Aseptic Processing and Packaging of Particulate Foods Aseptic Processing and Packaging ofParticulate Foods

Edited Ьу

EDWARD М. А. WILLHOFT Principal Epsom Teclmical Group Services Epsom Surrey

SPRINGER-SCIENCE+BUSINESSm МEDIA, В.У First edition 1993 © Springer Science+Business Media Dordrecllt 1993 Originally published Ьу Chapman & НаН in 1993 Softcover reprint ofthe hardcover 1st edition 1993 Typeset in 10/12 р! Times New Roman Ьу DSC Corporation, Comwall, England

ISBN 978-1-4613-6361-3 ISBN 978-1-4615-3112-8 (eBook) DOI 10.1007/978-1-4615-3112-8 Apart from апу fair dealing for the pиrposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication тау по! Ье reproduced, stored, or transmitted, in апу form or Ьу апу means, without the prior permission in writing ofthe publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued Ьу the Copyright Licensing Agency in the UK, or in accordance with the terms oflicences issued Ьу the appropriate Reproduction Rights Organization outside the UK Enquiries conceming reproduction outside the terms stated here should Ье sent to the publishers а! the Glasgow address printed оп this page. The publisher makes по representation, express or implied, with regard to the accuracy ofthe information contained in this book and саШlOt ассер! апу legal responsibility or liability for апу errors or omissions that тау Ье made.

А catalogue record for this book is available from the British Library Preface

Publications in food technology proliferate; however, noticeable by its absence of coverage is the subject of processing and packaging of particulates in foods. Recent years have seen significant advances which will almost certainly result in substitution of existing and conventional retorting. In addition, when com• bined with high temperature/short time (HTST) processing, we can expect substantial further growth, reflecting quality and convenience advantages over products processed from yesterday's technologies. The anticipated growth in particulates is driven by both materials and packaging advances and only requires modest marketing of the organoleptic advantages to establish their place on menu options. The directions taken in packaging developments, especially those interfacing with the latest and established methods of processing, are increasingly influ• enced by the need to design packaging on a cradle-to-grave basis. Time was when multi-laminated films on board satisfied the total needs of consumers of aseptic products. The problems of recycling combustible, i.e. energy generating mate• rials laminated with aluminium foil, are becoming sensitive issues in a world preoccupied with recycling, and are creating openings for alternative and envi• ronmentally friendly material combinations. This book brings together advanced technologies in the field, to provide information for professionals with interests in aseptic processing on how to go about selecting a system appropriate to their commercial needs and constraints. It covers markets for products, processing and materials in the USA, Europe and Japan. It avoids or minimizes duplication with works in similar fields and emphasizes the technologies behind processing plant, especially those for han• dling particulates. Integration of processing with packaging is discussed, includ• ing the latest proven technologies based on microwave cooking, resistive heating and neutral aseptic handling of packaging. The book also includes an apprecia• tion of packaging requirements, microbiological aspects applied to aseptic pro• cessing, and critical control point hazard analysis (HACCP). The efficacy of HTST is highlighted in terms of heightened sensory quality and improved sterility. The Dole process is included because it has stood the test of time and was an early adjunct to HTST. It is capable of being developed for particulates and, perhaps as importantly, with the emphasis on recycling tin-plate or its equivalent, is readily recyclable without unduly disturbing the environment. This book is recommended reading for food and packaging technologists, production and process engineers, quality control management, material conver- vi ASEPTIC PROCESSING AND PACKAGING OF PARTICULATE FOODS tors, microbiologists and, last but not least, market research and marketing personnel of food manufacturing companies and trading operations. Finally, I should like to thank each one of the authors for the time, patience and commitment that they put into presenting their contributions, and especially Margaret for her unstinting support throughout.

E.M.A. W. Contents

1 Aseptic processing and packaging of food particulates 1 N.BUCHNER

1.1 Introduction and basic principles 1 1.1.1 Advantages over in-container sterilized foods 1 1.1.2 Advantages over pasteurized chilled foods 2 1.1.3 Advantages over 'c!eanfill' 2 1.1.4 Advantages over frozen products 3 1.1.5 Advantages over dried products 3 1.2 Developments in aseptic processing and filling 3 1.3 Aseptic processing-methodology 4 1.3.1 Sterilization of products 4 1.3.2 Sterilization of packaging materials and packages 9 1.4 Maintaining sterility in aseptic machines 10 1.4.1 Sterilization of aseptic installations 11 1.5 Filling 12 1.5.1 Filling principles forliquids 12 1.5.2 Filling principles for particulate mixtures 13 1.6 Closing packs 14 1.6.1 Heat-sealing 14 1.6.2 Types of packs 15 1.7 Typical machines for aseptic packaging of particulate foods 16 1.7.1 F onnlfill!seal machine for pouches 16 1.7.2 Thermofonnlfill!seal machine for cups and trays 17 1.7.3 Filling and closing line for bottles and jars 18 1.7.4 Fonnlfill!seal machine for cartons from sleeves 19 I. 7.5 Fonnlfill!seal machine for cartons from the reel 20 1.8 Conclusion 21 References 21

2 The market for aseptic products, processing and packaging systems 23 E. M. A. WILLHOFT 2.1 Introduction 23 2.2 The west European market 27 2.3 The US market 30 2.3.1 Alfa Laval 30 2.3.2 APV Crepaco 31 2.3.3 ASTEC 32 2.3.4 Cherry Burrell 33 2.3.5 DASI (TCI-Superior) 34 2.3.6 FranRica 34 2.3.7 Terlet 35 2.4 Packaging systems 35 2.5 Future requirements and trends 37 References 38

3 Packaging materials-their properties and criteria for selection 39 B.1. TURTLE 3.1 Introduction' 39 3.2 Pack selection 40 Vlll ASEPTIC PROCESSING AND PACKAGING OF PARTICULATE FOODS

3.3 Pack criteria 40 3.3.1 Product containment 41 3.3.2 Physical protection 41 3.3.3 Food safety 41 3.3.4 Shelf-life 41 3.3.5 Communication of information 41 3.3.6 Sales appeal 42 3.3.7 Cost-effectiveness 42 3.4 Packaging materials compared 42 3.4.1 Metal containers 43 3.4.2 Rigid plastics containers 47 3.4.3 High-barrier plastics containers 55 3.4.4 The special needs of plastics aseptic packaging 57 3.4.5 Glass containers 59 3.4.6 Flexible packaging materials 61 3.5 Heat-sealing 64 3.5.1 Testing for leaking packs 66 3.6 Shelf-life 66 3.7 Aseptic packs 67 3.8 The cost of packaging 68 3.8.1 Cost-effective packaging 68 3.9 Food packaging legislation 69 3.9.1 EC legislation 69 3.1 0 Packaging and the environment 70 3.10.1 Litter 70 3.10.2 Disposal of waste 71 3.10.3 Use of natural resources 71 3.10.4 Recycling 72

4 Ohmic heating 74 P. 1. SKUDDER 4.1 Introduction 74 4.1.1 Consumer products 74 4.1.2 Aseptic processing 74 4.1.3 Ohmic heating 74 4.2 Principles of aseptic processing 75 4.2.1 Thermal sterilisation-the options 75 4.2.2 Principles of thermal sterilisation 75 4.3 Processing options 76 4.3.1 Indirect plate heat exchangers 76 4.3.2 Indirect tubular heat exchangers 76 4.3.3 Direct steam injection and steam infusion 76 4.3.4 Scraped surface heat exchangers 77 4.4 Ohmic heating 77 4.2.1 Principles of ohmic heating 77 4.2.2 Advantages of ohmic heating 78 4.5 Design of the ohmic heater 78 4.5.1 Mechanical design 78 4.5.2 Temperature control 78 4.6 Aseptic processing using the ohmic heater 79 4.6.1 Processing system 79 4.6.2 Plant sterilisation 80 4.6.3 Product processing 80 4.6.4 Alternative cooling 81 4.6.5 Cleaning 81 4.6.6 Throughputs 82 4.7 Product quality 82 CONTENTS ix

4.7.1 Microbial process validation 82 4.7.2 Cooking value 84 4.8 Products 87 4.9 Commercial installations 87 4.9.1 Research systems 87 4.1 0 Conclusions 89 Acknowledgements 89 Reference 89

5 The ERCA neutral aseptic system 90 C. J. ROBINSON 5.1 Introduction 90 5.1.1 Sterility without chemicals 90 5.2 Basic construction of the ERCA machine 92 5.2.1 Preparation of materials 92 5.2.2 Machine operation 93 5.3 Extension of basic machine to NAS® specification 97 5.4 NAS® materials 97 5.4.1 Plastic base web 98 5.4.2 Lidding film 99 5.4.3 Verification of sterility ofNAS® co-extruded materials 99 5.5 NAS® machines 100 5.5.1 General description 100 5.5.2 Plastic film introduction 100 5.5.3 Lidding film introduction 103 5.5.4 Sterile tunnel 104 5.5.5 Forming 105 5.5.6 Filler 106 5.6 Product preparation 108 5.6.1 Production of superheated water 109 5.6.2 Blending 109 5.6.3 UHT process 109 5.6.4 Cooling 110 5.6.5 Cleaning (CIP) 110 5.6.6 Process control 110 5.7 Future developments 110

6 Microwave processing and package integration 112 R. E. COLES 6.1 The technology revolution 112 6.2 Consumer influence 113 6.3 Packaging needs 114 6.4 Packaging materials for microwaveable foods 115 6.4.1 Microwave-passive materials 115 6.4.2 Microwave-active and microwave-reflective materials 118 6.4.3 Package geometry for even heating 120 6.5 Microwave heating principles 124 6.5.1 The significance of the wave 125 6.5.2 Microwave interactions with materials 125 6.5.3 Microwave heating factors 126 6.6 Extending product shelf-life 131 6.6.1 HTST processing 131 6.6.2 Microbial and sensory decay 134 6.6.3 Pasteurization versus sterilization 135 6.6.4 Temperature measurement 137 6.6.5 Microwave sterilization 138 x ASEPTIC PROCESSING AND PACKAGING OF PARTICULATE FOODS

6.7 Types of microwave processing systems 140 6.7.1 The frequency debate 140 6.7.2 Penetration depths 142 6.7.3 Operating efficiencies 143 6.7.4 Relative operating costs for industrial microwave processing 143 6.7.5 Batch versus continuous equipment 143 6.7.6 Continuous microwave pressure vessels 143 6.7.7 Thermal stabilisation 145 Acknowledgements 146 References 146

7 The Dole process 148 F. S. WHITE 7.1 Introduction 148 7.2 Technology overview 148 7.3 The Dole system 148 7.3.1 Can-sterilizing unit 149 7.3.2 The filling section 149 7.3.3 Instrumentation and controls 150 7.3.4 System operations 151 7.3.5 Superheated steam 153

8 Microbiological aspects of aseptic processing and packaging 155 D. A. JOYCE 8.1 Introduction 155 8.2 Foodbome microorganisms 156 8.2.1 Food poisoning 157 8.3 Raw materials 159 8.4 Processing 160 8.5 Aseptic packaging 162 8.5.1 Hydrogen peroxide and peracids 162 8.5.2 Ultraviolet irradiation 163 8.5.3 Ionising irradiation 164 8.5.4 Thermal treatment 164 8.5.5 Integrity of packs 165 8.6 Validation of aseptic processing and packaging 165 8.6.1 Plant commissioning 166 8.6.2 Sterility testing 167 8.7 Quality control 169 8.7.1 End-product analysis 169 8.7.2 The role of microbiological analysis 171 8.8 Quality management 175 8.8.1 Hazard analysis: critical control point systems 176 8.9 Further thoughts 178 References 179

9 Aseptic packaging of liquid foods 181 S. WAKABAYASHI 9.1 Introduction 181 9.2 Requirements for an aseptic packaging machine 181 9.3 Performance and features of an aseptic packaging machine 183 9.3.1 Sterilization of packaging materials 183 9.3.2 Filling and sealing 185 9.3.3 Aseptic positive-pressure chamber 186

Index 189 Contributors

Professor Dr N. Buchner University of Stuttgart-Hohenheim, Postfach 70 0562, Schloss 1, 7000 Stuttgart 70 (Hohenheim), Germany Mr R. E. Coles Foodpack Information Centre, 16 Kenilworth Road, Cubbington, Leamington Spa, Warwick, UK Mr D. A. Joyce David A. Joyce Associates, Manley Common, Cheshire W A6 9ES, UK Mr C. J. Robinson Remy Gimpel Ltd, 103-109 Lavender Hill, London SWl15QI, UK Dr P. J. Skudder APV Baker Ltd, Automated Processes Division, PO Box 4, Gatwick Road, Crawley, Sussex RH4 2QB, UK Mr B. I. Turtle 45 Priory Orchard, Wantage, OX12 9EL, UK Mr S. Wakabayashi Shikoku Kakoki Co Ltd, Toyo Bldg, No 20, 12- banchi, Jingu-mae 6-chome, Shibuya-ku, Tokyo 150, Japan Dr E. M. Willhoft Epsom Technical Group Services, 41 Higher Green, Epsom, Surrey KT17 3BB, UK Mr F. S. White Graham Engineering Corp, 1420 Sixth Avenue, PO Box 1140, York, Pennsylvania 17405, USA