labels or coloured sleeving or to provide protection with secondary packaging. 4.6.8 What kind of flavour deterioration can arise from microbiological infections? Soft drinks and fruit juices are vulnerable to infection by a wide range of microorganisms but particularly yeasts and moulds, and a more limited range of bacteria. When a product becomes infected by yeast there is normally a very characteristic aroma and flavour associated together, in many cases, with carbon dioxide gas production. Less common yeasts will have their own characteristic metabolites that have their own aroma. Products infected by moulds will often have a typical musty aroma, but a typical feature of mould infection is likely to be the presence of sediments and strands of fungal material. If a product becomes infected by bacteria the flavour and aroma effects may be more difficult to characterise. For example, infection by a species of Lactobacillus will often generate lactic acid and thus affect the sweetness/acid balance of the product but have relatively little impact on the aroma. Less common is the infection of beverages containing small amounts of alcohol (e.g. from flavourings) by Acetobacter species and the consequent production of acetic acid and its characteristic vinegary smell. Any suspected contamination of a product by micro-organisms should normally start by examining the product for the organism rather than by trying to identify the unknown aroma. In some circumstances identification of the microorganism may rely on the identification of the aroma substances but the usual priority is removal of the contaminant.
4.7
Packaging interactions
4.7.1 What problems are most likely to arise when plastic packaging of any kind is used? Plastic is very inert and presents little concern when used for packing drinks. All plastic must comply with the EU Materials in Contact with Foods Regulations, 2002/72/EC and subsequent amendments. These regulations lay down standards for leaching of contaminants from the plastic under specified test conditions. They apply to both virgin and recycled plastic. Plastic suffers from several problems mainly associated with its permeability and low melting temperature: · It is permeable to oxygen and CO2, which places limitations on shelf-life. · Low levels of acetaldehyde are produced during the manufacturing process for PET and can taint water bottled in PET unless a low-acetaldehyde PET is specified. · Heavy PET bottles (>100 g per two-litre bottle) can be used in a returnable manner. This is not done in the UK but is practised in some EU countries.
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However, PET will absorb flavours, requiring sniffers to be used to avoid cross-contamination. Hot detergent must be used only with care to wash PET as this will soften and shrink the plastic. · Drinks cannot satisfactorily be pasteurised in-bottle in plastic bottles due to the softening of the plastic. However, it is possible to hot fill specially designed PET, though at a relatively low temperature (ca. 75 ëC). · Because inert plastic will absorb hydrophobic flavours to some extent, it may be necessary to use a slightly higher level of flavour usage compared to glass to allow for this. 4.7.2 When cans are used, what are the most likely interactions? Cans are made from either aluminium or iron (steel) and are lined with an epoxy lacquer to prevent contact between the drink and the metal can, but microscopic flaws do occasionally occur. Soft drinks and fruit juices have a low pH and are fairly aggressive to the metal, which they will slowly dissolve, eventually causing `pin-holing' and consequent leakage. The presence of even very low levels of SO2 (more than 5 mg/L) can increase this interaction considerably, and sulphited juices should not be used as ingredients in drinks filled into metal cans. Water packed into steel cans may dissolve very low levels of iron. If this water is poured into whisky it may produce a blue colour due to a complex formed between the iron and polyphenolic compounds in the whisky. This can be prevented by the addition of a low level of sodium phosphate to the water. 4.7.3 What special problems, other than physical contamination, are possible if glass packaging is used? Glass is an excellent material into which soft drinks may be packed. It is inert, impermeable and transparent. However, a significant proportion of glass is recycled in the form of `cullet' added into the molten glass from which the bottles are blown. Care must be taken to ensure that the glass recycled is free from contamination, particularly metal contamination, for example lead from refractive glass. The purity of the glass must be monitored by the bottle manufacturers. Products packed in glass may be subject to light damage if stored in light conditions in clear shrink-wrap. This can be overcome by the use of light barrier film. Glass is also subject to physical damage, which can be hazardous. This is especially true for carbonated products. A carbonation level of 4 volumes (ca. 8 g/L) generates an internal pressure of 64 psi at 25 ëC. If a glass bottle is damaged by physical impact the glass pieces flying about can cause injury, particularly to the eyes. The problems of flying glass caused by a carbonated glass bottle bursting can be reduced by minimising the headspace and eliminated by using a complete plastic sleeve label. Glass bottles may be weakened by manufacturing flaws and by `scuffing'. Scuffing is the surface scratching caused by bottles rubbing together during the
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filling operation and general handling of returnable bottles. Much of the strength of a glass bottle is lost by surface damage and bottles with excessive scuffing must be rejected. Glass bottles are frequently sprayed with a lubricant immediately after manufacture in order to reduce the risk of scuffing. This is known as `cold end' treatment. This may cause microbiological problems if any of the spray enters the bottles. 4.7.4 What issues are likely to arise when flexible packaging is used? Pouches are the lowest-cost form of drinks packaging but they have been slow to gain acceptance by the consumer. They are, of course, only suitable for still drinks and are considered by many consumers to be awkward to use. They remain a niche market. Like the other form of flexible packaging, laminated cartons, pouches have only low intrinsic strength and must be packed into substantial secondary packaging for distribution. Full pallets will bear only a little top load and therefore it is strongly recommended that full racking systems are used and that in order to minimise damage full pallets are not stacked on top of each other. 4.7.5 Do aseptic packs have any particular problems associated with them? Aseptic packing is the process of filling and sealing a sterile product into sterile packaging in a sterile environment. Hence maintaining sterility is critical to aseptic filling. The plant must be thoroughly cleaned and sterilised before production can start, and if production stops and the plant has to be opened due to an internal problem then the sterilisation must be repeated. This can lead to a lot of downtime on the production line. Products filled aseptically have no preservatives added and therefore any spoilage organisms, even at extremely low levels, will tend to lead to a problem. In addition to aseptic cartons, which have been popular for many years, there has been a growth in the production of aseptically filled bottles. These require a high degree of hygienic production and transportation of all packaging materials so as to minimise risk of contamination by spoilage organisms. The bottling line must be enclosed and the plant sterilised, usually by hydrogen peroxide or peracetic acid. The use of sterilisation procedures and positive over-pressure using sterile filtered air requires much more technical control and monitoring than a standard bottling line. The monitoring of microbiological status is also more critical than for a normal bottling line. This leads to both a higher initial capital cost for an aseptic line and higher running costs. 4.7.6 How much attention should I pay to the specification of packaging material? The detailed specification of packaging material is absolutely essential. The behaviour and handling characteristics of packaging on a production line can be
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seriously affected by apparently insignificant specification changes. Even changing the colour of a cap can affect how it handles when being applied to a bottle. This is because the pigments included in order to add colour can slightly alter the mechanical properties of the plastic. Any changes to packaging specifications should be subjected to a factory production trial as it is difficult to predict what the impact may be and serious reduction in production efficiency could result. 4.7.7 What are the major packaging problems? The areas of a bottling operation where most packaging problems occur are associated with labelling and capping operations. These can have a major impact on the efficiency of a production operation, the appearance of the product and consumer complaints. Reel-fed plastic labels are much more reliable and can increase line efficiencies by as much as 20% compared to the use of paper labels. The high-speed application of caps at the correct torque and with successful operation of the tamper evidence device is a complex operation and can be subject to a degree of failure. Focusing on correct label and cap application will greatly improve overall performance and is also important for consumer acceptance of the product. Glass bottles are susceptible to contamination from broken glass. This may arise from bottles bursting during filling or from accidental breakage elsewhere. Tiny fragments of broken glass can be transferred by contact with crates, boxes or pallets and contaminate other packaging. Pieces of glass in drinks containers are such a serious issue that it is essential that any broken glass in equipment or on the floor is thoroughly cleaned up immediately to prevent crosscontamination. The major problems with can filling are incorrect seaming, resulting in leakage, and excessive moisture in shrink-wrapped trays, causing stress corrosion. The other major problem to which cans are susceptible is damage in transit, as cans are very fragile and easily dented. A significant cause of problems is the instability of stacked pallets during distribution. It is vital that packs are adequately interlocked and that a minimum of space is present between pallets. If necessary, adhesive should be used between packs. The packs should cover the whole pallet area, otherwise movement is possible and the stacked pallets will tend to lean and possibly topple over due to the lorry stopping and starting during distribution. If the stacks are leaning the retailer will probably refuse to unload the lorry and return it to the factory or depot. Stretch-wrapping of pallets in the recommended manner with adequate overlap of film and applied at the correct tension will also alleviate problems of damaged pallets during distribution.
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4.7.8 Why are product shelf-lives shorter in PET packages when compared with glass, cans or TetraPak/Combibloc? PET is more permeable to oxygen than glass, cans or cartons. This results in a faster rate of oxidation/staling of drinks. PET is transparent to light which will also accelerate the deterioration of product flavour compared to cans and cartons. In the case of carbonated drinks, PET is permeable to CO2 which limits the shelf-life, especially in small bottle sizes. For a two-litre bottle, loss of carbonation of less than 15% in 90 days is generally considered to be acceptable. The shorter shelf-life for smaller bottles is because as the bottle size reduces the ratio of surface area to volume (and hence rate of carbonation loss) increases. Glass and metal cans are totally impermeable to CO2 and will retain the desired carbonation levels almost indefinitely. However, the loss of carbonation limits the shelf-life of carbonated drinks in two-litre PET bottles to nine months and that of 250 ml PET bottles to around 2±3 months. Carbonation loss can be reduced by coating the PET bottles with a barrier plastic such as PVDC. This will, however, result in the bottles being non-recyclable, which is not desirable. Carbon dioxide permeability is obviously not an issue for laminated cartons as they are unsuitable for carbonation. Laminated cartons are constructed from layers of cardboard, polyethylene and aluminium. The polyethylene forms a liquid barrier on the inside, the aluminium provides a barrier to oxygen, and the board provides an outer printable covering. The improved barrier to oxygen and light enables a longer shelf-life to be obtained for sensitive products compared to a standard PET bottle. For example, orange juice will be acceptable in cartons for up to a year but for a maximum of six months in hot filled PET bottles. 4.7.9 What is the best plastic in which to pack still drinks? The meaning of the word `best' in this case depends upon the primary parameter being considered. Which is the primary concern ± quality, shelf-life or cost? There are many types of plastic available and `best' is a compromise between physical strength, appearance, barrier properties, cost and availability. Three types of plastic are used for packaging drinks ± polyolefins (polyethylene or polypropylene), polyvinyl chloride (PVC) and polyethylene terephthalate (PET). Polyethylene naphthalate (PEN) has been proposed as an alternative to PET but has not become a commercial success chiefly due to its high cost. PET exhibits excellent clarity and in a skilfully designed bottle can be difficult to distinguish from glass merely by appearance. This clarity allows the consumer to view the product. Unfortunately PET is more expensive than other commonly used plastics but it is often used for premium and long shelf-life drinks. Polyethylene (usually in the form of high density polyethylene, HDPE) and polypropylene are used for short shelf-life products, usually through the cold chain. They are low priced but are opaque and have less consumer appeal than PET. Polyethylene and polypropylene are injection moulded and can be
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produced in more complex shapes than PET; for example, integral handles can be included. Polyvinyl chloride (PVC) was formerly widely used for drink packaging but due to environmental concerns and the use of phthalate plasticisers, which have received very adverse media coverage, PVC is rarely, if ever, used nowadays.
4.8
Microbiological problems
4.8.1 What makes one soft drink more susceptible to microbiological spoilage than another? Spoilage organisms require the correct conditions and nutrients in order to be able to grow and multiply, and different soft drinks vary in their ability to support growth. Note that not all growth of organisms results in product spoilage. For example, bottled natural mineral water contains a microflora but it is not harmful and growth is limited by the lack of nutrients. Carbonation inhibits the growth of aerobic organisms, particularly moulds, and a low pH also inhibits many organisms. Cola can be manufactured without the need for pasteurisation or preservation (provided that the usual hygiene standards are observed). It has a low pH (ca. 2.5), a high carbonation and low levels of nutrients. These conditions are sufficient to inhibit the low levels of organisms present in a hygienic bottling operation. However, a carbonated fruit drink will be much more susceptible to spoilage as the fruit provides ample nutrients and the pH will tend to be slightly higher (ca. 3.5). Fruit drinks must therefore be pasteurised or preserved (usually both). Juice drinks are susceptible to fermentation by yeasts, and uncarbonated (still) juice drinks are susceptible to mould growth. The growth of spoilage organisms can be inhibited by addition of benzoic acid or sorbic acid, up to the limits prescribed by legislation. EU regulations permit a maximum of 150 mg/L benzoic acid and 300 mg/L sorbic acid to be used. If a mixture is used, the maximum level of sorbic acid is 250 mg/L. For certain drinks sulphur dioxide is also permitted. Concentrated fruit cordials (squashes) may contain up to 250 mg/L SO2 (350 mg/L if barley is used) and drinks containing more than 235 g/L of glucose may contain up to 50 mg/L SO2. Note that benzoic and sorbic acids inhibit the growth of spoilage organisms. They will not protect products against serious microbiological contamination and they are of only limited effect against some strains of organisms. Preservatives are not a guarantee against spoilage; they merely make a product more resistant to low levels of organisms. 4.8.2 What are the organisms that I need to be particularly aware of? The spoilage organisms of concern are yeast, moulds and bacteria, specifically acetic and lactic bacteria. Yeasts, e.g. Saccharomyces cerevisiae, may cause
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fermentation, i.e. generation of CO2 resulting in pressure build-up in the container. This is particularly dangerous in glass bottles which may explode and potentially result in serious injury. Some yeasts, however, e.g. Brettanomyces, will grow slowly in the drink, causing off-flavours. Growth of bacteria, e.g. Acetobacter, will cause deterioration of the flavour of the drinks. Some organisms causing specific problems of which manufacturers should be aware are: · Zygosaccharomyces bailii ± see 4.8.10. · Alicyclobacillus acidoterrestris ± found in fruit materials due to soil contamination. It is a thermophile and will survive even extreme pasteurisation conditions, resulting in the development of smoky/medicinal off-notes in juice products. · Penicillium roquefortii ± a mould which occurs very commonly in the atmosphere. It will not grow in carbonated drinks but has been a serious problem for still drinks preserved with sorbic acid. It will metabolise sorbic acid to 1,3-pentadiene which has an extremely pungent unpleasant aroma. Several other Penicillium moulds will also cause this problem. Whilst these organisms will cause spoilage of the products, rendering them totally unpalatable to drink, they should not normally cause harm to anyone consuming them. They are spoilage organisms, not pathogens (see next section). 4.8.3 Can soft drinks become contaminated with pathogenic organisms? If normal hygienic precautions are taken in the supply chain and in factory operations then pathogens should not get into soft drinks. The low pH of soft drinks (<4) will prevent growth of most pathogens, and pathogens are very susceptible to heat. Even moderate pasteurisation will destroy them. Therefore the risk of pathogens in soft drinks is low. The major risk is from a contaminated water supply. If the water supply to the bottling factory is not reliable then a treatment plant capable of producing potable water must be installed. Most pathogens in water will be destroyed by chlorination at several mg/L for a few minutes' contact time. The chlorine must then be removed by means of a carbon filter to avoid tainting the drinks. Cryptosporidium, which can occur in water supplies, is resistant to chlorine but can be removed by microfiltration or reverse osmosis (RO). There have been instances of illness due to contamination of unpasteurised fruit juices with salmonella. This can arise from serious malpractice such as using windfall apples from orchards in which animals have been pastured to manufacture unpasteurised apple juice. In the UK, the FSA has issued on its website guidelines covering workers in the food and drink industries suffering from illness. This particularly relates to workers who have suffered from sickness and diarrhoea. They should not be allowed into food handling areas for at least 48 hours after symptoms have ceased. Some food and drink companies will not allow visitors on site if they have suffered from sickness or diarrhoea within the previous 48 hours.
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Water bottling companies must be particularly vigilant as water can be a good carrier for pathogens. 4.8.4 What are the early signs of microbial contamination? Microbiological contamination frequently becomes noticeable due to formation of a haze in an otherwise clear product. It may also form a fine sediment. In a naturally cloudy product microbiological contamination may become apparent due to `off-flavours' caused by the organisms. In extreme cases moulds or fermentation may become apparent. Most soft drinks are not sterile but contain very low levels of organisms which will cause no problems during the shelf-life of the product. This is sometimes referred to as `commercially sterile'. The presence of preservatives will inhibit the growth of low levels of spoilage organisms. 4.8.5 How do I find the likely source of microbial contamination in a product? Tracking down the source of microbiological contamination (infection) can be extremely difficult and time-consuming, especially if the level of infection is very low and intermittent. It usually helps to identify the exact strain of organism which is causing the problem. For example, many strains of Alicyclobacillus may be found in fruit products but only one (Alicyclobacillus acidoterrestris) causes an unpleasant off-flavour on storage. Specialist laboratories will identify unknown organisms on a commercial basis. The most common causes of infection are natural ingredients, particularly fruit materials. If a particular ingredient is suspected of being responsible for a problem, the complaint samples should be checked against production records to establish whether the problem is associated with a particular raw material batch or supplier. Alternatively a different supply of raw material could be used for a period of time to establish whether there is any effect on the problem. Packaging materials and the bottling plant itself are other frequent sources of microbiological problems. Packaging materials, bottles and caps should be tested for levels of contamination. Cardboard is a notorious source of mould spores and should be avoided if possible. Care should be taken to ensure that rinse water does not become contaminated, otherwise packaging can have higher levels of contamination after rinsing than it had before. The bottling plant can harbour organisms which will infect products manufactured on it. It is essential that all the plant is adequately sanitised and that no hidden spots are missed by the routine cleaning programme. It is possible for organisms to develop resistance to cleaning regimes and sanitisers and changing these periodically is advisable to avoid build-up of resistant organisms. The plant should be checked for sterility after sanitising by swabbing sites of potential contamination such as seals, gaskets, valves, etc. A frequently overlooked source of contamination is the air supply. Any compressed air used for operating bottling equipment must be clean and pipelines
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should be sanitised and, where necessary, sterile filters fitted (and maintained). Sterile air filters are also sometimes used on air intakes into product tanks in order that only sterile air enters the tanks as product is pumped out. Water supplies should also be checked but it is unlikely that the spoilage organisms would be waterborne if a reliable town supply is being used. On-site water treatment plant and filters should also be checked. As previously mentioned, for very low intermittent infection it can be extremely difficult to identify the source, but it is often due to the plant. Manufacturers sometimes resort to total cleaning of the bottling line, that is, they take it apart, clean and sanitise the individual pieces and reassemble the line, replacing all the seals and gaskets and swabbing to check for sterility. 4.8.6 What value does a period of quarantine storage have? Quarantine storage is used to isolate stock and prevent its distribution and sale whilst the degree and seriousness of a problem is assessed. For a mechanical problem, for instance faulty cap application, or for an intermittent packaging or labelling problem the stock would be quarantined, manually inspected, and any unsatisfactory stock discarded. In the case of a suspected fault with a pasteuriser, possibly resulting in insufficient pasteurisation, the quarantined stock would be evaluated microbiologically by statistical sampling. The stock would then be discarded or sent for sale depending upon the test results. Microbiological tests usually take three or four days to complete if samples have to be plated and incubated. The quarantine period is required in order to prevent product getting onto the market until it has been fully evaluated and approved. 4.8.7 How can I best ensure that the water I use does not become a source of contamination? Water used for rinsing packaging is recycled in order to minimise water usage for cost and environmental reasons. It is essential to ensure that the water is clean and does not become a source of contamination. The equipment manufacture responsible for installation of the packaging handling would normally also install suitable rinse water treatment plant. It is customary to have a cleaning and disinfection process in place. This would typically consist of a fine filtration system and ozonation. The water quality must be checked regularly for cleanliness and ozone level. How regularly will be learned by experience. Cans and bottles are sterile at the point of production because of the nature of their high-temperature manufacturing process. Provided they are quickly and cleanly sealed into pallets the levels of contamination should be very low. This is even more true when bottles are blown on site for immediate use and many large plants now have a can manufacturing factory alongside. There is an increasing trend to air blow the cans and bottles rather than use water. The air removes any particles which may be in the pack. This may be assisted by ionisation of the air.
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4.8.8 An equipment breakdown causes a delay of several hours before a product can be packed off; does this situation pose a serious threat to the microbiological condition of the product? The degree of microbiological risk will depend upon the type of product and the conditions under which it is being held and packed. Each situation must be evaluated individually in the light of experience with the plant and products. If the product is being held in clean cold conditions and then subjected to pasteurisation, a delay of several hours may not matter. If it is possible to chill the product whilst it is being held, this will help. Products that are pasteurised during packing, either by flash pasteurisation or by in-pack pasteurisation, are at less risk. The temperature of the pasteurisation could be increased by a few degrees to increase the heat input with minimal flavour impact. For a clear product microfiltration of a sample may be used to obtain a rapid microbiological assessment. A decision must be made whether to fill the product or to dispose of it. If it is decided to pack the product then the stock should be quarantined until final microbiological results are available. 4.8.9 Why is mould contamination not a problem for carbonated drinks? Moulds are aerobic and require oxygen in order to grow. They cannot grow in the atmosphere of carbon dioxide and the very low oxygen levels found in carbonated drinks. 4.8.10 What is Zygosaccharomyces bailii and why is it such a problem? Zygosaccharomyces bailii is a wild yeast which can occasionally be found in some imported fruit juice products, particularly tropical juices. It is a very serious problem because it is resistant to both benzoic and sorbic acid preservatives, which are the only ones permitted by the EU in juice drinks. This means that even the presence of extremely low levels of Z. bailii contamination will result in serious spoilage problems. It can be very difficult to eradicate from a contaminated production line. 4.8.11 I know that most product spoilage results from yeast and/or mould contamination; what bacterial infections might affect soft drinks? There is a very broad range of organisms classified as bacteria. Some are pathogens, i.e. cause illness in humans, though most are harmless. A few will grow in soft drinks, causing spoilage. The three principal groups of bacteria that can cause spoilage problems in soft drinks are acetic acid bacteria, lactic acid bacteria and Acinetobacteria. They are capable of growth at the low pH found in soft drinks and will result in the development of off-flavours making the drink unpalatable.
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4.9
Shelf-life issues
4.9.1 What are the main factors affecting the shelf-life of a product? The most important factor determining the shelf-life of a soft drink or fruit juice is its microbiological condition. For the majority of products, especially those pasteurised by one means or another, the product will not suffer microbiological deterioration during an indefinite shelf-life. However, for fruit juices sold as freshly squeezed for which no pasteurisation has been used, the shelf-life will be limited to a few days, depending upon the temperature of storage. The other vulnerable products are those juices that have been freshly squeezed but have received only a light pasteurisation and have not been packaged aseptically. In such cases shelf-life can be up to about 12±15 weeks provided that products are packaged in a clean environment and stored chilled (i.e. at 0±5 ëC). For sealed products where the risk of microbial deterioration is practically non-existent there are three main factors affecting shelf-life: the oxygen level in the product, exposure to light, and the temperature at which the product is stored. Oxygen levels can be minimised at packing by appropriate flushing of containers by inert gas, and subsequent oxygen ingress through the packaging is determined by the packaging used. Glass cans and laminated board packs will very effectively prevent oxygen ingress in most cases, and plastic containers vary in the amount of oxygen they will admit to the product. To minimise the amount of light, products should be packed in containers that do not allow light to pass. For clear containers such as glass that have many other benefits, light ingress may be minimised by appropriate use of secondary packaging or wrap-round labels. Heat damage to products can be reduced by storage in cool conditions. For most products, however, normal UK warehouse conditions will permit an adequate shelf-life, although high-level racking may submit products to excessive conditions during summer months. Products stored in countries with a tropical climate will benefit from being stored at a maximum of around 20 ëC. 4.9.2 Can the shelf-life of a product be accurately predicted? See 1.6.1. 4.9.3 What does the term `shelf-life' of a product actually mean? From the retailer's and consumer's perspective, the term is normally used to refer to the `best before' date, i.e. the latest date on which the product is said by the manufacturer to be in an acceptable condition for consumption. The term `best before' should not be confused with `use by', which is normally employed for products that carry a risk of microbiological deterioration or contamination. Shelf-life should apply to expected typical rather than idealised storage conditions, and some possibility of adverse storage conditions should be explored by the manufacturer and built into the period declared.
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There will always be situations where products are not stored ideally and complaints may arise. However, to provide the consumer with the best possible advice the product label should be used to indicate specific storage needs. For example, `store in a refrigerator after opening' or `keep away from light' could be incorporated into a label. There may often be a tension in determining the `best before' date between the sales force who want the longest possible shelf-life and the quality and technical personnel who may wish to take a more cautious approach. In practice the shelf-life is often finally determined by commercial considerations such as the time taken to get the product onto retailers' shelves and the minimum life acceptable to the retailer. 4.9.4 Should the shelf-life of products be monitored on a regular basis? If so, how should this be done? It is useful to carry out regular monitoring of product shelf-life as a means of ensuring that product reaching the consumer is of the required quality. Even when the product at manufacture is of the required standard, small changes in raw material and packaging quality that may not be picked up on quality control checks can affect shelf-life. All products should in any event be tasted for acceptability at production. The only satisfactory means of achieving this is to take regular (case) samples from production on, say, a monthly basis and keep them within a typical warehouse environment as being representative of the way in which product reaching the trade will be handled. Samples may then be withdrawn from each case throughout the stated shelf-life and submitted to an experienced taste panel using a relevant test to assess acceptability. The question of what is an appropriate reference standard against which products are to be tasted will be taken locally. It may be considered that the latest fresh acceptable batch should be used or that samples from each case could be held refrigerated and used as references. 4.9.5 Why do products need a long shelf-life and how can this be maximised? There is invariably a tension between the quality team who want products to be of the best possible quality in all circumstances and the marketing staff who want the longest possible shelf-life. The length of a product shelf-life, particularly in relation to that of relevant competitor products, may affect the decision of a retailer about whether the product should be stocked at all. Most retailers will set a minimum percentage of a product's shelf-life that must be available when it enters their system. Individual manufacturers will then wish to examine their storage and distribution chain to establish both the minimum and typical times that products take to reach retailers' shelves. It will then be possible to evaluate the
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opportunity for supply. Typical shelf-lives for fruit juices will be from a few days in cold-chain distribution and sale to around a year for long-life products. Similarly, most soft drinks will be sold with around a 12-month shelf-life. Particular care needs to be taken with products that carry a claim, especially for a specific vitamin, as the claim must be sustainable throughout the shelf-life of the product. Such products require careful formulation with sufficient overage of the vitamin to ensure claim compliance at the end of shelf-life. For mineral claims it will be normal practice to add a slight overage of, say, 5%. Leaving aside the issue of claim compliance, which usually requires a shelflife to be limited, shelf-life can often be maximised by careful selection of primary and secondary packaging. There will invariably be a trade-off between the cost of packaging and increasing shelf-life. 4.9.6 How does packaging affect shelf-life? It will be clear from some of the other responses in this volume that the main factors that cause deterioration in fruit juices and soft drinks, assuming correct processing to remove microbial problems, are the presence of oxygen, the effect of light, and excessive temperatures. Thus the greater protection that can be provided by packaging to prevent oxygen ingress and minimise the effects of light, the longer the shelf-life is likely to be. Oxygen in the product at the time of filling the container should be minimised, for example by ensuring that water or juice used is stripped of any oxygen if necessary and by gas (usually nitrogen) flushing of the container immediately before filling, and possibly also by using an oxygen scavenger such as ascorbic acid in the formulation. Selection of the appropriate container will then be the only route by which oxygen can enter the product. Glass, metal and board laminates offer the best protection against oxygen ingress whilst plastic containers have a variable performance in terms of oxygen transfer rates. Protection against light is best achieved by using opaque containers, coloured bottles or film and effective secondary packaging such as labels. For minimising the effects of excessive temperature, clear guidance needs to be issued to those in the distribution chain about how and where to store products before they reach the consumer and, if necessary, advice needs to be given to the consumer on the product label itself.
5 Bottled waters Abstract: This chapter lists and answers key questions relating to the manufacture of bottled waters. It covers UK legislation, water extraction, water treatment and bottling, quality issues, storage and distribution. Key words: bottled waters, mineral water extraction, mineral water treatment, mineral water bottling.
5.1
Legislation
5.1.1 What UK legislation applies to bottled waters? The word `bottled' is defined in the regulations as including any form of packaging, therefore drinking water in cans, cartons, etc. is covered by the bottled waters regulations. Bottled waters are subject to EU legislation, the primary one being Directive 2009/54/EC, together with its subsequent amendments. These are transcribed into UK legislation as the Natural Mineral Water, Spring Water and Bottled Drinking Water (England) Regulations 2007, SI 2875. Parallel legislation exists for Scotland, Wales and Northern Ireland: Scotland 2007 SI 435, Wales 2007 SI 3165 (W 276) and Northern Ireland 2007 SR 420. Additionally the Food Standards Agency (FSA) has written extensive guidance notes for these regulations which can be found on their website. The regulations should be read with reference to the guidance notes. At the time of writing the EU Commission has published guidance to regulate the removal/reduction of fluoride in natural mineral water (NMW) using activated alumina and is drafting guidance on the use of `greensand'-type filters for the removal/reduction of unstable elements. In addition to the `vertical' legislation which is specific to bottled waters, the more general EU and UK food hygiene and labelling legislation is also applicable, e.g. the Food Labelling Regulations 1996, the Food Safety Act 1990, the Food Hygiene Regulations 2004, the Nutrition & Health Claims Regulations
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2006, and the Materials in Contact with Food Regulations 2007. Bottled waters are subject to all the legislation covering food production, manufacture, packaging, etc., unless specifically excluded by the vertical regulations covering bottled waters. 5.1.2 What are the differences between natural mineral water, spring water and table water? Natural mineral water (NMW) NMW sources in the United Kingdom must be `recognised' by the local authorities and listed by the FSA on their website. All NMWs within the EU are listed on the EU website. The guidance notes published by the FSA include a very useful section describing the type of information and data necessary for a water to obtain recognition. The water must be from a protected underground source and be free from pollution. The composition of the water must be constant, i.e. free from any surface influence. The composition and temperature of the water should be monitored for a sufficiently long period to ensure that it is not subject to surface influence. This is normally considered to be two years. NMWs are not subject to compositional requirements in the same way as mains drinking water or spring or table waters. Historically NMWs were often high in naturally occurring minerals or had unusual mineral compositions and were consumed for their supposed health-giving properties. Today, however, many NMWs, especially in the UK, have a relatively low mineral content. Since NMWs are not covered by compositional requirements, it is mandatory to quantitatively declare the characterising mineral ions on the label. Limits on undesirable constituents are laid down in EU Directive 2009/54/EC. At the time of writing provisions are being made to permit reduction of fluoride by means of adsorption on activated alumina. Spring water Spring water must be derived from a single defined underground source but is not subject to the recognition procedure required by NMW and does not have to be of constant composition. However, spring water must meet the chemical and microbiological standards laid down in the regulations. These are closely based upon the standards for mains drinking water. In some EU countries treatment of spring water is prohibited, but in the UK treatments that do not alter the essential character of the water are permitted, e.g. UV irradiation or membrane filtration. Table water The name has no legal status but has become a customary name in the UK for bottled drinking water that is neither NMW nor spring water. Like spring water, it must meet the parameters specified by the regulations, but there is no limitation as to its source nor the treatments to which it may be subjected. Some
Bottled waters 119 `table waters' are highly purified by a process such as reverse osmosis (RO) and then the desired mineral salts are added in the quantities required. The water may be ozonated immediately prior to filling to ensure that it is sterile in the bottle. Such highly purified and sterilised waters are at the opposite end of the spectrum from the totally untreated natural mineral waters. Note that in the UK any drinking water that has been subjected to a softening or desalination process must have a minimum restoration to 60 mg/L calcium hardness. 5.1.3 How should different waters be labelled? The labelling requirements for NMW are closely prescribed by the regulations. In addition to the standard labelling such as contents, best before date, etc., NMW must display the name and location of the source and the quantity of the characterising minerals. This is usually in the following format: Typical analysis
mg/L
Calcium Magnesium Potassium Sodium Chloride Bicarbonate Sulphate Nitrate
62.3 15.6 1.1 10.5 29.8 32.1 8.4 6.4
Dry residue at 180 ëC pH at source
220 6.8
NMW that contains carbon dioxide must be described using one of the three descriptions prescribed in the legislation as follows: · Naturally carbonated natural mineral water · Natural mineral water fortified with gas from the spring · Carbonated natural mineral water. For spring water the listing of its characterising mineral constituents is optional but the label must state the name and location of the source. The name and labelling of the water must not imply anything that is not true. For example, a water could not be called `Mountain Spring' or show pictures of mountains on the label unless it was sourced and bottled in a mountainous area. There are no special labelling requirements for table water over and above the normal requirements for foodstuffs.
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5.1.4 What licences are required to extract and bottle water? The abstraction of water from aquifers is subject to local regulation and full approval must be obtained from the relevant authorities prior to any work being undertaken. In the UK detailed maps of the underground mineral structure are held by the Geological Survey from which information can be obtained on the probability of finding commercial quantities of underground water. In England and Wales the Environment Agency (EA) is responsible for maintaining the sustainability and quality of aquifers. The EA issues abstraction licences and operates catchment area management systems (CAMS) to maintain the balance between abstractions and replenishment in compliance with the EU Habitats Directive, 92/43/EC. In Scotland abstraction licences are issued by the Scottish Environmental Protection Agency (SEPA). Note that in some parts of England aquifers are under stress due to unsustainable abstraction rates resulting in the lowering of water tables, and in these areas no new abstraction licences are being issued and reductions are being made to existing ones. It is the long-term intention of the EA that all abstraction licences should be renewable on a 12yearly cycle. Bottled waters are classified as food products and in accordance with the EU Hygiene Regulation (852/2004) water bottling plants must be registered with and approved by the appropriate authority (Environmental Health Office) as food production facilities. NMW and spring water must be bottled at source and therefore planning permission is required for construction of a borehole and factory. 5.1.5 What testing regime do I need to put in place? Prior to starting production from a new source it must be rigorously tested for any possible contaminants, both chemical and microbiological. Parameters are listed in the regulations and include a large range of possible pollutants, including pesticides. The water should be tested for residues of all pesticides that might have been used in the catchment area. All pathogens and parasites must be totally absent. It is essential to establish that the source is capable of maintaining the desired abstraction rate without detriment to the quality of the water. The source should be pumped at the maximum rate until the aquifer reaches equilibrium and the water retested. The source must be confirmed as being of reliable quality before any production commences. Once it has been established to the satisfaction of the relevant authorities that the water quality is acceptable, production can begin. The minimum sampling regime for spring waters is laid down in EU Directive 98/83/EC and is based upon the rate of production. Production should be operated on a positive release system, i.e. batches of water receive analytical and microbiological clearance prior to distribution. It is not possible to analyse every possible parameter on a continuous production basis but indicator parameters must be monitored. These include taste, aroma, turbidity, colour, pH, conductivity and TVC at 22 ëC and 37 ëC. Any changes to these parameters outside their normal range must be
Bottled waters 121 urgently investigated as these could be a sign of intrusion of water from another location into the aquifer with the risk of contamination. It is essential to monitor a new source very intensively. As more information is gathered about the performance of the source over time more confidence is acquired and the intervals between major analytical monitoring may be extended (within the legal limits). Though no specific time period is stated in the legislation, it is customary to monitor a source for at least two years prior to applying for recognition of a natural mineral water. If the compositional parameters of the water are constant throughout two years, summer and winter, this indicates that the aquifer is not subject to surface effects. It is advisable to monitor water both at source and in bottle. If any problem becomes apparent it is essential to know whether it is arising from the source or from the bottling operation. It is a legal requirement (Hygiene Regulations 852/ 2004) to establish and maintain an HACCP system to identify and monitor the critical control points in the bottling process. In line with the regulations, the FSA has produced a series of industry guides, including the Industry Guide to Good Hygiene Practice: Bottled Water Guide published by Chadwick House in 2001, ISBN:1 9043 0631 4. At the time of writing the guide is being reviewed and will be published by The Stationery Office. 5.1.6 Do I need any discharge consents if I am only bottling water? Yes: as the operator of a registered food manufacturing site you must agree discharge consents with the relevant authorities even though you will be discharging primarily water. There will be some discharges in addition to water and these must be taken into account. It is common practice to keep pumping a source (at a low rate) even when no bottling is taking place. Manufacturers find it advantageous to maintain some flow from the source at all times rather than operate in a stop/start manner. This water is discharged to waste. In some cases a soak-away can be used. 5.1.7 What other ingredients can I add to bottled waters? The only ingredient permitted to be added to NMW or spring water by the bottled water regulations is carbon dioxide. The addition of any other ingredient moves the water into the soft drink category. However, the position of added flavour is somewhat grey and waters containing only a very small quantity of flavouring are sometimes regarded as being in the water category. For example, water and waters containing only flavouring are (at the time of writing) exempted from the EU's nutrition labelling requirement in the draft Food Information Regulations. Mineral salts may be added to bottled drinking water (table water) provided that they are declared in the ingredients list in the normal way. Note that under the UK Bottled Waters Regulations 2007 any bottled water that has been softened or desalinated must contain a minimum of 60 mg/L calcium hardness.
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Natural mineral waters and spring waters can be used as an ingredient to manufacture soft drinks, but the final products will be classified as soft drinks, not waters.
5.2
Water extraction
5.2.1 How much information do I need about my borehole and how much water can I extract? Many beverage plants have their own borehole and the presence of a borehole was often a reason for the siting of a plant. In other instances boreholes are sunk to meet the specific needs of a bottling or packing operation. The basic information needed for any borehole relates to the quality and quantity of water that it can provide. The quality of water is perhaps the overriding issue and ideally it should meet the quality required for drinking water as given in EU Directive 98/83/EC. However, if the water is or is to become a source of natural mineral water, the quality parameters do not necessarily need to comply with the directive, provided the water is free from contaminants of either a chemical or a microbiological nature and is not in any way harmful. Water for manufacturing or drinking that is not of natural mineral water status may be treated to bring it within the parameters of the directive. Beyond the information about basic water quality and quantity it is always helpful to know the depth of the well and the nature of the terrain into which it has been sunk, and ideally a drill log should be available. The amount of water that may be drawn from a borehole depends on what the borehole will actually deliver ± the borehole yield ± and the amount stated in the abstraction licence. The borehole yield is a short-term measure of how much water can be extracted from a specific well at a steady state of drawdown of the water level. At this point the amount being extracted is just equal to the rate of replenishment. Longer-term considerations will also need to be taken into account and these are often determined by the authority issuing the licence for extraction. Abstraction licences in the United Kingdom will give an overall permissible volume to be extracted as well as a maximum extraction rate. They are currently renewable every 12 years. 5.2.2 How does my borehole need to be protected? This response assumes that the water catchment area is suitably protected and only deals with the actual borehole itself. Many older boreholes or wells consist simply of a submersible pump and its connecting pipework sunk into a hole in the ground. This arrangement can allow debris from the ground to drop down and potentially contaminate the water or block the pump inlet. The best practice is now to sink a casing into the borehole from ground to water level and to grout at least the upper part of the casing with sulphate-resistant concrete, thus sealing any gap between the casing and the surrounding soil. The casing should be of
Bottled waters 123 water-quality material and a stainless steel pipe would be the ideal. The casing must be of a diameter suitable to allow the removal of the submersible pump and associated pipework. Headworks of the borehole then represent the most likely point of entry of any contaminant and the borehole casing should terminate above ground level by at least 30±50 cm in a chamber sealed by an appropriate cover that has a locked access. In this way surface flooding of the borehole can be minimised and unauthorised access denied to prevent any interference. Depending on the location of the borehole, further works may be necessary. For example, if located in a field it will need to be fenced to prevent animal interference, and if in a factory site it may be necessary to protect the headworks from possible vehicle or other damage. Each site should be assessed for likely hazards and appropriate protection provided to minimise any other risk of contamination or interruption of water supply. It may be considered desirable in some situations to install an alarm to indicate attempted access to the borehole. 5.2.3 How close to the source do I need to bottle? The only statutory restrictions on where bottling takes place in relation to the source relates to water designated as natural mineral water or spring water where regulations require it to be `bottled at source'. However, that expression appears capable of different interpretations as, provided the water is transferred by an unbroken pipeline, there are many examples of natural mineral water being bottled several kilometres away from the actual point of extraction. The key issue for any water bottling operation is the avoidance or at least the minimisation of points where the water is at risk of contamination of any kind. As an example, some organisations transfer water by road tanker from the point of extraction to the bottling location. This operation carries the risk of contamination during the transfer into and out of the tank or the risk of contamination as the result of foreign materials in the tanker. In practice, the proximity of the bottling location to the source will usually be driven by what is economic and technically feasible and carries the lowest risk of possible contamination of the water. 5.2.4 How can I establish whether the water from my borehole is of consistent quality? To be able to use a particular source it will need formal approval by the competent authority (in England and Wales the local Environmental Health Office) and this will require a full analysis that will identify possible risk areas. The subsequent consistency of water quality is important in giving assurance to the user that the source is not likely to suddenly become contaminated by surface storm water, effluents or other undesirable material. Correct design and management of the borehole will go a long way towards giving that assurance but beyond that regular analyses are essential.
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A full analysis of the parameters listed in the EU water quality directive (98/ 83/EC) is time-consuming and expensive and is only likely to be carried out occasionally, but evaluation of a smaller number of selected parameters should be carried out on a regular basis. One parameter that can be measured on-line as a very useful indicator of gross water quality is conductivity. This measure is crudely representative of the total mineralisation of the water and will quickly indicate any gross changes. Depending on the hydrological nature of the water, a selection of key parameters can be identified that will easily demonstrate seasonal changes. Provided the water is of potable quality, it will be of particular importance to assess bacterial quality regularly and to measure levels of nitrates, which for some water sources can change quickly. There may also be other specific parameters that should be examined on a regular basis. 5.2.5 What action should be taken if the quality of water from a borehole suddenly drops? The underlying assumption is that the user of the borehole is aware of a typical range of variance for the key parameters of the quality of the water extracted and that a sudden change indicates a significant move outside the usual range. Any action will be driven to a large extent by the nature of the change identified. In general, a significant change in water quality may indicate a possible contamination of the source, and a detailed evaluation of the structure of the borehole and associated headworks should be undertaken. The nature of change may give clues. For example, a sudden increase in nitrate nitrogen may indicate a substantial use of fertiliser by a local farmer. An increase in iron or zinc levels could be associated with increasing corrosion of pipework. The sudden presence of bacterial indicators of faecal contamination coupled with an increase in ammoniacal nitrogen is almost certainly associated with contamination by sewage effluent. Any sudden change should trigger a series of analytical measurements to establish whether the change is simply a `blip' or part of a trend. It may be desirable to consult a water quality expert for an opinion on the likely cause of the change in quality. Most important, however, is the need for vigilance to ensure continued safety of the water for human consumption. 5.2.6 Can extraction from a borehole be intermittent? The most consistent quality of water from a borehole is achieved when water is extracted continuously or at least regularly. There are particular risks that may be associated with intermittent extractions if the water is to be used for direct consumption or for use as the major component in a beverage. Perhaps the most obvious risk of intermittent use is the possibility that the water quality may have changed since the last period of extraction. The risk of such an occurrence can be related to the hydrological nature of the borehole. For example, a borehole
Bottled waters 125 deep into a chalk stratum is very unlikely to have become contaminated whereas a borehole in ground that may be fissured could become contaminated by flood water. Pumps and fittings not used for some time may become corroded and give rise to raised levels of metal ions. Another problem of intermittent use is that water may surge back down the borehole when a pump is stopped and create an erosion chamber. When the pump is restarted, debris may be carried back into surface tanks and vessels. The risk of this occurring can be minimised by fitting non-return valves on the delivery pipes. If it becomes necessary to use a borehole intermittently, water should be pumped to waste for a period of time. The situation and nature of the borehole and the time elapsed since its last use will determine whether additional analyses should be carried out before reuse of the water is started.
5.3
Water treatment and bottling
5.3.1 What treatments can I apply to different water sources? The treatments permitted for NMW are extremely restricted. Filtration is permitted but no treatments that alter the microbiological status. Aeration or oxygenation followed by filtration or decantation is permitted for the removal of unstable elements, e.g. iron, manganese or sulphur. EU Directive 2003/40/EC permits the use of ozonated air for the removal of arsenic, provided that prior approval is obtained from the appropriate authorities. Reduction of fluoride in NMW by means of activated alumina is permitted by a temporary EU Commission guideline, which will be published as a Directive in due course. Commission guidelines on the use of `greensand'-type filters for the removal of iron, manganese and arsenic are also being developed at the time of writing. No provision is made in the EU legislation for treatment of spring waters and the subject is left to national legislation. In the UK there is no specific legislation, except that use of ozonated air is prohibited unless for the specific purpose of arsenic removal. Treatments are allowed provided that they do not alter the intrinsic characteristics of the water, for example UV irradiation or membrane filtration. However, if the spring water were subjected to significant treatment which altered the intrinsic character, such as softening, it could be argued that the consumer was being misled as he would not expect a spring water to have been so treated. In some EU countries, e.g. France, treatment of spring waters is limited to those allowed for NMW. There is no restriction on the use of treatments for bottled drinking water provided that the water is rendered fit to drink and compliant with all the parameters laid down in the regulations. Water can be totally demineralised by reverse osmosis or deionisation and then remineralised with the desired salts. Ozone can be added immediately prior to bottling, ensuring that the packaged water is sterile.
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5.3.2 Can I bottle water and soft drinks in the same plant? It is preferable to bottle water on a dedicated line. Water acquires taints extremely easily and very rigorous cleaning followed by complete removal of any traces of cleaning agents is essential prior to the bottling of water if soft drinks have previously been bottled. Water is also susceptible to microbiological contamination, particularly by moulds. This could be a problem, especially if drinks containing fruit juices are being run on the line. The cleaning process will inevitably result in considerable downtime and there will be increased risk to product quality, but if proper care is taken it is possible to produce water and soft drinks on the same line. 5.3.3 What is the best way to sterilise a water bottling plant? Water is not sterile; it has a microflora and it is essential to prevent the build-up of biofilms in the plant by a regime of regular cleaning/sterilisation. A water plant can be sterilised by either chemical or physical (heat) means. The use of steam (or water at >85 ëC) is very effective but it is essential to ensure that all parts of the plant reach a sufficiently high temperature. Many plants do not have a large steam supply and it is more common practice to use chemical sterilisation. There are several chemical cleaning/sterilisation agents that can be purchased from industrial suppliers. Quaternary ammonium salts and similar cleaning agents are effective but can be difficult to completely eliminate from the plant. Hypochlorite is commonly used as a sterilising agent and is very effective. Concern has been expressed over possible production of chlorinated hydrocarbons as a result of the action of chlorine on biofilms. The water should be monitored when production resumes to ensure that such byproducts of sterilisation are absent. Ozone is possibly the most commonly used sterilising agent for water bottling plants. It is produced by electric discharge in air and dissolved into the water stream. It is a potent sterilising agent and has the advantage that it breaks down to oxygen, thereby requiring no flushing of the plant. It is very toxic and precautions to prevent breathing the vapour must be taken. It is also very corrosive to organic materials such as seals which may be used in the plant. It is essential to ensure that the plant is suitable for ozone sterilisation prior to its use. Organisms can develop resistance to sterilising agents. If monitoring shows a steady increase in the level of microflora in the plant, it can be useful to use a different sterilising agent for a period of time. 5.3.4 Do I need to take any special precautions in a water bottling plant? All the procedures necessary in a soft drinks plant must be taken, plus greater hygiene requirements and greater emphasis on the avoidance of taints. Particular precautions include the following: · Filling must be done in a clean environment to prevent any ingress of organisms, e.g. algae or mould spores, from the atmosphere. Employees suffering from any illness must not be allowed into the filling area, etc.
Bottled waters 127 · Higher grade PET bottles and higher grade caps are often used for water bottles than for soft drink bottles to avoid the possibility of taints, which are far more apparent in water than in flavoured drinks. · Higher grade seals are frequently used in water bottling equipment, also to avoid taints. Great care must be taken to prevent any possible contamination from the surface gaining access to the source. It must be sealed and the area around it protected. The caps used on bottled waters must legally be tamper evident.
5.4
Quality issues
5.4.1 What are the most likely appearance defects affecting bottled waters? Packaged water needs to be crystal clear at all times as even if not packed in clear glass or plastic containers the consumer expects to see a product of exceptional clarity when the product is decanted. Probably the most likely visual defect is the appearance of cloudiness or sediment. Such problems can arise if there is a breakdown of a filter in the packaging system or if particles are present that are too small to be removed by the filter. This defect sometimes occurs if water surges in the underground chamber from which it is pumped. It is useful to install a visual inspection point in the line where any haziness may be observed, although there are many electronic in-line turbidity meters that will perform this function continuously and sound an alarm or divert water if a problem arises. Other visual defects that can occur during storage of bottled water are a cloudiness caused by growth of large numbers of bacteria (which need not necessarily be harmful to the consumer) or algal growth that causes a green appearance to the insides of the container. Packaged water should not be exposed unnecessarily to strong light, as this is the principal cause of algal growth, and if there is a significant bacterial count in the source of water for bottling it should be subjected at least to UV irradiation and possibly chlorine treatment and removal before bottling (not applicable to natural mineral water or spring water). 5.4.2 What are the most likely sources of taints in bottled waters? Natural mineral waters may not be treated other than by filtration to remove sediments. Any taints that arise in such water should arise only from the source or by contamination from the packaging. There is, however, the risk that unless fail-safe cleaning systems are used, possible cross-contamination from cleaning chemicals may occur. Some natural mineral waters have a slight sulphurous taste and the taste that is characteristic of their mineral content. There have been occasions when plastic packaging has given rise to taints and a specific problem has occurred when acetaldehyde has been leached from green PET bottles to impart its characteristic taste.
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For waters that are not subject to the constraints of natural mineral water or spring water, the taint most likely to occur is that of chlorine either from the water source or because it has been used to sterilise the water and removal has not been complete. The presence of chlorine can sometimes create a taint that is characteristic of `disinfectant' as a result of interaction with components of different plastics. The same potential sources of taints from acetaldehyde and cleaning chemicals still apply. 5.4.3 What kind of organisms will grow in bottled waters? Many bottled waters have a microbial content unless they have been subjected to UV irradiation immediately before packaging, although all bottled waters must be free from pathogenic organisms. The absence of pathogenic organisms is a legal requirement for natural mineral and spring waters as a condition of their recognition, as is the absence of other pathogenic organisms such as the parasites Giardia and Cryptosporidium. Other potential pathogens such as Pseudomonas aeruginosa should also be absent. All packaged waters must be free from pathogenic organisms after bottling. Many bottled waters, however, do contain a wide spectrum of bacteria of naturally occurring bacteria of environmental origin, the numbers of which may fluctuate widely after packaging. Bacteria will consume all the dissolved assimilable organic carbon and their numbers will grow until all the available nutrients have been consumed, when numbers then fall. It is not unusual for counts of 105 to 106 colony forming units (CFU) per millilitre (ml) to be found several weeks after bottling. There is little or no risk of contamination of water by yeasts, although moulds will grow. Algal growth can sometimes cause problems as indicated in a previous response. 5.4.4 Does the carbon dioxide added to bottled waters need to be of special quality? Contaminants in the carbon dioxide added to water to produce sparkling bottled water have in the past been the reason for major product recalls. The problem that has occurred on at least two separate occasions was caused by the presence of the carcinogenic hydrocarbon, benzene. As a result of such problems, the European Industrial Gases Association (EIGA) working with the Compressed Gases Association of America (CGA) and the International Society of Beverage Technologists (ISBT) has prepared a specification for liquid carbon dioxide for use in foods and beverages. This is shown in the following table which shows component specifications for carbon dioxide (CGA/EIGA limiting characteristics):
Bottled waters 129 Component1
Concentration
Assay Moisture Acidity Ammonia Oxygen Oxides of nitrogen (NO/NO2) Non-volatile residue (particulates) Non-volatile organic residue (oil and grease) Phosphine2 Total volatile hydrocarbons (calculated as methane) Acetaldehyde Benzene Carbon monoxide Methanol Hydrogen cyanide3 Total sulphur (as sulphur)4 Taste and odour in water
99.9% v/v min. 50 ppm v/v max. (20 ppm w/w max.) To pass JECFA test 2.5 ppm v/v max. 30 ppm v/v max. 2.5 ppm v/v max. each 10 ppm v/v max. 5 ppm w/w max. 0.3 ppm v/v 50 ppm v/v max. of which 20 ppm v/v max. non-methane hydrocarbons 0.2 ppm v/v max. 0.02 ppm v/v max. 10 ppm v/v max. 10 ppm v/v max. <0.5 ppm v/v max. 0.1 ppm v/v max. No foreign taste or odour
1. Carbon dioxide is obtained from a number of sources including combustion of hydrocarbons, wells and geothermal sources, fermentation, hydrogen and ammonia manufacture, limestone rocks, coal gasification, acid neutralisation and ethylene processes. Depending on the process it will be prudent to add other specific components that may arise from these processes. 2. Analysis only necessary for carbon dioxide from phosphate rock sources. 3. Analysis only necessary for carbon dioxide from coal gasification sources. 4. If the total sulphur content exceeds 0.1 ppm v/v as sulphur then the species must be determined separately and the following limits applied: · Carbonyl sulphide 0.1 ppm v/v max. · Hydrogen sulphide 0.1 ppm v/v max. · Sulphur dioxide 1.0 ppm v/v max.
5.4.5 What shelf-life can be expected from bottled waters? Assuming there is no gross contamination of a packaged water by microorganisms its shelf-life in terms of physico-chemical characteristics can be regarded as more or less indefinite. However, bottled waters do suffer from the effects of light and oxygen ingress which can produce stale taste characteristics. If the water is carbonated there will be a steady loss of carbon dioxide, the rate of which will vary depending on the type of packaging and closure. In practice most water bottlers will apply a similar shelf-life as a best before date as they do to soft drinks. For most products this is 12 months, although to meet specific market needs there are unlikely to be difficulties in increasing this to 18 months
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for non-carbonated products. Products that are considered to have a shelf-life (durability) in excess of three years do not need to be marked with a best before date in the United Kingdom. 5.4.6 Do I need special closures or packaging for bottled waters? As a general statement, closures that are used for bottled soft drinks are suitable for bottled waters. However, it should be remembered that as bottled waters (not including so-called flavoured waters which are legally soft drinks) do not contain any added ingredients (other than carbon dioxide for carbonated products), they may be particularly susceptible to any taints that may be leached out from bottles or caps. Mention has been made of past difficulties when greencoloured PET has been used for packaging water. Any acetaldehyde or indeed any other component that leaches from the bottle will have an immediate effect on the flavour of the water that possibly would not be apparent in a flavoured product. Certain types of cap liners have also been known to create taints because of the type or amount of plasticiser used in the material employed to form the cap, and all material should be shelf tested for compatibility with the product in typical storage conditions. So-called sports caps are increasingly popular with consumers as they allow easy access to the product without having to unscrew a cap. Sports caps should be checked for seal integrity to reduce the risk of water leaking out or ingress of contaminants. For carbonated products, bottles and caps should ensure that the retention of carbon dioxide is satisfactory. Many bottled waters are carbonated to a value that may be higher than for soft drinks and retention of the gas, both before and after opening, will be an important factor in consumer satisfaction. It is now a legal requirement in the United Kingdom for closures to be tamper evident.
5.5
Storage and distribution
5.5.1 Do bottled waters require any special storage conditions? As a general principle, bottled waters can be satisfactorily stored prior to retail sale in similar conditions to soft drinks and fruit juices. The appropriate conditions are in a clean dry warehouse, typically out of direct light, and preferably in darkness, and in temperatures at or below about 20 ëC. It is particularly important to avoid strong light as this may trigger the growth of chlorophytes, a simple form of algae, which can give the product a green appearance. Although chlorophytes are thought to be of no significance to human health, their appearance can discourage consumers. They increase the content of organic material in water, which can act as a food source for bacteria. The increase in bacterial growth can also impart a taste taint to the water. Manufacturers may also feel it is appropriate to advise consumers about storage after opening. Large bottles of non-carbonated water should ideally be
Bottled waters 131 resealed and stored under refrigerated conditions to minimise the growth of any bacteria that have entered the product as a consequence of opening the bottle. Large bottles of carbonated water must be resealed to minimise the loss of carbon dioxide. Storage under refrigerated conditions is also desirable for carbonated water as it is likely to minimise the loss of gas. Smaller bottles that may be regarded as single servings are not likely to require any consumer storage information. If it becomes necessary to store products in higher ambient temperatures, it may be necessary to reduce the shelf-life for carbonated products as in-bottle pressures are directly related to temperature. Higher internal pressures are almost certain to lead to a more rapid loss of gas.
6 Packaging, storage and distribution of soft drinks and fruit juices Abstract: This chapter lists and answers key questions relating to the packaging, storage and distribution of soft drinks and fruit juices. It covers packaging selection, defects, problems during filling and packaging operations, post-filling defects, storage conditions and distribution problems. Key words: soft drinks, fruit juices, packaging, distribution.
6.1
Selection of packaging
6.1.1 What factors should be taken into account when the selection of packaging is under consideration for a new product? Two factors must be taken into account: · Packaging type and design for consumer appeal · Technical performance. Both are critical to any new product. Some decisions are obvious, for example carbonation rules out use of cartons, pouches and PVC. Only cans and glass or PET bottles can be used for carbonates. Market positioning and image are key considerations. A premium adult product for sale primarily in HORECA would be sold in a fancy glass bottle rather than a cardboard carton. Products are frequently packed in different formats for different market sectors. Some formats have become almost `traditional' in consumer perception, for example the one-litre carton for long-life fruit juice, the gable top for onelitre short-life (chilled) fruit juice, the two-litre PET bottle for standard carbonate in grocery, etc. Cans are frequently used for the impulse sector when resealability is not important. The choice between steel and aluminium is made
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on commercial grounds as technically they are equally good. In the UK 330 ml and 500 ml PET bottles have provided stiff competition for cans in recent years. 6.1.2 How do I evaluate the likely performance of different types of plastic packaging? What factors should I consider? The types of plastic used for soft drinks containers are: · · · · · · ·
Polyethylene terephthalate (PET) Polyvinyl chloride (PVC) High density polyethylene (HDPE) Polycarbonate Polylactic acid (PLA) Polyethylene naphthalate (PEN) Polystyrene.
When deciding which plastic to use, it is important to consider carbonation, appearance, strength and cost. By far the most widely used is PET and for carbonated drinks it is currently the only commercially viable option. For other plastics the loss of CO2 is too rapid or they are too expensive. PET offers good CO2 retention. However, as the size of the bottle decreases, the ratio of surface area to volume increases, resulting in a more rapid decrease in carbonation level. For bottles of less than 330 ml the loss of carbonation results in a seriously shortened shelf-life. Optimisation of bottle blowing to improve uniformity of wall thickness and molecular orientation of the PET has allowed reductions in the weight of PET bottles whilst minimising reduction in performance. A typical twolitre PET bottle now weighs only 38 g and bottles of only 34 g are being tested. Being permeable, PET not only allows CO2 to escape but oxygen to enter. Products which are very sensitive to oxidation may require protection by incorporation of antioxidants (e.g. ascorbic acid) or a reduced shelf-life. Coating PET with a barrier plastic such as polyvinyl dichloride (PVDC) can increase shelf-life by a factor of 2 or 3, but prevents the PET from being recycled. Topgrade PET has an appearance almost comparable to glass in clarity and small, good quality PET bottles can be difficult to distinguish from glass just by sight. Environmental issues are becoming increasingly important and this has contributed to the decline of PVC. Also PVC does not exhibit the clarity of glass or PET. Its CO2 retention is too low to permit use for carbonates, though it has been used for water and squashes. HDPE has poor gas barrier properties but can be used for still products with a short shelf-life. It has good physical strength but poor transparency. Polycarbonate is expensive but has good transparency and rigidity. It is frequently used for large (18 litre) water bottles used on office water coolers but can go brittle and crack. PEN has been proposed as an alternative to PET but has not proved commercially viable. Polystyrene is used, often as part of a laminate in the packaging of cup drinks. Plastics derived from corn starch ± polylactic acid (PLA) ± are available but have yet to make a significant impact on the market. One drawback is that PLA
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is difficult to separate from PET in recycling plants and the presence of very small quantities has a seriously detrimental effect on the quality of recycled PET. Also, most PLA is not compostable in a domestic situation and requires industrial-scale digesters for biodegradation. It is currently expensive and tends to be brittle and hence prone to physical damage. 6.1.3 What do I need to look out for when selecting the closure? The closure is one of the most unappreciated pieces of modern technology. Closures must be manufactured to very tight tolerances and applied with a high degree of precision in order to work satisfactorily. They are really pieces of high technology and can be a major source of problems if not given the degree of attention they deserve. The international specifications database is held by the Closure Manufacturers Association and can be found at www.closuremanufacturers.org. The types of screw closures in common usage are plastic, aluminium and rollon. Aluminium closures with tamper-evident bands are not recommended due to the possibility of the tamper-evident band causing laceration of the palm of the hand during the opening procedure. Roll-on closures are applied as an aluminium sleeve over the top of the filled bottle, and the thread and seal are made in situ by application of a set of rollers (hence the name). Roll-on closures are used on still products such as squashes and cordials. Plastic caps are the most commonly used and are available in a variety of forms. They may be one-piece or fitted with a separate liner. The cap can be a significant source of CO2 loss during storage and caps may have a PET liner to reduce this and provide a better seal. Note that the seal is not made by the threads of the bottle/cap but by the top inner surface of the cap pressing against the top rim of the bottle. The threads must be capable of holding the cap securely in place but without requiring excessive force (torque) for removal. BSDA recommends that caps up to 28 mm diameter should require a torque of less than 17 lb/in for removal and caps from 28 to 38 mm diameter less than 25 lb/in. It is usual to employ a lubricant to assist cap removal. In addition to screw caps, bottles may be sealed by means of metal crowns which are crimped on to the bottle top. These are traditionally used on glass bottles for the licensed trade but not elsewhere. They require an opener for removal, though some may alternatively be unscrewed. There are a variety of different standards for both alcoholic and non-alcoholic drinks. It is necessary to ensure that the grade of crown is suitable for the product being packed. Producers must ensure that the correct caps are specified for the particular product and purpose for which they will be used, e.g. drinks which are hot filled will produce a vacuum in the bottle and suitable caps must be specified. Bottle and cap manufacturers will advise but a range of tests must be undertaken to ensure that caps perform to the desired standard. They must not leak when subjected to likely levels of physical abuse and high and low temperatures over the shelf-life of the product, and adequate testing must be undertaken. Typical tests recommended by BSDA for the evaluation of closures are listed below.
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Note that production trials should be carried out if any change is made to the closure system in order to verify actual performance under production conditions. The following tests apply for plastic closures on plastic bottles (28 mm and 38 mm). Closures must perform over a range of temperatures and therefore tests are conducted at ambient (22 ëC), high (38 ëC) and low (4 ëC) temperatures. All tests are conducted with a carbonation level of 4:0 0:2 volumes of CO2 (8 g/L) where appropriate. Types of test include: · Pressure test Closures should not leak at pressures up to 175 psi (1207 kPa). · Top load vent test Closures should not vent when subjected to a top load of 100 lb (45.5 kg). · Removal torque test Closures up to 28 mm should release at <17 lb/in torque. Closures 28±38 mm should release at <25 lb/in torque. Bottles are tested dry 72 hours after filling. · Carbonation retention Bottles filled at 4.0 volumes CO2 are stored at 38 ëC, with and without 100 lb (45.5 kg) top load, and carbonation is measured at intervals for 12 weeks (at 1, 3, 6, 9 and 12 weeks). · Impact test A steel ball approximately 40 mm in diameter and 10 oz (286 g) in weight is dropped on to the closure from a height of 48 inches (1.2 m). The closure is on a bottle at 2 ëC and 22 ëC. Closures should not be damaged. · Drop test Bottles filled with product at 4.0 volumes CO2 are dropped vertically bottom first, on to a hard surface from a height of 5 feet (1.5 m). The test is repeated with the bottles dropped in a horizontal position. Tests are carried out at 2 ëC and 22 ëC. · Excess wax/oil test This is to test for absence of excess residual lubricants. Closures are stored at 38 ëC for 24 hours, placed on the full bottles and shaken. This is repeated using a total of eight closures. The surface of the liquid is examined using a magnifying glass for any traces of oily film or waxy deposits. · Tamper evidence Correct operation of the tamper evidence band is checked. 6.1.4 Where can I go for more help with packaging problems? The packaging supplier should be the first point of contact when a manufacturer is experiencing difficulties. For further advice and for an independent opinion there are commercial laboratories that specialise in solving manufacturers' problems, including packaging. In the UK these include companies such as RSSL and research establishments such as CCFRA. The Packaging Industry Research Association (PIRA) specialises in resolving packaging problems. Further information and guidance on packaging issues can be obtained from the Institute of Packaging (IOP) and the Metal Packaging Manufacturers' Association (MPMA).
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6.1.5 Do cans pose a risk of metal pick-up to soft drinks? Drinks cans are made from either steel or aluminium coated with an internal epoxy lacquer. The drink does not come into contact with the base metal surface. It is vital that the lacquer coating is free from any flaws (tiny cracks or holes), as contact with acidic drinks will cause corrosion of the metal. This will cause contamination of the product and eventually leakage from the can. On 22 May 2008 the European Food Standards Agency (EFSA) published its scientific opinion on the safety of aluminium from dietary intake. Major sources of aluminium in the diet arise from cooking acidic foods in aluminium vessels or foil and from certain food products, e.g. tea, which naturally contain aluminium derived from the soil. Aluminium cans do not contribute to dietary intake. Typical aluminium levels in soft drinks in aluminium cans are <1 mg/L. Contamination by iron from lacquer faults or damage in steel cans is not a health issue, but damage to the lacquer and consequent corrosion of the can will cause spoilage of the drink. Taste and spoilage issues would become apparent well before any harmful levels of dissolved iron could be reached. 6.1.6 What special problems are likely to be associated with the use of returnable glass bottles? The major operational problems encountered that are associated with returnable glass bottles are contamination and damaged bottles. The use of returnable glass bottles in the UK has steadily diminished to the point where only a few companies now operate such systems. Bottles are frequently returned in a very dirty condition, particularly when they have contained juice products which result in the presence of insects and mould growth. Additionally consumers may push drinking straws or sweet papers inside. Worse, they occasionally use bottles for storage of oil, paraffin, etc. Very effective cleaning and label removal by means of hot caustic detergent must be employed, followed by effective rinsing and electronic and/or human `sighting' to ensure that no contaminated bottles enter the filling system. Regular chemical checks must be carried out to prevent carry-over of caustic/ detergent on the washed bottles. Electronic sniffing equipment can be employed to detect volatile aromas present in the bottles from paraffin, solvents, etc. During their use by consumers and their return to the manufacturers glass bottles are subject to wear and tear and accidental damage. Chips in the rim are a common problem, preventing a seal being formed by the closure. Cracks and chips in the body of the bottles cause weakness which can cause a bottle to fail when pressurised for carbonation. Bottles must be checked prior to filling. In addition to accidental damage the bottles also suffer surface `wear and tear', termed `scuffing', from rubbing against each other. This scuffing gradually weakens the bottles and guidelines exist for bottles to be rejected once a predetermined degree of scuffing is reached. Bottles may have been weakened without visible damage and bottles are prone to burst in the filler. If this happens the filling head must be thoroughly
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cleaned and bottles around the broken one discarded to ensure that no small fragments of glass enter the bottles. Modern fillers do this automatically. Despite all the precautions taken during manufacturing, the consumer complaint rate for returnable glass bottles is generally at least an order of magnitude higher than for single-trip PET bottles. In addition to operational problems the use of returnable glass bottles presents logistical issues: · A stock of bottles and cases must be maintained to meet peak annual demand. This requires considerable capital investment which is unused for a significant part of the year. · The large stock of bottles means that any change of design is difficult and limited as the existing and new bottles must be compatible for production. · Even with a sizable deposit the return rate of bottles through the grocery system in the UK was only about 65%. 6.1.7 How does packaging relate to consumer expectations? Packaging is critical to the consumer expectations of a product. They would not expect a premium quality expensive product to be packed in a two-litre PET bottle. There are exceptions to this general rule. For example, fruit juices and smoothies in the retailers are packed almost exclusively in cartons and small PET bottles regardless of quality and price. However, even here there are distinctions, for example ambient stable fruit juices in tetrapak, chilled premium juices in gable-top cartons and freshly squeezed juices in bottles. The best example of consumer expectation can be taken from the bottled waters market where low-cost supermarket waters are packaged in generic two-litre PET bottles but waters intended for the premium hotels and restaurant trade (HORECA) are packaged in expensive designer glass bottles which will look attractive on a dining table. 6.1.8 What problems can I expect from the use of cartons? In tetrapak cartons the pack is produced in situ from rolls of printed laminate (cardboard, aluminium and polyethylene). The seams are formed in situ and the carton ends are sealed through the product. The major problems encountered are with poor seal formation causing leakage. The presence of fibres in juices can be particularly problematic as these can interfere with seal formation. The lengthways seam must also be checked regularly to ensure that the seal is forming correctly. As long-life ambient products are aseptically packed, maintaining sterility is an important concern. The filling plant must be maintained in a sterile condition and if stopped and opened because of a problem time is lost in re-establishing sterility. Loss of sterility will cause spoilage problems. It is important to cool the product sufficiently after pasteurisation prior to filling. Filling product at too high a temperature (>30 ëC) can cause flavour problems. The heat loss from the centre of a pallet full of cartons is extremely
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slow and packs in the centre of the pallet can stay at too high a temperature for days. This can cause flavour problems for fruit juices and also encourage the growth of any thermophilic organisms that may be present, e.g. Alicyclobacillus acidoterrestris. The use of sulphited juices in drinks packed into laminated board should be avoided. Any contact between the sulphite and aluminium in the laminate will cause the formation of hydrogen sulphide, evident by its offensive odour of rotten eggs. The sale of fruit juices in gable-top cartons such as Elopak and Combibloc has increased rapidly in the UK. These are distributed via the cold chain and hence care must be taken to maintain low temperatures at all times during distribution. Loss of control in the supply chain resulting in product reaching ambient temperature will cause spoilage. When laminate is stored in the form of a roll the interior of the pack is in direct contact with the exterior printed surface. Transfer of printing chemicals from the exterior to interior surfaces has been an issue and resulted in some product withdrawal in 2007. This problem has now been eliminated. 6.1.9 Are there any guidelines for sports closures? Some early designs of sports closures allowed children to bite or pull the end nipple off into their mouth, causing a potential choking hazard. Also some closures have tamper-evident dust caps on the top. These are frequently removed by consumers using their teeth, again causing a potential choking hazard. BSDA members, in conjunction with PIRA, produced a guide for sports closures which lays down specifications/standards to minimise the choking hazards. A guideline has also been produced for `flip lid' closures. These two guidelines are available from the BSDA.
6.2
Packaging defects
6.2.1 What are the most likely defects associated with glass bottles? Defects found in glass bottles can be classified as aesthetic, physical or critical failures: · Aesthetic This affects appearance of the bottle only and does not affect the integrity of the bottle. · Physical failure This is a fault which weakens the integrity of the bottle or would result in failure of the bottle during the filling process. · Critical defect This is a fault which would cause risk of injury to consumers, e.g. pieces of glass in the bottle. The most critical faults are the presence of threads or spikes of glass inside the bottle. These can be broken by the filling tube, leaving broken glass fragments inside the full bottle and posing a serious risk to a consumer drinking the product.
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Many flaws can potentially weaken the structure of the bottle, for example the distribution of glass throughout the bottle may be uneven, forming a weak thin area. Bottles may also be misshapen or have bubbles or other flaws. The BSDA publishes two booklets on glass bottle quality, Handling & Use and Sampling & Evaluation, which list 18 critical, 12 major and six minor types of defect. All deliveries of bottles should be statistically sampled and inspected for weight, height, volume, shape and any visible defects. A minimum of 125 bottles should be inspected. If any critical defect is found, the whole delivery should be rejected or quarantined until a full inspection can be carried out. 6.2.2 Are cans likely to show particular defects? The most common defects affecting cans are faults in the epoxy lacquer coating. Uneven application and `pin holing' will allow drink to contact the metal surface of the can and result in leakage. Leakage of a can will cause secondary corrosion of other cans and a whole pallet can rapidly be ruined. If cans are shrink-wrapped with excess moisture present, secondary corrosion, particularly of the scoring on the lid, will lead to leakage. The water used to rinse cans must not be aggressive or stress corrosion may occur where the lids have been scored to permit the tabs to open. Advice should be taken from the can manufacturers on the required water quality. The BSDA provides a guide on Environmental Stress Cracking of Aluminium Alloy Beverage End Scores. Cans must be as dry as possible when shrink-wrapped. The major fault during the filling process is faulty seaming of the lid on to the body of the can. If an imperfection is present in the seam, leakage will result. Regular routine seam checks are essential during production. Empty cans are extremely delicate and great care must be taken when moving pallets of them about. Any damage to the rim of the can will prevent adequate seaming and subsequent leakage. 6.2.3 What inspection regime do I need to put in place to minimise the risk of any defective container reaching the consumer? The monitoring of packs takes place both before and after filling. Electronic sighting devices can eliminate faulty glass bottles prior to the filler. Cans and bottles should be inverted and rinsed or air blown to ensure no solid particles are present. A range of continuous monitoring devices are also commercially available for placing on production lines after the filler to reject faulty bottles, e.g. · Electronic sighting can detect low fills or presence of foreign objects. X-ray detectors can spot low fills in cans. · Sighters can also detect faults such as closures that have not been applied correctly. · Sonic detectors can monitor the internal pressure and reject any `leakers'.
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Continuous monitoring of the performance of the line by the operators should detect any drift away from optimum operation before serious faults occur. Samples should be removed from the production line and inspected to evaluate the standard of seaming, capping, etc. The frequency of these checks will be ascertained by experience. The standard of application of secondary packaging should also be continuously monitored by the line operators. Where appropriate, microbiological testing should be implemented and samples from each production batch should be monitored. It is good practice to take three samples of each production batch and place them in storage until after the end of the shelf-life. These can be used as reference samples in the event of queries or complaints. They can also be inspected to evaluate whether the shelflife of the products is as expected. 6.2.4 Are there any types of defects that pose a special risk to the consumer? Most soft drinks and fruit juices are high acid (pH < 4) and defects result in spoilage of the product but not risk to the health of the consumer. Soft drinks do not support growth of pathogens. There are, however, some physical risks: · Glass bottles containing carbonated drinks are a potential hazard. Damage or weakness in the bottle could cause it to burst, resulting in pieces of glass causing physical injury. · Defects causing loose pieces of glass to be inside the bottle are a serious hazard. This could be caused by an internal defect in the bottle or by a filling tube striking the inside edge of the bottle rim and causing a small glass chip to fall inside the bottle. · If a cap is applied at too high a torque the consumer may use an unsuitable implement to try to remove it. This can result in injury due to the cap flying off. Many manufacturers put a warning `remove by hand' on caps to prevent this. 6.2.5 What is the best way to print `best before' or `best before end' (BBE) dates on containers? BBE dates can be printed on cans, bottles, cartons, etc., by means of a highspeed jet printer. The ink is sprayed onto the pack from a close distance at very high speed. The printer does not contact the pack. This has become the standard printing method and a variety of types are available commercially. This type of printer can be used on bottles, cans and cartons. It is important to ensure that packs are dry prior to printing and to choose a relatively flat place on which to print in order that the print is legible. One disadvantage of this type of printing is that the ink may be easily removed by wiping it with a solvent-soaked cloth. This enables unscrupulous traders to obtain out-of-date stock, remove the BBE date and reprint a new date. They then
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sell the stock as new, making a good profit. PET bottles may be etched by means of a laser. This etching is indelible but has the disadvantage that it is less easily visible than print. It is primarily applied to plastic, but its use on glass is becoming more common. 6.2.6 Are there any guidelines relating to clear labelling? The FSA has published an extensive guide to clear labelling on its website. The guidelines give advice regarding print size (minimum 8-point) and on use of suitable fonts and contrasting colours. Print layout is also covered. It is acknowledged that print size is not the only factor in legibility. The type of font and the contrast between print and background are also very important. The EU Commission is currently drafting its `Food Information Regulations'. These will lay down requirements for print size and clarity. The initial draft regulation proposed a minimum 3 mm font size for all mandatory information but this will probably be dropped following objections from the food industry and acknowledgement that for many small packs it is physically impossible.
6.3
Problems during filling and packaging operations
6.3.1 What are the most likely problems that can arise during packaging with any of the packaging types in regular use? Bottles Glass bottles, if new, must be inspected for any defects in production that might leave excess glass in the bottle or have any defect with the closure area. It is normal to subject all bottles to a clean water or sterile air rinse before filling. Glass bottles that have been previously used and rewashed must be inspected for debris, but because of the risk of contamination from other substances that may have been stored in the bottle, the use of an electronic `sniffer' device is also essential. Plastic bottles are almost always used as new bottles and should be subjected to an air or water rinse to remove plastic debris or dust particles. The most likely problem to arise when bottles of any type are used, apart from physical contamination, is a defect in the thread or closure resulting in a leaking container. Cans Cans are only used new and the most likely issue is that of the risk of physical contamination in the empty container, which can be covered by a pre-rinse. Most beverage cans are now two-piece (i.e. body and end) and the risk of leakage from side seams has been mostly eliminated. Other potential problems with the use of cans include the possibility of internal lacquering being of the wrong type or becoming detached from the metal surface. The possible interaction of product with any unlacquered metal surface must also be considered. Possibly the most likely packaging defect when cans are used is that of the seam of the
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applied end being distorted or ineffective, and regular monitoring of end seams is essential. Regular maintenance of the seamer is key to avoiding this problem. Form±fill±seal containers Many products are now packed in aseptic units using this technique. The main issues are those of forming packages with ineffective seams. Gross seam distortion is likely to produce leaking packs and less obvious distortion may lead to microbiological contamination. Close monitoring of pack seams is vital as is the appropriate maintenance of the filling plant. In aseptic filling machines the maintenance of sterility is also key to avoiding later problems with the end product. 6.3.2 Do such operational problems usually pose a threat to the integrity or safety of the product? Many defects in the packaging of beverages have the potential to pose a threat to the safety or integrity of the contents. The two main threat areas concern contamination of one form or another and product leakage. Glass bottles pose perhaps the most serious threat of physical contamination, as the presence of any residual pieces of glass in a container carries a risk of physical harm to the consumer and a consequent claim on the producer as well as possible loss of confidence. Any physical contamination is of course undesirable, but the presence of dust or other debris in a product is unlikely to have the same consequences as the presence of glass. Microbiological contamination also carries potentially serious consequences. Although most fruit juices and soft drinks are unlikely to harbour pathogens, the presence of any microbiological contaminant is unpleasant for the consumer. Yeast contamination also carries the risk of an exploding container which can cause injury and damage to property. The other area of risk, that of leakage of one or more containers, can cause damage to other stock or property and harm the reputation of the producer. 6.3.3 What process quality checks should be in place to minimise the consequential problems of packaging defects? For preformed containers, such as bottles and cans, the single most important step is to include a rinse of the container with either clean process water or sterile air. For transparent bottles a bottle inspection station is also very important. Traditionally this step was carried out by operators but it is now possible to include automated inspection equipment that rejects doubtful containers or diverts them for further inspection. Correct operation of capping equipment is also essential to ensure that cap threads are aligned with those of the body of the container and that no leaks are occurring. Can end application is key to maintaining the integrity of the product and appropriate checks of the quality of the seams are an essential part of the filling
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operation. Correct adjustment of the can end applicator determines the quality of the seam and close liaison between engineering and quality control departments is needed. Guidance and training on can end checks are usually offered by can or canning machinery suppliers. Important quality checks in the production of form±fill±seal containers are to some extent related to the nature of the container being produced, but all packs will require at least one seal that is essential to product quality. Equipment manufacturers usually provide guidance and training on the exact checks to be maintained. For aseptic plant, checks on the equipment to ensure sterility are important, and for reel-fed filling plant this may involve regular testing of the strength of hydrogen peroxide in the sterilising bath. Temperature checks, where necessary, can be monitored and recorded automatically and if required linked to alarms or divert/shutdown systems. 6.3.4 Do small changes in packaging need extensive trials? All changes in the design or specification of packaging should be assessed by technical, quality and production staff no matter how small or inconsequential they seem. Changes in material or wall thickness, for example, can alter the oxygen transfer rate of a plastic container and thus affect the stability of the product or the physical strength of the bottle. Changes in the weight of a glass bottle may alter the ability of the bottle to withstand pasteurisation or a particular level of carbonation. Seemingly small changes in the specification of the liner of a bottle cap or the seam compound applied to can ends can, for example, affect the performance of the seal which may only be noticed when a particular temperature is reached. It is therefore important to ensure a close liaison between all the departments that may be involved. The pressure to change a design may come from a marketing department, or the apparent potential to make savings will be very attractive to a purchasing department. There are many examples where seemingly small packaging changes made for the best of reasons have had undesirable consequences on either product quality or company reputation. Many packaging changes can have beneficial effects and individual manufacturers will want to have procedures in place to ensure that proposed changes are fully assessed before being put in place. In some cases, it will be possible to assess the proposed change without extensive trialling, while in others a full product life storage trial may be needed. 6.3.5 At what temperature should containers be after filling? There is no blanket guidance that is appropriate to this question as it will depend on the product, the processing it has received, the type of packaging and the environment in which production is taking place. For carbonated products most manufacturers will probably wish to fill at temperatures of below 10 ëC to
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minimise the filling pressures. Filled product will therefore be at a low temperature and, depending on the dewpoint of air in the production environment, condensation may form on the outside of the containers. If cans are placed into secondary packaging in this state, corrosion is likely and will result in an unsightly appearance of product and, in time, leakage. Bottles may require labelling or other marking that cannot be applied to wet surfaces and so for this situation it may be necessary to subject filled product to can or bottle warmers before drying in an air blast. Another example is that of bottles or cans exiting from a tunnel pasteuriser where they have been subjected to water sprays. Containers then need to be at a temperature at which the surface water can be quickly dried off. If this is not carried out there is a significant risk of can corrosion occurring. Products that are at too high a temperature (over about 25±30 ëC) may need cooling. When a large number of packs are placed together in this condition in their secondary packaging on a pallet or other bulk aggregation, the phenomenon of `stack-burn' may occur. This results in the contents of packs at the centre of the stack becoming slowly cooked. The effect is likely to be product browning coupled with a noticeable processed taste. In general, end product should be free from condensation where this may affect subsequent quality, and should be at a temperature that is appropriate to their nature and likely to ensure the best quality is maintained. Once products are filled and labelled, storage at temperatures between about 5 and 20 ëC is usually satisfactory (unless the product is to be sold chilled). Products should not be exposed to sub-zero temperatures that may result in freezing, leading to possible rupture of containers. 6.3.6 What are appropriate carbonation levels for different products and container types? The desired level of carbonation varies markedly for different product types as shown in the table below: Product type
Lightly sparkling Fruit juice carbonate Lemonade Cola Mixer
Typical carbonation levels Volumes
g/litre
2.0 2.5 3.0±3.5 4.0 4.5±5.0
4 5 6±7 8 9±10
Selection of the container and closure and any fine tuning of carbonation level will need to reflect the level of carbonation desired and the likely usage
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pattern of the product. For example, a large (e.g. two-litre) bottle of cola may not be consumed at one time and the carbonation level and pack will need to be capable of retaining a reasonable level of gas during the period of ullage. Any processing (e.g. tunnel pasteurisation) of the product must also be taken into account when selecting the container and closure type, as internal pressure within the bottle is likely to increase markedly during the process. The selection of secondary packaging should also be a consideration as it will be likely to affect the protection given to the primary container during transit.
6.4
Post-filling defects
6.4.1 What are post-filling defects and how do they arise? Post-filling defects, i.e. those defects that arise after the container has been filled and closed, can occur at any stage during the life of a product, although they are most likely to be noticed either immediately after filling or some time into the life of the product. Defects occurring immediately after filling are most likely to be related to the taste or appearance of the product, assuming that the process control parameters are all within the allowed tolerances, and batch tasting is an important release criterion. Examples of appearance defects may be the presence of particulate material, lack of cloud in a cloudy product, incorrect colour level or the presence of a foreign body. Release criteria should specify, as precisely as possible, the acceptable range of appearance of fresh product including, if relevant, colour and cloud density specifications. Special considerations may need to be applied if product is to be in-pack pasteurised (see 6.4.2). Taste and appearance defects can then arise during the shelf-life of the product, and the behaviour of normally acceptable product during its shelf-life must be assessed and recorded to effect comparisons with defect samples. In addition to the more obvious issues, defects may arise during storage that are related to levels of active ingredients such as ascorbic acid. Specific problems can occur as a result of changes in water analytes (e.g. an increase in iron content is likely to affect colour) and also from naturally occurring phenomena such as summer algal blooms in a reservoir that can transfer flocculant polysaccharides to the product. Products containing fruit components are susceptible to the presence of excess pulp or the separation of fruit into clear and cloudy layers as a result of pectolytic activity in the fruit component. 6.4.2 What special problems are posed when filled and closed packs are subjected to tunnel pasteurisation? The process of tunnel pasteurisation involves pre-filling and closure of the product, subjecting it to heating to pasteurising conditions (typically 70 ëC for about 20 minutes) and then cooling for any label application or secondary packaging. The process subjects the container to considerable thermal stress and the immediate consideration is selection of the container/closure combination
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that will withstand the stresses, with appropriate preheating steps and cooling regime. Glass bottles and cans are usually the preferred packages for this process and both must be capable of withstanding the additional internal pressure if carbonated products are being manufactured. For non-carbonated products, cans are likely to require pressurising with nitrogen gas to avoid distortion during processing. Some breakage of glass bottles may occur during the process, reflecting defects in the packaging, but if their number becomes significant the container may be deemed unsuitable or some modification may be required to the process steps (e.g. temperature of the preheating stage). Products need to be scrutinised for any heat effects such as colour browning or the presence of a cooked taste. It is important to assess the shelf-life of products pasteurised in this way as the heating process may, in some products, reduce the acceptable shelf-life. On completion of the tunnel pasteurisation process, containers must be dry before any labels are applied or, in the case of cans, to minimise the risk of corrosion. Products should also be cooled to below 25 ëC before secondary packaging is applied to minimise any risk of further heat damage. 6.4.3 Are there any particular problems that can arise after secondary packaging is applied? Secondary packaging is defined as additional packaging that has no direct influence on the primary or original container that is ultimately bought by the consumer. It is used to ensure that the primary package will fulfil its containment purpose and marketing function. Traditional secondary packaging usually employed corrugated board cases, often with dividers, that provided both strength and cushioning, but since the advent of PET and other plastics the level of protection needed has changed and much wider use is now made of shrinkwrap and tray cases. The main risk that is likely to apply to the primary product is thus that of mechanical damage or the ingress of light through the secondary packaging. Packaged beverages are quite heavy, particularly when shipped on pallets or in cages, and however effective the primary packaging is, the product will not achieve its best sales potential if the issues of support and damage protection during transit are not appropriately addressed. Whether secondary packaging comprises trays, wraparounds, cases or even flat sheets, the rigidity of corrugated board continues to play a significant part in the safe handling and distribution of beverage containers. Computerised models now exist that give the packaging technologist insight into the stresses on pallet loads and the hazards arising from storage and transit conditions. Such models can assist in determining quantities and collating arrangements for packs of individual products or mixed loads with the objective of delivering primary product in the best possible condition.
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6.4.4 What causes TEBO and what is the function of vertical slots in the threads of bottles containing carbonated drinks? TEBO (tail end blow off) occurs when the closure is opened quickly and the gas cannot vent fast enough to allow the pressure in the bottle headspace to equate to atmospheric pressure before the closure is actually removed from the bottle neck finish. There have, in the past, been instances where caps of carbonated products being removed by consumers have become missiles caused by a sudden explosive release from the container body. Such a release has caused both personal injury and damage in a small number of instances. An industry response to this problem has been to redesign containers to allow a controlled release of carbon dioxide gas as soon as pressure has been released but before the cap has been released from its contact with the screw thread of the bottle. Modification of bottle thread design to incorporate the vertical slots that permit a controlled release of gas through the slots as soon as release of carbon dioxide top pressure takes place has now virtually eliminated the problem of caps becoming missiles without compromising the sealing qualities of the unopened combined package. An alternative approach that is achievable with plastic closures is to build the slots into the thread within the cap; this avoids the cost of new bottle moulds. 6.4.5 What is stress corrosion of cans and how may it be prevented? When beverages are packed into cans the product temperature is often below ambient, especially if the product is carbonated, and condensation will form on the outside of the can. This can be a particular problem in conditions of high humidity. Stress corrosion of cans occurs irregularly when containers are packed wet and may lead to a large number of cans leaking, with the resulting commercial loss. The risk of stress corrosion may be substantially eliminated by utilising a tunnel pasteuriser as a can warmer to increase the temperature of can and content above the dewpoint. However, in these instances it will be essential to ensure that any residual moisture on the outside of the can is removed before secondary packaging is applied. Removal of final traces of moisture is usually effected by a strong airflow over the containers. If the canned product is to be pasteurised anyway, the problem is unlikely to occur, but drying of containers is still essential before secondary packaging is applied. The potential problem can be further reduced by using perforated shrink film as the secondary packaging and by monitoring the amount of moisture remaining on individual cans. Ideally this should be at or below 10 milligrams per can. The mechanism of stress corrosion is still relatively unknown but the problem arises from the need for manufacturers to form the score for the can opening. This requires the score to be made through the lacquered metal of the can end and this appears to be the site at which corrosion occurs.
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6.5
Storage conditions
6.5.1 How can I monitor the range of conditions likely to be experienced by my products between manufacture and consumption? Products can be subjected to a wide range of conditions during storage and distribution, including extremes of heat, cold and physical stress. It is important to minimise these extremes in order to maintain products in optimum condition and to prevent physical damage. Wherever possible the distribution chain should be audited to ensure that the handling conditions are suitable and that stock control is satisfactory. Generally, the distribution chain has improved significantly in the past decade for several reasons, e.g.: · Reduction of stock handling and shorter delivery times for commercial reasons · Increased management focus on distribution logistics as a critical function · EU legislative requirements for traceability and use of computerisation and bar coding for product tracking and handling. Electronic equipment designed to record temperature/time and physical impact during distribution are available and consultancies can be hired to investigate and monitor the distribution chain. Recording devices can be placed inside pallets of product and the conditions encountered can be evaluated by interrogation afterwards, similar to a `black box' recorder in an aeroplane. Control of the distribution chain has become increasingly important as both primary and secondary packaging have been both light-weighted and reduced in quantity and as the volume of drinks, especially juices and smoothies, distributed via the cold chain has increased. Monitoring of temperature during distribution is critical for short shelf-life products in the cold chain. If the product is allowed to reach ambient temperature its condition and shelf-life will be seriously compromised. 6.5.2 What level of handling abuse do I need to consider when specifying secondary packaging? For environmental and cost reasons the quantity and weight of packaging has been significantly reduced over the past two decades. The weight of glass and PET bottles and cans has been reduced by up to 25% since 1990. However, improvements in manufacturing technology and pack design have enabled this to be achieved with only minimal, if any, reduction in overall pack strength. Modern automated pallet handling systems generally subject products to less physical abuse than the older manual handling systems but a certain degree of physical abuse is inevitable during transportation. If long journeys, particularly overseas, are anticipated it is strongly advised to substantially improve the degree of secondary packaging. If product in colourless bottles is light sensitive then use of UV-absorbent secondary packaging is recommended. Some older warehousing may subject stored product to excessive light, humidity and temperature fluctuation.
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Modern warehouses are usually racked but smaller and older storage facilities may stack pallets of product directly on top of each other. This practice can result in considerable pack damage if not conducted correctly. In the case of bottles, placing excessive weight on top of a pallet or placing one pallet on top of another without adequate care can result in serious damage to closures. In the case of cans and cartons such crushing will result in damaged packs, split seams and leakage. Whilst stronger (more expensive) secondary packaging will reduce pack damage, the only solution is to improve pallet handling along the distribution chain. 6.5.3 How quickly, in the event of a product recall, can I trace and withdraw a particular batch of product from storage and distribution? The ability to trace and withdraw a given batch of product depends upon the type and length of the distribution chain. When product is delivered directly from factory warehouse to retailer depot, withdrawal can be achieved rapidly and relatively simply. However, distribution chains in the licensed trade and through cash and carry operations may be considerably longer. It is a legislative requirement within the EU (Hygiene Regulations 2004) to maintain a traceability record in order to withdraw product. A record must be maintained of the supplier of all materials received and the recipient of all products dispatched (the so-called one-up-one-down principle). Longer, more complex supply chains will of course be slower to react. It is important to note the difference between `recall' and `withdraw' as used by the EU authorities and the FSA. `Recall' means that all product within the distribution system, up to and including the retailers' shelves, is removed from sale. `Withdrawal' means that product already in the hands of consumers is also retrieved. This may require considerable national advertising if the product has been distributed nationwide. In the event of a recall, major retailers aim to remove products from their shelves within 24±48 hours (usually 24). Recall of products distributed via cash and carry is more difficult. Full pallets can be tracked to cash and carry depots but once full pallets are opened and product is purchased by individual small retailers, cafeÂs, etc., traceability is lost. Labelling of batch codes is advised as this can assist withdrawal or recall by limiting it to specific batch codes. If production is date coded only then a batch will be one date code. The labelling of products to identify batches or production lots is required by the Food (Lot Marking) Regulations 1996 SI 1502. 6.5.4 Are there particular storage conditions for my products that need to be avoided? Products should be stored in cool, dark, dry, clean conditions for the following reasons (see also Section 4.6): · High temperatures accelerate product ageing and reduce shelf-life. An increase of 10 ëC in the storage temperature can almost halve the shelf-life of products, particularly juice products.
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· Freezing temperatures Water expands when it freezes and will cause pack damage. Partial freezing can cause product separation and sedimentation. · Fluctuating temperatures can destabilise emulsion systems, causing product separation and sedimentation. They can also result in condensation on the exterior of the packs, causing can corrosion and damage to labels and cardboard packaging. · High humidity and moisture cause corrosion of metal cans, pack damage and mould growth. · Sunlight causes flavours/colour deterioration in susceptible products in clear bottles. In bottled waters sunlight can result in algal growth, causing a green discoloration. Intense sunlight over a prolonged period will cause fading/ discoloration of packaging. · Cleanliness Products should always be stored in clean conditions to prevent pack spoilage and to discourage pests which will also cause pack damage. 6.5.5 What effect are strong aromas likely to have on stored products? Unlike glass and metal, plastic is slightly permeable. This is why carbonated drinks in PET bottles slowly lose carbonation as the CO2 permeates outwards. However, this permeation can occur in both directions. Atmospheric oxygen can permeate into the bottle, causing oxidation and staling of products. Likewise, aroma molecules in the atmosphere can penetrate into the product. Bottled water is much more susceptible to such taint because it is relatively tasteless and the presence of any contamination can be detected organoleptically at very much lower concentrations than in a strongly flavoured soft drink. The effect occurs only slowly but storing water in plastic bottles for many weeks in the presence of a strong aroma, such as detergents, disinfectants, etc., can lead to significant tainting of the water. This effect can happen to any food or drink products packed in plastic, e.g. pouches, though the use of aluminium layers will significantly reduce permeation rates. Waters in plastic bottles usually advise `store away from strong aromas' on the label.
6.6
Distribution problems
6.6.1 How much do I know about the distribution network that handles my products? It is beneficial to ascertain as much information as possible about the distribution chain to help minimise damage in transit. Traditionally, distribution of drinks from factory to customer was undertaken either by the manufacturer's own fleet of transport or by hired transport. The increasing involvement of specialist logistics companies and the major retailers has simplified and improved distribution. Many manufacturers have outsourced the distribution of their products to specialist logistics companies, who deal with the day-to-day
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issues and ensure optimum efficiency. In the UK major retailers are moving towards `factory gate pricing' systems where they are responsible for the transportation of products from manufacturing sites to their distribution centres. Whilst such outsourcing of transport activity removes responsibility from the manufacturer, it has resulted in a loss of control. Distribution of whole pallet loads through highly automated modern warehouses is likely to be less hazardous than distribution of part pallet loads through small regional operations for local small retailer and cash and carry outlets. The breaking down of pallets into smaller loads for final distribution is where the majority of minor damage will occur because of the repeated manual handling. Manufacturers should be aware of the distribution system through which their products are passing, the transport companies and systems involved. 6.6.2 How much control do I have over the distribution network? Obviously, whilst product is in your own part of the network, i.e. your own lorries and warehouse facilities, it is still under your control, but once handed over to distributors, wholesalers, cash and carry operators, etc., any control becomes much more difficult. This is even more true for very small manufacturers who have little influence over distributors. It is important to keep detailed records of any problems encountered during distribution in order to be able to hold those responsible to account. Statistical analysis of complaints or problems encountered over a period of time may demonstrate that a significantly higher percentage arise from one particular depot or transporter. This evidence can then be used to seek remedy from the perpetrator. Having confidence in your distributor is important, particularly for cold chain products where temperature control and regular deliveries are essential. Where possible ensure that any essential conditions are stipulated in the distribution contract with appropriate penalties for breach of contract. 6.6.3 Are there places where products are likely to be distributed out of order? In modern automated warehouses a bar code system for logging pallets in and out will be in operation. Every pallet has an individual barcode attached; this is read and the location of the pallet in the racking is recorded in the computer. When product is requested for onward distribution the system will automatically seek the oldest pallet in its record. This system is known as FIFO (first in, first out). Smaller and older manual (paper) systems tend to be less reliable. The system is only as good as the operator. Many small and old storage depots do not have racking for pallets, especially for glass bottles in plastic cases which may be stacked three or four pallets high. It is easy for pallets to be misplaced in such a system and consequently left behind, out of sequence. Operating FIFO in such depots requires good manual discipline and paper operating systems. The use of pallet racking with a roller system helps to keep distribution in the correct
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sequence. Such racking systems have the racks on a slight slope and rollers to enable pallets to roll forward under gravity. New pallets are loaded into the racks from the higher end and pallets for onward distribution are taken from the lower end. The row of pallets then moves forward one space. The problem of out-of-sequence usage can apply to cash and carry depots and to retailers when stock is both removed and replenished from the front of a stock of packs. Operatives must be trained to locate older stock to the front and place the newer stock at the rear when replenishing products. 6.6.4 How can damage during distribution be minimised? Several options are available to minimise damage during distribution. However, all of them will add significant on-cost and the best solution is to improve the handling during distribution. Options for increasing the strength of the pallet are as follows: · Redesign the pack Bottles can be designed to be stronger and more resistant to crushing by inclusion of ribs and/or panels, though this may add additional weight. · Heavier bottles Increasing the thickness of PET and glass bottles will generally make them stronger. · Secondary packaging Using heavier and higher grade cardboard. · Pallet protection Heavy-duty layer pads, corner and side protection, and secure stretch wrapping. · Pack stacking Optimised interlocking of packs on a pallet for increased stability, and no overhang of packs outside the area of the pallet. · Additional protection if being transported in a container on a ship.
7 Handling consumer complaints about soft drinks and fruit juices Abstract: This chapter lists and answers key questions relating to handling consumer complaints about soft drinks and fruit juices. It covers recording and handling consumer complaints, traceability systems and crisis management. Key words: soft drinks, fruit juices, consumer complaints, traceability systems, crisis management.
7.1
Recording and handling consumer complaints
7.1.1 What system should be in place for handling complaints? Complaints always arise despite the best efforts of manufacturers and one issue to be addressed at the outset of setting up a handling system is to decide what constitutes a complaint and which department within a company is best placed to handle them. It is recommended that any adverse remark about a product be treated as a complaint as it is not always possible to know whether such comments may be the first hints of a more serious problem. Smaller producers may wish to deal with complaints handling within another department and it can sometimes be comfortably accommodated within a marketing operation. Complaints handling by a sales department may lead to a conflict of interest. Larger manufacturers will usually have a separate department. Efficient handling of complaints can be a positive marketing tool as consumers usually react well to a complaint handled swiftly and effectively. It is thus essential that any complaint be handled quickly. This is particularly important if the complaint arises from an enforcement body or a major trade customer or in any situation where a recall of product becomes a possibility. In
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the past, manufacturers sometimes responded to complaints from individual consumers by sending the complainant replacement product(s) or cash in the form of a postal order or even a cheque. The cost of sending replacement product to individuals is now prohibitively expensive and most manufacturers now respond by sending vouchers for replacement product to encourage the consumer to remain loyal to the brand. Complaints from trade customers will usually demand replacement product and may also incur financial penalties. To cover the extreme eventuality, manufacturers will need to have in place procedures for both a trade and a general consumer recall. Complaints must be reviewed regularly within the company quality system and it is recommended that reports of serious complaints and their consequences should be reviewed at board level. 7.1.2 How should complaints be classified? It is the responsibility of manufacturers to set up a system that suits their particular need, but the following areas are likely to be important in classifying complaints: 1.
2.
3.
The complaints should be classified in terms of the complainant, e.g.: · Individual consumer · Solicitor on behalf of individual consumer · Trade customer · Enforcement authority · Other. Complaints should then be divided into those relating to: · Product · Packaging · Labelling · Price · Distribution. Individual companies may then wish to subdivide complaints further to take account of matters such as different manufacturing locations, distribution chains, retailers, sales areas and so on.
Records should be kept detailing all complaints in such a way as to enable year-to-year comparisons and trends to be monitored. Complaints and the way they are handled are an important indicator of a company's consumer relations and many company boards insist on regular reports. Whether or not reports are seen by board members, they should be regularly reviewed by the quality management team within a company and records kept of corrective action that is considered necessary as a result of complaints arising. Any complaint recording system must have in place the ability to identify rapidly any event(s) that are so serious as to trigger a partial or full product recall.
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7.1.3 Do customer complaints need to be justified? The justification of complaints may not appear as an important issue in developing consumer relations, as many companies will wish to take the view that any concern expressed by a consumer must be addressed so as to give full satisfaction. However, the justification of complaints is essential in determining any real problems within the formulation, packaging, manufacture, distribution or sale of the products of a company. For this reason it is strongly recommended that significant effort is put into the justification of all complaints. To achieve this, an organisation will need to have in place a system of handling complaints speedily which will both acknowledge receipt to the complainant and pass on the details to the appropriate department for investigation. To enable justification to be undertaken, it may be important to recover the complaint sample wherever possible, although with beverages this will often present difficulties. Where no product recovery is possible, the complaint will be unlikely to be fully justified unless it is one of a series of similar events. Sample examination will usually be offered when the complaint has arisen from an enforcement authority. Serious complaints such as the presence of a piece of glass or metal in a container of product must involve laboratory examination of the offending contaminant, as there are many examples of consumers attempting to take advantage of manufacturers by presenting false claims. In such instances it is essential that the complaint is justified in order to determine the validity of any claim against the manufacturer. 7.1.4 What procedures should a manufacturer have in place to identify the likely cause of complaints and any corrective action necessary to prevent their recurrence? As a minimum, manufacturers should have in place a complaint classification system similar to that set out in 7.1.2 to identify the type of issue. Although all complaints should be scrutinised, it is likely that only justified complaints are likely to be investigated in detail and possible corrective action identified. Upon receiving a complaint, an appropriate classification is allocated to the issue and it is normally passed to the appropriate department for further consideration. The quality assurance team will, in many companies, be the coordinating department. Complaints about the nature of a product should prompt examination of the manufacturing records to establish that there were no errors in either the product make-up or its processing. If other similar complaints are received it may be necessary for the company research team to re-examine the product formulation to ensure its fitness for purpose. Similarly, any packaging complaint is normally referred to the manufacturing team to establish that materials were within specification and that no machine faults were to blame. Issues relating to labelling, distribution or price are more likely to be referred to the marketing department.
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It is justified product or process complaints that are most likely to lead to corrective action within a manufacturing operation. Justified complaints relating to labelling or distribution may require a label change or some action by the logistics coordinator relating to the method of distribution. 7.1.5 How quickly should a manufacturer respond to complaints? All complaints, from whatever origin, should receive a reasonable response from the manufacturer or distributor but there will usually be a system of priorities. Any complaint from an enforcement authority should receive as rapid a response as possible and certainly within one working day. The response time and attitude of a manufacturer or distributor may be a factor in the subsequent decision by the authority as to whether or not to prosecute, assuming an offence has been alleged. Whilst there is an important issue about the reputation of a company at stake if it is prosecuted, the fines likely to be levied are in most cases modest, although in recent prosecutions of a multinational company substantial amounts have been imposed. From a commercial standpoint a complaint from a major customer, particularly if the customer is a national supermarket chain, has the potential to cause much more economic damage to a manufacturer than is likely to be inflicted by the fines and costs from a successful prosecution. In practice, therefore, most manufacturers will treat any complaint from either an enforcement authority or a trade customer with equal priority and seek to respond within a matter of hours. Complaints from individual customers must not be neglected and in many organisations will be handled by a separate department to that dealing with issues arising from an enforcement body or a trade customer. Complaints from individual customers should be acknowledged in writing by return and any subsequent investigation advised as soon as it is completed. The key to rapid responses to complaints is to have effective traceability of ingredients, batch manufacture and distribution records. Thus, if a complaint arises, suspect batches can be identified, traced and if necessary quarantined pending further investigation. 7.1.6 How can situations likely to result in a product recall be identified? Product recall is a serious step for any organisation as it is effectively a public announcement of some failure within the company operation. Recall may be effected either at trade level or, in the most serious situations, by means of a full public recall triggered by announcements in the national press. The decision to carry out any recall is usually taken at a very senior level within a company on the advice of technical and marketing departments. Product recalls usually arise either from a series of related complaints that indicate a widespread problem with product that has already been distributed (e.g. a microbiological contamination that has affected a large amount of
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product) or because the company has become aware of a problem internally (e.g. excess level of a preservative) that renders a product unsafe for consumption or unfit for sale. The receipt of complaints of a similar nature from individual customers is often the first hint of a major problem and any rapid increase in complaints from one day to the next can indicate a major problem. There is anecdotal evidence that for every customer who takes the trouble to contact a manufacturer there are at least 10 more who have not responded. Staff handling routine customer complaints should be advised to alert senior staff in such an event so that the consideration of a recall can be made. Other issues can arise from review of process control checks or possibly a notification from a supplier of a problem. With the trend to just-in-time supply, many manufacturers do not hold stock for sufficient time to finalise all possible checks before stock is distributed. In such situations, the discovery of a problem can create the need for a recall, although depending on the length of the supply chain it may be possible to limit this to trade distributors. In the United Kingdom, the FSA seeks voluntary cooperation from manufacturers and distributors to register `quality incidents' on its website www.foodstandards.gov.uk.
7.2
Traceability systems and crisis management
7.2.1 How effective should a traceability system be? Within the EU it is a legal requirement for food manufacturers to have a traceability system in place (Regulation 852/2004). At a minimum, it must always be possible for a manufacturer to have in place `one up, one down' traceability. This means that it must be possible to track the use of every individual batch of each ingredient, including packaging components, through to manufacture of each and every product and then to be able to follow the distribution of every manufactured product to its next destination. Other manufacturers will want or need to have in place more elaborate traceability. This is particularly likely to apply if, for example, products designated as organic are being produced when it will be necessary for full traceability of the organic constituents to be available. Because of past problems of adulteration, many juice packers will also wish to have full traceability of the origin of their bulk juices as part of their due diligence process. Traceability systems can be either electronic or paper-based but the essential feature must be that of rapid and complete access to the information. Increasingly, manufacturers are using electronic systems because they allow access from multiple terminals in different departments and are increasingly more reliable than paper-based records.
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7.2.2 Who needs to be in a crisis management team to deal with any major incidents? Major incidents within a company will be likely to include product recall but will also include events such as a major fire, serious machinery breakdown, and similar events that could have a major impact on the company's operations or finances. The make-up of a crisis team to deal with any major incident will vary from company to company but is probably likely to include the following or their nominated representatives: · · · · · ·
Managing Director/Chief Executive Marketing Director Operations/Production Director Distribution Manager Engineering Manager Quality Assurance Manager.
Additionally, many companies will wish to include their in-house or external legal advisers, insurance brokers and public relations executives and other nominated individuals or departments. Some organisations will also wish to nominate external specialist companies to assist in certain circumstances. The management of major incidents may be critical in ensuring the ability of a company to continue manufacturing or, in extreme circumstances, in securing its very survival, and it is essential that callout lists are circulated so that in the event of a crisis occurring, it is possible to contact key individuals on a 24-hour basis. Depending on the nature of the incident, a cascade system to call out other key personnel as necessary should also be in place. Companies may also wish to draw up major incident plans which can be referred to if and when a crisis occurs so that there are predetermined activities and roles to ensure the smooth running of a crisis organisation. 7.2.3 When is it necessary to obtain expert assistance in the event of a contamination incident? Most companies have laboratories that are designed to support their day-to-day activities and as such are unlikely to be able to offer much support to identify a contamination incident. The majority of untoward contamination incidents for most companies are likely to be of microbiological origin and there may often be a straightforward explanation such as failure of packaging or process. However, when it becomes necessary to carry out the identification of a contaminating micro-organism, it will almost always be necessary to involve an external specialist laboratory. Suspected chemical contamination in a product, unless an excess of one normal ingredient is the likely cause of the problem, will almost always require the input of a specialist laboratory. If the incident arises from suspected deliberate interference with product, it will also be important to require the
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laboratory to have validated procedures and to be able to present expert evidence if required. Problems of taints are often very difficult to determine and may also require the expertise of laboratories that specialise in identifying the chemical nature of the taint. Problems of physical contamination often relate to pieces of packaging materials, the most serious of which is glass. The use of glass as a container can sometimes lead to small pieces being present in the filled container, but the presence of any glass in any container of product should be subjected to external laboratory examination. Spectrographic examination of the glass can determine its likely origin and thus indicate whether its presence is likely to be accidental or deliberate. Metal contamination should normally involve the services of an external laboratory to identify the nature of the metal, which may give some clue to its origin. The use of an external laboratory to assist in identifying other physical contamination will probably be decided on an ad-hoc basis. 7.2.4 Where can further assistance be obtained to deal with complaints of a serious nature? Depending upon the nature of a complaint, assistance may be obtained from a number of different sources, including independent consultancy firms. If the complaint is of an issue that is potentially harmful to customers then the Food Standards Agency or the local authority's Environmental Health Department may be able to offer guidance on the issue of recall and customer advice. Very serious health issues (which are most unlikely to affect consumers of fruit juices or soft drinks because these low pH products do not generally support the growth of pathogenic micro-organisms) will often involve the Health Protection Agency, the Department of Health and the local Director of Public Health and be taken out of the hands of the company concerned. Technical issues that require more facilities than the company concerned is able to handle in-house can often be usefully referred to an outside laboratory such as one of the many Public Analysts laboratories, or to specialist laboratories such as RSSL, Leatherhead Food International or Campden BRI. If advice is required concerning the identification of taints then additional facilities such as those of Sensory Dimensions need to be consulted (see below). Issues that are likely to have a wider impact than simply those of the company concerned may often be usefully referred to a trade organisation such as the British Soft Drinks Association or the British Fruit Juice Association or the relevant organisation of the country concerned. Technical problems that relate potentially to ingredients of product or packaging should be referred to the suppliers, since many such organisations have detailed technical knowledge that can prove invaluable. Contact details for the above organisations are as follows:
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· Campden BRI, Chipping Campden, Gloucestershire GL55 6LD, UK Telephone +44 (0) 1386 842000 Email:
[email protected] · Leatherhead Food International, Randalls Road, Leatherhead, Surrey KT22 7RY, UK Telephone +44 (0) 1372 376761 Email:
[email protected] · Reading Scientific Services Ltd, Reading Science Centre, Pepper Lane, Whiteknights Campus, Reading RG6 2LA, UK Telephone +44 (0) 118 986 8541 Email:
[email protected] · Sensory Dimensions, Science and Technology Centre, Earley Gate, Whiteknights Road, Reading RG6 6BZ, UK Telephone: +44 (0) 118 935 7000 Email:
[email protected] 7.2.5 Is it advisable to have a public relations advisor to deal with serious complaints? Every company will always hope that it never has a complaint issue to handle that is of such severity as to need the advice of a public relations (PR) specialist. However, many companies, and particularly those with important brands to manage, will probably retain the services of a PR company to handle the positive side of their business in relation to new product launches, key appointments and other matters that are likely to be of interest to consumers, customers or the trade. It is then a relatively small step to extend the brief of the PR company to handle matters that relate to serious complaints, product recalls or other related issues. The PR consultant should, in the case of a potentially damaging complaint, be among the first people to be alerted on the company callout plan. Companies that do not use the services of a PR company on a more regular basis should consider having a retainer agreement with a suitable organisation so that in the event of a serious complaint they can become involved. The benefits of using PR specialists can ensure that however good the internal organisation of the company, the issues are presented in an appropriate and professional manner to the right media. 7.2.6 When do product problems require that enforcement authorities be informed and when should a product recall be instituted? Enforcement authorities may sometimes be informed if a complaint or series of complaints arise that indicate a problem which may possibly cause harm to consumers. In parallel with advising such authorities, a product recall will probably be initiated. This will usually depend on the circumstances so, for example, if a manufacturer becomes aware that a batch of product has a yeast infection and is likely to cause containers to explode, advising the enforcement authority will be likely to depend on how far the infected batch(es) have been distributed.
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If a limited amount of product has been distributed to identifiable wholesale depots, it may be possible to institute a trade recall, in which case it may not be thought necessary to involve the enforcement authority. If the product has been more widely distributed and is likely to have been purchased by the end consumer, a product recall and notification become more likely. Identifying the range of different circumstances that are likely to trigger recall and notification is difficult but, as a general guideline, if a batch of product can possibly cause harm to consumers, the recall and notification procedure should be started. The most likely causes are chemical, physical or microbiological contamination. It is sometimes very difficult to decide when an individual complaint from a consumer represents an isolated incident or is the first hint of a more widespread and possibly serious problem, and for this reason alone all complaints, no matter how seemingly trivial, should be carefully scrutinised and mapped. When complaints arise from the enforcement authority, the decision to recall may be taken away from the company and be initiated by the authority. As previously indicated, all companies should have a clear recall procedure which should be regularly tested in a desktop exercise. In some countries there is a move by enforcement bodies and liability insurers to be given evidence of `dry run' recalls as a requirement of continued operation. 7.2.7 What should be regarded as a complaint and what is a typical level of consumer complaints? There is sometimes a tension within a company as to just what constitutes a complaint and some departments within an organisation may take differing views. For example, sales and production departments may see complaints as a poor reflection of their efforts and may wish to eliminate what they consider as trivial matters. However, it is not always simple, on the basis of one or two complaints, to determine whether it is the start of a more widespread problem, and the normal recommendation would be for a company to log all consumer responses, no matter how seemingly trivial. Complaints are best handled by an independent department which in many organisations is linked to the quality assurance team who can take a dispassionate view and identify trends and serious issues. It is also recommended that complaint report summaries should be presented to the senior management team in the organisation. Different companies will be likely to set their own standards for complaints but experience shows that for soft drinks and fruit juices a low level (e.g. 1±5 complaints per million) is regarded as `normal' (on the basis that some consumers will always wish to complain about something). Other companies with very high speed filling lines may experience a much lower level as normal. It is useful to establish what the background `noise level' of complaint is for a particular brand or product so that it then becomes much easier to identify the start of a run of complaints and take early action as required.
8 Environmental issues in the manufacture of soft drinks and fruit juices Abstract: This chapter lists and answers key questions relating to environmental issues in the manufacture of soft drinks and fruit juices. It covers such issues as environmental legislation and regulation, waste management, effluent discharge and recycling. Key words: soft drinks, fruit juices, environmental issues, sustainability, waste management, recycling.
8.1 How do I find out about which regulations and consents apply to my business? In the UK the information on regulations has been placed on an official government website `NETREGS' which can be found at http://www.netregs.gov.uk. Further information on consents and guidelines for applications can be found on the websites of the Environment Agency in England and Wales (www.environment-agency.gov.uk) and the Scottish Environmental Protection Agency (SEPA) (www.sepa.org.uk). 8.2 What are the major sources of waste from my business? The types of waste will depend on the types of activities being carried out by the business. For fruit juice and soft drinks manufacturers who are diluting and blending juices, juice concentrates or syrups, there is likely to be little food waste produced, only traces from washing down after production and between products. The major sources of waste are likely to be packaging, either mis-filled or defective containers. The ingredients ± fruit juice, flavourings, additives, etc. ± are increasingly supplied in returnable containers, but packaging such as pallets,
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board, plastic shrink-wrap and glass are recyclable. Waste packaging such as mis-formed or broken bottles can also be recycled. Factories packing refillable glass or PET will create waste caustic detergent and labels as a result of the washing process. Increasing emphasis is being placed on the `carbon footprint' of food and drink products and producers may soon be required to state this on their labels. Such labelling would require an agreed standard format for its calculation. 8.3 Are all the necessary consents in place for me to discharge effluent? Discharges to sewer are controlled by the local authority sewerage company. A manufacturer must agree the levels of discharge with their own local responsible authority and keep within the agreed limits. In England and Wales any discharges into surface water are controlled by the Environment Agency and in Scotland by the Scottish Environmental Protection Agency (SEPA). In other countries manufacturers must seek the approval of the appropriate authority. Discharges in the UK are covered by Integrated Pollution Prevention and Control (IPPC). This required discharge permits to be obtained by 30 September 2005. The UK regulations, Pollution Prevention and Control (England & Wales) Regulations 2000, and parallel regulations for Scotland and Northern Ireland, implemented the EU Directive 96/61/EC. 8.4 Am I discarding valuable ingredients (such as sugar residues)? If so, can I recover all or part of them? In order to control costs it is essential to minimise the wastage of ingredients. Any reduction of ingredient losses contributes directly to profitability. Steps to reduce losses of concentrate, syrup or product can include minimising pipe runs or installation of a `pig' system. A `pig' system is a plug which is placed into the pipework at the end of a product run to `chase' the last of the product through the system. This both eliminates product loss and minimises the quantity of water needed to wash through between products. Reduction of washing and cleaning and modifications to production plant to reduce waste must not adversely affect hygiene and consequent product integrity. 8.5 Am I meeting my obligations under the Packaging Waste Regulations? In the UK it is a legal requirement that all producers and processors in the production chain must be registered with an officially recognised scheme such as VALPAK (www.valpak.co.uk). Not being registered will result in a fine. Producers who are unsure must check with the Environment Agency (in England and Wales) or SEPA (in Scotland). Details of the registration and guidelines are located on the EA and SEPA websites (see 8.1).
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8.6 Is there anything I can do to recycle any of my packaging components or to use recycled components? Many suppliers of ingredients, raw materials, packaging components, etc., already use packaging that is returnable and reusable. Packaging components such as pallets, shrink-wrap and board are either reusable or recyclable. Ensure that you use suppliers who use returnable or reusable components. Refer to publications such as `Recyclability by Design' from RECOUP (www.recoup.org.uk) or `A Guide to Eco-design' from Envirowise (www.envirowise.gov.uk). Increasingly, the suppliers of paper, board and other secondary packaging are using recycled materials. Glass, steel and aluminium have a long history of recycling, and recycling of plastic is increasing, though quantities are currently very limited. The UK's first recycling plant for food-grade PET opened in June 2008. 8.7 Can I use recycled PET? Recycled PET can be used for PET bottles but it must comply with the Plastic Materials in Contact with Food Regulations. The manufacturer or processor of the recycled PET is responsible for the quality and must ensure that it is food grade. Recycled PET (usually referred to as r-PET) is frequently blended with virgin PET but may be used at 100%. Two major drinks companies in the UK currently use 100% recycled PET for some of their bottles. The quality of PET slowly deteriorates as it is repeatedly recycled, therefore blending with virgin PET helps maintain quality. Some EU countries, e.g. France and Italy, have prohibited the use of recycled PET for drinks bottles, but EU legislation is currently being drafted to lay down standards in order to harmonise its use. 8.8 What is IPPC and does it relate to my business? IPPC is Integrated Pollution Prevention and Control and derives from the Pollution Prevention and Control (England & Wales) Regulations 2000 and parallel regulations for Scotland and Northern Ireland. It was enabled by EU Directive 96/61/EC and regulates processes to reduce the impact of all forms of pollution on the environment. It focuses on emissions to air, land and water, including waste disposal from regulated businesses. IPPC is monitored by the Environment Agency in England and Wales, by SEPA in Scotland and by the Environment and Heritage Service in Northern Ireland. All food and drink processors must obtain permits from the regulator. Initially the regulations applied only to emissions and waste but they have been extended to include energy use, noise, etc. Guidance for manufacturers can be found on the website www.envirowise.gov.uk.
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8.9 What is the Climate Change Levy and can I claim exemption? The Climate Change Levy (CCL) is applied directly to energy supplies to industry in the UK at a rate of 15%. It is included automatically in all energy bills to industry, but not those to private individuals. The climate change controls were implemented by EU Directives 2002/96/EC and 2003/108/EC. A discount of up to 80% of the levy can be obtained if companies participate in a climate change agreement. These agreements are recognised through an approved industry body such as a trade association. The industry agrees to target energy reduction over a period of years. The current climate change agreements were agreed in 2001 and so are due to expire shortly. The government will begin negotiations on the next round of targets imminently. Companies which are registered under IPPC are eligible to participate in their industry scheme. The scheme for food and drink producers in the UK is run by the Food and Drink Federation (FDF). At the time of writing the government targets for industry are being reviewed. If the industry as a whole meets its targets then members of that industry's scheme qualify for a discount of up to 80% of the levy. 8.10 Is my business affected by WEEE? The Waste Electrical and Electronic Equipment Regulations (WEEE) are only applicable to producers and suppliers of electronic and electrical equipment and therefore have little impact upon soft drink manufacturers. The regulations do, however, impact upon dispense (draft drinks) equipment such as carbonator/ coolers and to vending equipment. The regulations came into effect in the UK on 2 January 2005, but they have since been amended by regulations SI 2006 3289 and SI 2007 3454. Guidance to industry on compliance with the regulations can be found on the website of the Department of Business Enterprise and Regulatory Reform (BERR) at www.berr.gov.uk. There are a number of producer compliance schemes in operation and a list can also be found on the BERR website. 8.11 Do my containers have to be recyclable? The Packaging Essential Requirements Regulations require recyclability but firstly the packaging must be functional. Functionality is the primary essential requirement. All forms of soft drink packaging, i.e. glass, plastic, cans and cartons, are deemed to be recyclable. However, manufacturers should aim to maximise the ease with which their packaging can be recycled by, for example, not mixing and binding different types of plastic into one package. 8.12 Are coloured plastics recyclable? Technically, coloured PET could be recycled but from a practical viewpoint it is much more difficult than recycling colourless PET, which retains a higher value
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as it can be recycled in a closed loop back into bottles. Coloured PET is recycled into other products. It is not practical to separate and recycle all the different colours of PET so they are retained as a mixture and are recycled only where the colour is unimportant. Such recycled mixed PET has a much lower value than colourless PET which can be reused for container manufacture.
9 Regulatory issues relating to soft drinks and fruit juices Abstract: This chapter lists and answers key questions about regulatory issues relating to soft drinks and fruit juices. It covers ways of ensuring compliance with legislation, labelling of ingredients (including QUID), nutritional and allergen labelling. Key words: soft drinks, fruit juices, regulation, labelling, QUID.
9.1 How much information should be available in product formulations? Formulation data is key, not only to the manufacture of a consistent product, but also to the provision of essential information such as composition, label data, to confirmation of compliance with statutory requirements, and in many companies the costing basis and stock utilisation. Many manufacturers use a standard formula base of 1000 kg (or 1000 litres) of product, which is convenient for the calculation of percentage composition and as the basis for larger or smaller batch sizes. Companies that only ever produce one size of batch will often find it more convenient to use their standard production batch size as the base formula. Whatever standard batch size is used, it should be possible for individual batch sheets to be generated for the purpose of production directly from the master standard formula, preferably by electronic means and thus avoiding the risk of human error. Calculation of the composition of a product is the basis for determining the list of ingredients in descending order and will also show levels of specific ingredients such as additives, where there may be a maximum statutory limit or where the amount of fruit juice or whole fruit is required to be declared. Retention of product formulations can be used as a valuable archive in case of queries or to enable a company to return to a previously used formulation. Current master formulations should be part of the quality assurance system
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within an organisation and should show, in addition to quantities and specification references of ingredients used, process control standards and tolerances, composition, compliance with statutes, shelf-life data, sample labels and any other data required. It is normal for the product formulations to be linked to the commercial functions to facilitate costing and stock usage. It is essential that access to the formulas, whether held in hard copy or in electronic format, is strictly limited and some form of double key control should be in place for new formulas or any changes. 9.2 How can compliance with legislation in markets other than that for which the product was originally designed be confirmed, and how can such information be kept up to date? Products designed to be sold in a large single market such as the countries of the European Union are often acceptable within many other markets in the world. However, even then there are differences of labelling, which additives may be used and in what quantities, the level of a particular component required to sustain a particular product description, and other minor changes that may become necessary. It is likely to be particularly important to check legislative needs for soft drinks that are more likely to incorporate additives and a variety of ingredients. However, even products such as fruit juices may not necessarily be exempt from possible local legislative demands, particularly if they are reconstituted from concentrates. There may be local minimum standards for solids content (Brix level) although these may arise from local codes of practice rather than legislation. Large companies, particularly those that have multinational markets, often maintain an in-house facility to keep abreast of the different requirements of target markets. Small and medium-sized companies will probably need to use the facilities of an external organisation with a competent overseas legislation department in order to ensure legislative compliance (see 7.2.4). Other useful sources of information include government trade missions, Chambers of Commerce, Trade Associations and business agents operating in the target market. 9.3 How can the fruit or juice content of a product be calculated for the purpose of declaring the QUID value or for confirmation of a claim? The QUID (quantitative ingredient declaration value) is required in the UK to permit consumers to compare products in respect of their comparative juice or fruit content and consequent value for money. In the event that fruit or juice is added as a single strength ingredient (i.e. the ingredient has not been concentrated) the calculation is straightforward. As an example, 1000 litres of a juice drink contains 120 litres of an unconcentrated fruit juice; the juice content is then (120/1000) 100% 12%.
Regulatory issues relating to soft drinks and fruit juices
169
The situation becomes more complicated when the juice or fruit component is added in the form of a concentrate. To obtain the degree of concentration of the concentrate, the initial solids level in the juice (usually declared as ëBrix) should ideally be known. Since in most situations this information is not available, the calculation is performed on the basis of the target Brix of the juice after dilution. As an example, the fruit content of 100 kg of orange juice concentrate of 66ëBrix is required to be calculated for an addition into a juice drink. The target Brix for diluted orange juice is taken as 11.2ë. Thus (66/11.2) 100 589.3 kg of single strength juice. For most applications, the amount is required in volumetric quantity, so the quantity in kilograms needs to be divided by the density of juice at 11.2ë (1.043). Thus 100 kg of orange juice concentrate at 66ëBrix is equivalent to (66/11.2) (100/1.043) 565 litres of single strength orange juice at 11.2ëBrix. Determining the amount of fruit or juice in a product by analysis is difficult and a number of different approaches have been taken. These have involved assessing the ash content, levels of potassium ions, phosphorus content, total level of free nitrogen by measuring the formol value, amino acids and other compounds. If only a simple approach is taken to determine fruit or juice content, it is easy for an unscrupulous supplier to circumvent the method of analysis by adding amounts of potassium, phosphorus and ammonium salts. Other methods such as the amino acid profiles have been developed to try to give more reliability to the testing. In general, however, analysis can only give an estimate of the fruit or juice content, particularly when mixtures of juice are added. Specific juices may have a characteristic marker (e.g. quinic acid in cranberry juice) which can be a useful indicator. Further reading is available on this topic ± see, for example, the booklet produced by the British Soft Drinks Association. 9.4 How important is it to be able to access historical formulas? There is no obligation as such on manufacturers in most countries to maintain details of historical formulations, although it would be expected that details of all current formulations should be readily available at least within the shelf-life of the last batch made, to meet traceability obligations. There is, however, an expectation in many countries that relevant documentation should be held for a period of some years (typically seven) in case of enquiry by official bodies. Aside from any other reason, most manufacturers will maintain a detailed record of past formulations so that earlier products can be recreated if required. Marketing and manufacture of soft drinks is often a cyclical process with the starting product being gradually eroded in quality or quantity of ingredients to maintain stable pricing or profit margins in the market until it is decided that the original quality product should be recreated and relaunched. Development departments will also wish to maintain detailed records, for example to track the use of specific ingredients, to identify any longterm trends and to access data in case of particular problems arising that may be linked to historical usage of a particular ingredient.
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9.5 Are current product labels accurate, up to date and legal? As a minimum, soft drink and fruit juice beverage labels in the UK must carry the following basic information: · · · · · · · · · ·
The name of the product (i.e. its appropriate designation) A list of ingredients in descending order by weight The appropriate durability indication Any special storage conditions or conditions of use The name or business name and an address or registered office of the manufacturer and/or the packer or seller established in the EU Particulars of the provenance or origin of the product if required Instructions for use if it would be difficult to make appropriate use of the product without such information The contents and e-mark Full nutritional data if vitamins and minerals are added as ingredients (irrespective of any claim) Allergen information if relevant.
However, labels are much more than the basic statutory declaration and are used to attract consumers, display the brand, generally inform consumers about nutrition and, in many cases, provide much more information. The basic information on a label, particularly the appropriate designation and list of ingredients, are generated from the product master formula and must coincide with what is in the manufactured product. Apparent small changes in a formulation can alter the content or order of listed ingredients and thus render a label technically invalid. There needs to be close liaison between marketing and development departments to ensure accurate and up-to-date information. This is especially important when product formulation changes are being planned. For beverage manufacturers the additional information needed will include QUID data and nutritional values as well as any claims for vitamin or mineral content. Requirements for weights and measures are covered in the United Kingdom by the Weights and Measures (Packaged Goods) Regulations 2006 SI No. 659 and corresponding guidance notes. 9.6 Should the local Trading Standards Department (or other relevant enforcement authority) be involved in approving product labels? In the United Kingdom, enforcement of food labels is the responsibility of Trading Standards. This is a function of county councils rather than district councils except where the local body is a unitary authority. It is recommended that all product labels are sent for comment to the Trading Standards body, although the final responsibility for the product label and its content rests with the manufacturer. Once a label has been approved by the enforcement body, any subsequent complaints from other enforcement agencies may be fielded by the Trading Standards Department in the area in which the manufacturer is located.
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This is known as the `Home Authority' principle, although there is no mandatory requirement on the local authority to carry out this function. Such approval does not guarantee freedom from further action by other bodies but it is much less likely. Some Trading Standards officers are more inclined to allow additional information regarding product descriptions and claims than others, but all the basic information that was set out in 9.5 must be present. It is essential to ensure that any nutritional claims (e.g. for the presence of vitamin C) are capable of being sustainable throughout the stated shelf-life of the product. Such claims are not normally challenged at the time of label approval but are likely to be tested by officers carrying out random sampling followed by analysis (see 9.7). 9.7 How can nutritional claims be sustained, and how should nutritional data be obtained? The claims most usually made for soft drinks and fruit juices and nectars are those for vitamins (particularly vitamin C) and minerals. Sustaining a claim for a mineral content such as calcium presents no particular difficulties, as minerals are not destroyed on storage and can be determined by analytical measurements. A small overaddition (5±10%) is usually made to ensure claims can be sustained. The most likely difficulty to be encountered is that a mineral such as calcium may be selectively taken up into a particular ingredient such as degraded pectin. It will, however, still be present in the product as a whole and usually without any reduction in its bioavailability. Vitamins are, however, notoriously labile and since vitamin C is often added as much for its antioxidant property as its nutritional value, due consideration must be made for chemical degradation. Some manufacturers work on a rule of thumb principle of, for example, adding double the amount to be claimed and then refining the addition on the experience of analysis during shelf storage. Others know the likely performance of product/packaging interactions in fine detail and can make a more informed overaddition. General nutritional data for declaration on the pack is normally provided on the basis of calculations from the ingredients of the product. Some beverage labels provide no more than the `big 4', i.e. energy value, carbohydrate, protein and fat contents per 100 ml and per pack size. Standard values for calculating these components are readily available from data handbooks such as McCance and Widdowson's The Composition of Foods (FSA, 2002). It is often necessary for nutritional values for key ingredients to be obtained from suppliers. It should be remembered that energy values must include contributions from organic acids, alcohol and fibre. Full nutritional data must be provided if any vitamins or minerals are added.
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9.8 What does a responsible manufacturer have to do to keep up to date with statutory requirements? This is an absolute requirement for any company but the way in which it is achieved is likely to be determined by the size of the company. Some manufacturers have legal departments that are able to maintain a monitoring brief on all possible areas of statutory impact on the company, but many have to rely on other sources. For companies that specialise in the production of soft drinks or fruit juices, it is useful to obtain or renew membership of an appropriate trade organisation (in the United Kingdom one example is the British Soft Drinks Association). Most major economies have dedicated trade organisations covering soft drinks and fruit juices. Other organisations with considerable expertise, not simply in beverages but in many other areas of food legislation, include Leatherhead Food International and the Campden and Chorleywood Food Research Organisation (see 7.2.4). Some changes are well forecast by government departments and local government with whom food manufacturers have to register, but it remains the responsibility of the individual company to ensure compliance. Other useful sources include ingredient and equipment suppliers. For non-industry statutory information, local Chambers of Commerce or Business Link are also good sources of forthcoming legislation that are likely to impact on all manufacturers. 9.9 Does allergen labelling apply to soft drinks? Food allergy and intolerance are thought to affect about two million people in the United Kingdom and much larger numbers in Europe and elsewhere in the world. Symptoms range from being relatively mild to life-threatening and although most children grow out of it there is no cure for food allergy or intolerance. In consequence the UK government has introduced regulations requiring manufacturers to label any product (including soft drinks) containing one or more of the allergens identified in the relevant regulations (EU Directive 89/2003EC) and local enabling regulations. The allergens that must be included in any label are as follows: · · · · · · · · · · · ·
Cereals containing gluten Crustaceans Eggs Fish Peanuts Nuts Soybeans Milk Celery Mustard Sesame Sulphur dioxide at levels above 10 mg/kg or 10 mg/litre.
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Of these the most likely allergen that may be present in beverages is sulphur dioxide. In the UK this is no longer permitted as a general preservative and the most likely occurrence of this preservative is in concentrated drinks (i.e. `squashes, cordials and whole fruit drinks') where it may be used and has been carried over from preserved fruit concentrates. It is therefore essential for manufacturers of such products to check levels of sulphur dioxide and indicate the presence of the allergen accordingly. This may involve obtaining appropriate disclosures from ingredient suppliers. 9.10 What are the main statutory requirements with which a beverages manufacturer must comply in the United Kingdom? There is a very wide range of legislation that must be complied with by any business entity and it is beyond the scope of this book to attempt to cover the topic. All businesses should take appropriate advice from a suitably qualified lawyer to ensure compliance with all relevant law. In addition to any other legislative compliance, in the United Kingdom there are specific requirements under the provisions of the Food Safety Act 1990 and related regulations that food manufacturers should be particularly aware of. They apply to all commercial activities relating to food (for which there is a wide definition including drink), irrespective of the size of the operation. The Act provides wide powers of enforcement. One requirement is for the registration of food businesses, which is normally handled by the local Environmental Health Department. Businesses that are unfamiliar with Food Act and hygiene regulations will usually find the local Environmental Health officers an excellent source of information and sometimes training in key areas. Registration of a new food-related business often provides access to a wide range of potential assistance. In addition to compliance with statutes in the United Kingdom (or whatever the local country regulations demand) there needs to be a wide understanding of any relevant codes of practice (such as the minimum Brix level for reconstituted fruit juices) and quality standards such as the British Retail Consortium Technical or ISO Standards. Trade associations and other well-respected sources of information normally provide excellent guidance on such matters. It should be noted that the minimum Brix levels for fruit juices, currently used on a code of practice basis using the AIJN recommendations, are likely to become statutory requirements throughout Europe during 2009. The current AIJN values for minimum Brix levels for juice are likely to be accepted.
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Soft drink and fruit juice problems solved
9.11 What does a manufacturer need to be aware of when wishing to make nutritional claims for a product as listed in EU Regulation 1924/2006? The claims that may be made under current UK food labelling legislation are limited and must not relate to any tonic properties (other than the specific regulation that allows `Indian Tonic Water' or `Quinine Tonic Water' to be so called). The above-mentioned regulations permit a derogation for Tonic Water. In particular, no claims may be made to the effect that a food has the property of preventing, treating or curing any human disease and no reference may be made to such a property. This is an area of potential difficulty for companies that wish to develop products in the functional beverage or nutraceutical category. Generally, then, claims that are permitted relate to the following: · · · · · ·
Foods for specific nutritional purposes (e.g. energy drinks) Foods with reduced or low energy values Claims for a specific protein, vitamin or mineral content A claim relating to the presence or absence of cholesterol A general nutritional claim Claims that depend on another food.
Specific claims for vitamins and minerals, which are limited to those listed in the regulations, must contain the amount claimed throughout the life of the product. General nutritional claims for soft drinks and fruit juices are likely to be limited to energy, protein, carbohydrate (which may be subdivided into sugars, polyols and starch) and fat. For some products other claims such as sodium or fibre content may be relevant. There are prescribed contents for the use of nutritional labels which must be followed. For general nutritional information, the amounts given shall be for 100 grams or 100 millilitres and in a quantified serving, and are given as averages based on one or more of the following: · The manufacturer's analysis · A calculation from generally accepted data · A calculation from the actual average values of the ingredients used. There are other detailed requirements which need to be considered. As far as claims for benefits that may be delivered by a particular product are concerned, it is difficult to provide general indications unless the claim is for delivering energy or hydration and such matters should be discussed with the appropriate enforcement body (Trading Standards Departments in the UK). Any claim relating to a specific nutrient must be for a `significant amount' of the nutrient, which is at least 15% of the RDA per 100 g or 100 ml of the product, unless the product is packed as a single serving when the amount must be found in that serving.
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9.12 How is the nutritional value of a product calculated? The European Directive on Nutritional Labelling of Foodstuffs sets out rules and indicates the way such data is presented on food labels (90/496/EEC). As indicated in 9.7 and 9.11, the UK Food Labelling Regulations 1996, which include regulations based on the above directive, indicate three means of determining the nutritional value of a food or beverage, as follows: · The manufacturer's analysis · A calculation from generally accepted data · A calculation from the actual average values of the ingredients used. The analysis is usually based on obtaining quantities for the key components (carbohydrates, proteins, fats, etc.) followed by the appropriate calculation using recommended calorific values. An alternative approach for determining overall energy values would be to obtain the actual energy value (e.g. by bomb calorimetry), although this is probably little used. Most nutritional values are determined by calculation from base data from one of the three methods outlined above. Key differences between the Directive and the previous way in which these values were calculated in the UK are given in the following two tables: As required by the Traditional method EC Directive Protein
N content 6.25
Total carbohydrates Sugars Starch
As the actual weight of the carbohydrate
Dairy N 6.38 Cereals N 5.7 Specific factors for certain foods All other foods N 6.25 After conversion to monosaccharides
Energy values per gram (previous values in brackets)
kJ
kcal
Protein Carbohydrate Fat Alcohol All organic acids Sorbitol and other polyols Fibre
17 (17) 17 (16) 37 (37) 29 (29) 13 (0) 10 (16) 8.5 (±)
4 (4) 4 (3.75) 9 (9) 7 (7) 3 (0) 2.4 (3.75) 2 (±)
Source: Food labelling data based on McCance and Widdowson's The Composition of Foods (FSA 2002).
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9.13 Are there any special health and safety issues that relate to soft drinks manufacture? Health and safety is the responsibility of everyone in an organisation and there are a wide range of issues that need to be assessed in any operation. In any company there needs to be a full assessment of all the health and safety risks that are present and appropriate steps need to be taken to ensure the safety of workers, management and visitors to any site. Beverage plants do, however, present some special hazards which may not occur in other situations and any assessment should include special consideration of the following issues: · Noise Much packaging machinery is very noisy, especially when glass bottles and cans are involved, and ear protection is almost always essential. · Eye protection This is essential for all present in the plant, particularly when glass packaging is employed. Even where other forms of packaging are used, fragments of packaging or product splashes can occur and are capable of causing serious eye damage. Particular concern should be paid to cleaning chemicals, and any pipework carrying caustic, acidic or hot solutions should be routed well away from pedestrian walkways and regularly checked for leaks. · Foot protection All present in beverage plants should use protective footwear to minimise the risk of damage from sharp fragments and dropped items. This is often a particular concern where temporary staff are employed and not provided with necessary protection. · High-speed machinery Packaging plant usually involves high-speed rotating or reciprocating machinery and must be adequately protected with suitable interlock protection to prevent operator or engineer access whilst there is any risk of the plant running. Most modern machinery includes such features but older or reconditioned plant may be less well protected. · Pressure vessels Plant that is packing carbonated beverages requires the storage and distribution of carbon dioxide gas compressed to high pressure, and adequate protection must be provided in case of bursting. This is most likely to occur when bottles are filled and the machinery must be able to contain burst bottles and their contents. The above are only examples of the potential hazards in a beverage plant and, as indicated above, a full health and safety risk assessment must be carried out for each plant.
References and further reading
P.R. Ashurst (2005) Chemistry and Technology of Soft Drinks and Fruit Juices, 2nd Edn, Blackwell Publishing, Oxford, ISBN 1 4051 2286 2. S. BluÈml and S. Fischer (2004) Manual of Filling Technology: The theory and practice of filling liquid products, Woodhead Publishing Limited, Cambridge, ISBN 3 89947 197 0. D.W. Brooks and G.A. Giles (2002) PET Packaging Technology, Blackwell, Oxford, ISBN 0849397863. EC (2008) Flavouring Regulations 1334/2008/EC. EU Commission Guidance on HACCP http://ec.europa.eu/food/food/biosafety/ hygienelegislation/guidance_doc_haccp_en.pd EU (1990) Directive 90/220/EC. EU (1997) Novel Food Regulations 258/97/EC. EU (2000) Labelling Directive 2000/67/EC. EU (2002) Directive 2002/67/EC. EU (2004) Food Hygiene Legislation 852/2004/EC. EU (2009) Directive 2009/54/EC. Guidance on Bottled Water Regulations 2007 http://www.food.gov.uk/foodindustry/ guidancenotes/foodguid/waterguidance Guidance on Clear Food Labelling http://www.food.gov.uk/multimedia/pdfs/ clearfoodlabelling.pdf Guidance on Country of Origin Labelling http://www.food.gov.uk/multimedia/pdfs/ originlabellingguidance.pdf Guidance on Materials in Contact with Food Legislation http://www.food.gov.uk/ multimedia/pdfs/foodcontguide0903rev1 Guidance on Food Hygiene Legislation http://www.food.gov.uk/foodindustry/ guidancenotes/hygguid/fhlguidance/ FSA (2002) McCance and Widdowson's The Composition of Foods, 6th Edn, Royal Society of Chemistry, Cambridge.
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HMSO (1996) The Food Labelling Regulations 1996, SI 1499 as amended. HMSO (2006) The Weights and Measures (Packaged Goods) Regulation 2006, SI 659. D. Man (2002) Shelf Life, Blackwell, Oxford, ISBN 0632056746. P. Paquin (2009) Functional and Speciality Beverage Technology, Woodhead Publishing Limited, Cambridge, ISBN 978 1 85469 342 8. D.A.G. Senior and N. Dege (2005) Technology of Bottled Water, 2nd Edn, WileyBlackwell, Oxford, ISBN 9781405120388. M. Shachman (2004) The Soft Drinks Companion, CRC Press, Boca Raton, ISBN 0849327261. N. Starbard (2008) Beverage Industry Microfiltration, Wiley-Blackwell, Oxford, ISBN 9780813812717. D. Steen and P.R. Ashurst (2006) Carbonated Soft Drinks: Formulation and manufacture, Blackwell Publishing, Oxford, ISBN 1 4051 3435 6. T.A. Turner (2001) Can Making for Can Fillers, Blackwell, Oxford, ISBN 1841272205.
INDEX
Index Terms
Links
A abstraction licenses
122
123
acetaldehyde
127
130
Acetobacter
104
110
activated alumina
117
125
aeration
125
air supply
111
Alicyclobacillus
111
Alicyclobacillus acidoterrestris
5
allergen labelling
172
aluminium
105
amino acid profiles
169
antifoam
59
Arrhenius equation
15
ascorbic acid
86
aseptic packing automation
110
111
87
97
106 69
B bar code system
151
batch codes
149
benzene
128
This page has been reformatted by Knovel to provide easier navigation.
138
Index Terms
Links
benzoates
86
benzoic acid
87
91
best before date
114
140
borehole
122
actions to be taken if water quality drops
124
intermittent extraction of water
124
needed information
122
protection
122
quality consistency
123
bottled waters
117
carbon dioxide component specification legislation
129 117
allowable additional ingredients
121
discharge consents
121
labelling
119
required licenses
120
testing regime
120
UK legislation
117
quality issues
127
appearance defects
127
carbon dioxide quality
128
closures and packaging materials
130
microbial content
128
shelf-life
129
taints sources
127
storage and distribution 130 This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
bottled waters (Cont.) water extraction
122
water treatment and bottling
125
special precautions in water bottling plant water sterilisation
126 126
bottles
141
British Fruit Juice Association
159
British Retail Consortium Technical
173
British Soft Drinks Association
159
169
172
24
25
29
31
32
33
38
62
85
89
168
169
Brix
173 Brix Acid Ratio
56
85
C calcium
171
calcium ions
97
Campden and Chorleywood Food Research Organisation
172
Campden BRI
160
cans
108 defects
139
risk of metal pickup
136
caramel
47
141
86
This page has been reformatted by Knovel to provide easier navigation.
Index Terms carbohydrate sweeteners
Links 29
effect in production and process control
31
fruit extract labelling
32
product stability
31
special technical and process requirements for handling
32
specifications for carbohydrates
33
for use in soft drinks
29
fructose syrup
30
glucose syrup
29
high fructose glucose syrup
29
invert sugar
29
legislation
30
specialist carbohydrates
30
sugar
29
vs sucrose
30
carbon dioxide
62
carbon footprint
163
carbonation
58
carbonation retention
135
cartons
137
catchment area management systems
120
chemical contamination
108
119
108
109
95
158
chlorine
103
128
chlorine treatment
127
chlorophytes
130
chromatographic fingerprinting 62 This page has been reformatted by Knovel to provide easier navigation.
121
Index Terms citric acid
Links 86
clear labelling
141
Climate Change Levy (CCL)
165
Closure Manufacturers Association
134
closure selection
134
colour fading
97
coloured PET
165
colourings
43
labeling
45
selection
43
stability
46
Combibloc
103
commercially sterile
111
complaint report summaries
161
88
45
45
108
138
consumer complaints about soft drinks and fruit juices
153
recording and handling consumer complaints
153
classification
154
handling system
153
justification of complaints
155
product recall
156
response time and attitude
156
traceability systems and crisis management
157
complaint report summaries
161
crisis management team
158
expert assistance 158 This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
consumer complaints (Cont.) informing enforcement authorities
160
public relations advisor
160
system effectiveness
157
consumer reactions
17
assessment
17
market research outsourcing
18
sales volume prediction
18
cost constraints
7
accurate costings and financial evaluations
8
impact assessment
8
initial product concept
7
production line
9
selling price
9
crisis management team
158
Cryptosporidium
110
128
D dairy products
68
decantation
125
deionisation
125
Department of Health
159
dimethyl dicarbonate
91
Director of Public Health
159
DMDC
66
drop test
135
This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
duo-trio testing
101
E electronic sniffer device
141
Elopak
138
emulsion stability
99
Environment Agency in England and Wales
162
163
164
Environment and Heritage Service in Northern Ireland
164
Environmental Health Department
159
EU Directive 89/2003 EC
172
EU Directive 96/61/EC
163
EU Directive 2002/96/EC
165
EU Directive 2003/40/EC
118
EU Directive 2003/108/EC
165
164
EU Directives on Sweeteners, Colours and Miscellaneous Additives EU Hygiene Regulations 2004
6 149
EU Regulation 852/2004
80
EU Regulation 1924/2006
174
European Directive on Nutritional Labelling of Foodstuffs
175
European Food Standards Agency
136
excess wax/oil test
135
This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
F factory gate pricing systems
151
FIFO system
151
filling systems
74
clean-in-place system
75
product quality
74
quality check
75
temperature
76
filtration
125
flash pasteurisation
74
92
flavour character
89
deterioration affecting factors
99
chemical factors
100
microbiological factors
100
physical factors
99
influence of packaging on deterioration
103
ingredients that cause flavour problems
101
microbiological infections as cause of deterioration
104
origin of flavour taint
102
removal of chlorine in process water
103
sensory tests used to evaluate changes
101
flavoured waters
130
This page has been reformatted by Knovel to provide easier navigation.
Index Terms flavourings
Links 38
approval for novel ingredients
43
assessment
39
availability
42
interaction with other ingredients
41
labelling
42
product stability
40
shelf-life
39
types
38
flip lid closures
138
floc formation
84
fobbing
77
Food Act and hygiene regulations
173
Food and Drink Federation
165
Food (Lot Marking) Regulations 1996 SI 1502
149
Food Safety Act 1990
173
Food Standards Agency
157
foreign body contamination form-fill-seal containers
159
79 142
formulation history
94
fruit components
23
concentration
24
exotic fruits
26
fruit material authenticity
28
juices, comminutes, purees, and extract
23
special processing for packed fruit juice and products 24 This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
fruit components (Cont.) specification
25
sugar-free label
27
sugar range/levels of common juices
27
fruit juices environmental issues in manufacture
162
handling consumer complaints
153
ingredients
20
carbohydrate sweeteners
29
colourings
43
flavourings
38
fruit components
23
intense sweeteners
33
miscellaneous ingredients
56
nutraceutical ingredients
53
preservatives
48
water
20
manufacture
45
60
filling operations and related issues
74
finished product storage
81
ingredient sourcing and storage
60
mixing, compounding and related problems
65
pasteurisation, homogenisation and related issues secondary packing
70 80
This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
fruit juices (Cont.) packaging, storage and distribution
132
distribution problems
150
packaging defects
138
packaging selection
132
post-filling defects
145
problems during filling and packaging operations storage conditions product development quality issues in processing
141 148 1 83
colour and appearance changes
96
flavour deterioration
99
ingredient interactions
86
ingredient quality
83
ingredient specifications
88
microbiological problems
109
packaging interactions
104
problems during manufacture and safety issues shelf-life issues regulatory issues fruit pulp
90 114 167 98
G Giardia
128
glass
108
This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
glass bottles
141
defects
138
146
problems associated with use of returnable glass bottles greensand-type filters
136 117
125
80
93
H Hazard Analysis Critical Control Point (HACCP) Health Protection Agency
159
high density polyethylene
133
historical formula
169
‘ome Authority’ principle
171
homogenise
72
hot filling
72
hydrogen peroxide hypertonic drink hypochlorite
121
106 6 126
hypotonic drink
6
I impact test
135
in-pack pasteurisation Indian Tonic Water
72 174
Integrated Pollution Prevention and Control (IPPC)
163
164
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Index Terms
Links
intense sweeteners
33
aspartame
36
blending
37
cyclamate
37
natural sweeteners
36
selection
33
usage rates stability
34 35
taste profiles sweetness values xylitol use
35 38
International Society of Beverage Associations
87
iron (steel)
105
ISO 9001
63
ISO 9002
63
ISO 14000
63
ISO 28000
63
isotonic drink
6
L Lactobacillus
104
Leatherhead Food International
160
172
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Index Terms
Links
M manufacturing
12
outsourcing
12
principal limitations
12
production facility modification
13
small-scale trials
12
special handling facility
13
test plant data scale up
14
marketing brief
5
detailed product information
5
preparation
5
regulations for sports drinks
6
review
7
special regulations for infant products
6
tooth-friendly drinks
7
metal contamination microbiological contamination microbiological problems
159 95
102
109
bacterial infections
113
best plastic to pack still drinks
108
mould contamination
113
pathogenic organism contamination
110
quarantine storage
112
signs of microbial contamination
111
sources of microbial contamination
111
spoilage organisms of concern
109
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Index Terms
Links
microbiological problems (Cont.) susceptibility of soft drinks to microbiological spoilage
109
Zygosaccharomyces bailii contamination microbiological tests mineral salts
113 4
140
121
N natural mineral water
117
NETREGS
162
Novel Foods Regulations
26
nutraceuticals
53
antioxidants
55
labelling
55
other ingredients
55
vitamins and minerals
54
nutritional claims
171
nutritional data
171
nutritional value
175
118
125
174
O oil rings
96
oily film
67
one-up-one-down principle
94
outsourcing
61
oxygenation
125
149
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Index Terms ozone
Links 125
126
10
80
P packaging defects
138
design
11
interactions
104
aseptic packs
106
cans
105
detailed specifications
106
flexible packaging
106
glass packaging
105
major packaging problems
107
plastic packaging
104
preferred packaging
10
product concept
10
production and cost
10
selection
132
shelf-life in PET packages
108
Packaging Essential Requirements Regulations Packaging Waste Regulations
165 163
PARNUTS Framework Directive (89/398/EC)
6
pasteurisation
70
pectinesterase enzyme
83
pectins
97
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Index Terms
Links
Penicillium
110
Penicillium roqueforti peracetic acid
5
110
106
PET, see polyethylene terephthalate physical contamination
95
pig system
163
pin holing
105
plastic bottles
141
159
139
Plastic Materials in Contact with Food Regulations plug formation
164 98
Pollution Prevention and Control Regulations 2000
163
polycarbonate
133
polyethylene
108
polyethylene naphthalate
133
polyethylene terephthalate
108
polygalacturonic acids
133
164
97
polylactic acid
133
polyolefins
108
polyphenolic compounds
164
86
polystyrene
133
polyvinyl chloride
109
polyvinyl dichloride
108
post-filling defects
145
pouches
106
133
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Index Terms preservatives
Links 48
benzoic acid
52
DMDC
51
selection
49
pressure test
91
135
product development new soft drinks and fruit juices consumer reactions
1 17
cost constraints
7
initial issues
1
manufacturing issues
12
marketing brief
5
packaging issues
10
shelf-life
14
product formulation
94
product labels
170
product recall
156
167
160
product storage ideal conditions
81
quarantine
82
Pseudomonas aeruginosa
128
public relations advisor
160
Q quantitative ingredient declaration (QUID) value
168
quarantine storage
112
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Index Terms
Links
quaternary ammonium salts
126
Quinine Tonic Water
174
R Reading Scientific Services Ltd
160
recall
149
record keeping
93
recycled PET
164
recycling
164
Regulation 852/2004
157
removal torque test
135
reverse osmosis
125
165
S Saccharomyces cerevisiae
109
Scottish Environmental Protection Agency
162
163
scuffing
105
136
secondary packaging
146
selling price Sensory Dimensions shelf-life
164
9 160 14
accurate prediction
114
assessment methods
15
business plan
16
definition
114
effect of packaging
116
114
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Index Terms
Links
shelf-life (Cont.) main affecting factors
114
monitoring
115
need for long shelf-life
115
prediction
14
regular assessment
17
small pilot plant
15
sniffer device
100
snifting
77
sodium benzoate
88
sodium metabisulphite solution
91
soft drinks environmental issues in manufacture
162
handling consumer complaints
153
ingredients
20
manufacture
60
filling operations and related issues
74
finished product storage
81
ingredient sourcing and storage
60
mixing, compounding and related problems
65
pasteurisation, homogenisation and related issues secondary packing
70 80
packaging, storage and distribution
132
appropriate carbonation levels
144
distribution problems
150
packaging defects 138 This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
soft drinks (Cont.) packaging selection
132
post-filling defects
145
problems during filling and packaging operations storage conditions product development quality issues in processing
141 148 1 83
colour and appearance changes
96
flavour deterioration
99
ingredient interactions
86
ingredient quality
83
ingredient specifications
88
microbiological problems
109
packaging interactions
104
problems during manufacture and safety issues shelf-life issues regulatory issues
90 114 167
sorbates
86
sorbic acid
91
sports caps
130
sports closures
138
spring water
118
stack-burn phenomenon
144
stevia stress corrosion
36 147
sucrose acetate isobutyrate 99 This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
sulphur dioxide
86
91
97
103
127
130
159
173 supplier contract
64
T table water
118
tail end blow off (TEBO)
147
taints
102
tamper evidence
135
tannins
86
TEBO, see tail end blow off TetraPak
103
thaumatin
36
thermal pasteurisation
71
three packers rule
78
tolerable negative error
78
tooth-friendly drinks top load vent test
108
73
7 135
traceability
94
trade recall
161
Trading Standards Department
170
triangle testing
101
tunnel pasteurisation
92
turbidity meters
96
94
145
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Index Terms
Links
U UK Bottled Water Regulations 2007
121
UK Food Labelling Regulations 1996
175
UK Food Safety Act 1990 unique selling point UV irradiation
79 1 127
V VALPAK
163
Velcorin
91
vitamin C
171
W Waste Electrical and Electronic Equipment Regulations waste sources water
165 162 20
‘lavoured water’ classification
23
ideal specification
22
natural mineral water or spring water
22
quality on softdrinks
20
calcium levels
21
chlorine
21
hardness
21
iron
21
nitrate levels
21
This page has been reformatted by Knovel to provide easier navigation.
Index Terms
Links
water (Cont.) sunlight
21
testing frequency
22
water treatment in soft drinks/fruit juice processing plant
21
water cloudiness
127
water supply
112
Weights and Measures (Packaged Goods) Regulations 2006 SI No. 659 withdrawal wood rosin ester
170 149 99
Z Zygosaccharomyces bailii
5
110
113
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