FOOD PACKAGING TECHNOLOGY Edited by RICHARD COLES Consultant in Food Packaging, London DEREK M C DOWELL Head of Supply and Packaging Division Loughry College, Northern Ireland and MARK J. KIRWAN Consultant in Packaging Technology London Blackwell Publishing © 2003 by Blackwell Publishing Ltd Editorial Offices: 9600 Garsington Road, Oxford OX4 2DQ Tel: +44 (0) 1865 776868 108 Cowley Road, Oxford OX4 1JF, UK Tel: +44 (0) 1865 791100 Blackwell Munksgaard, 1 Rosenørns Allè, P.O. Box 227, DK-1502 Copenhagen V, Denmark Tel: +45 77 33 33 33 Blackwell Publishing Asia Pty Ltd, 550 Swanston Street, Carlton South, Victoria 3053, Australia Tel: +61 (0)3 9347 0300 Blackwell Publishing, 10 rue Casimir Delavigne, 75006 Paris, France Tel: +33 1 53 10 33 10 Published in the USA and Canada (only) by CRC Press LLC 2000 Corporate Blvd., N.W. 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First published 2003 Library of Congress Cataloging in Publication Data A catalog record for this title is available from the Library of Congress British Library Cataloguing in Publication Data A catalogue record for this title is available from the British Library ISBN 1–84127–221–3 Originated as Sheffield Academic Press Set in 10.5/12pt Times by Integra Software Services Pvt Ltd, Pondicherry, India Printed and bound in Great Britain, using acid-free paper by MPG Books Ltd, Bodmin, Cornwall For further information on Blackwell Publishing, visit our website: www.blackwellpublishing.com Contributors Helen Brown Biochemistry Section Manager, Campden & Chorley- wood Food Research Association, Chipping Campden, Gloucestershire, GL55 6LD, UK Richard Coles Consultant in Food Packaging, Packaging Consultancy and Training, 20 Albert Reed Gardens, Tovil, Maid- stone, Kent ME15 6JY, UK Brian P.F. Day Research Section Leader, Food Packaging & Coatings, Food Science Australia, 671 Sneydes Road (Private Bag 16), Werribee, Victoria 3030, Australia Mike Edwards Microscopy Section Manager, Chemistry & Biochem- istry Department, Campden & Chorleywood Food Research Association, Chipping Campden, Glouces- tershire, GL55 6LD, UK Patrick J. Girling Consultant in Glass Packaging, Doncaster, UK (for- merly with Rockware Glass) Bruce Harte Director, Michigan State University, School of Pack- aging, East Lansing, Michigan, 48824-1223, USA Mark J. Kirwan Consultant in Packaging Technology, London, UK (formerly with Iggesund Paperboard) Nick May Senior Research Officer, Process and Product Devel- opment Department, Campden & Chorleywood Food Research Association, Chipping Campden, Glouces- tershire, GL55 6LD, UK Derek McDowell Head of Supply and Packaging Division, Loughry College, The Food Centre, Cookstown, Co. Tyrone, BT80 9AA, Northern Ireland Michael Mullan Head of Food Education and Training Division, Loughry College, The Food Centre, Cookstown, Co. Tyrone, BT80 9AA and Department of Food Science, The Queen’s University of Belfast, Newforge Lane, Belfast, BT9 5PX, Northern Ireland xvi CONTRIBUTORS Bev Page Packaging Consultant, Oak Shade, 121 Nottingham Road, Ravenshead, Nottingham NG15 9HJ, UK John W. Strawbridge Consultant in Plastics Packaging, Welwyn, UK (for- merly with Exxon-Mobil) Gary S. Tucker Process Development Section Leader, Department of Process and Product Development, Campden & Chorleywood Food Research, Association Chipping Campden, Gloucestershire, GL55 6LD, UK Diana Twede Associate Professor, Michigan State University, School of Packaging, East Lansing, Michigan, 48824-1223, USA James Williams Flavour Research and Taint Investigations Manager, Campden & Chorleywood Food Research Associ- ation, Chipping Campden, Gloucestershire, GL55 6LD, UK Preface This volume informs the reader about food preservation processes and techniques, product quality and shelf life, and the logistical packaging, packaging materials, machinery and processes, necessary for a wide range of packaging presentations. It is essential that those involved in food packaging innovation have a thor- ough technical understanding of the requirements of a product for protection and preservation, together with a broad appreciation of the multi-dimensional role of packaging. Business objectives may be: • the launch of new products or the re-launch of existing products • the provision of added value to existing products or services • cost reduction in the supply chain. This book sets out to assist in the attainment of these objectives by informing designers, technologists and others in the packaging chain about key food packaging technologies and processes. To achieve this, the following five principal subject areas are covered: 1. food packaging strategy, design and development (chapter 1) 2. food bio-deterioration and methods of preservation (chapter 2) 3. packaged product quality and shelf life (chapter 3) 4. logistical packaging for food marketing systems (chapter 4) 5. packaging materials and processes (chapters 5–10). Chapter 1 introduces the subject of food packaging and its design and develop- ment. Food packaging is an important source of competitive advantage for retailers and product manufacturers. Chapter 2 discusses bio-deterioration and methods of food preservation that are fundamental to conserving the integrity of a product and protecting the health of the consumer. Chapter 3 discussess packaged product quality and shelf life issues that are the main concerns for product stability and consumer acceptability. Chapter 4 discusses logistical packaging for food marketing systems – it considers supply chain efficiency, distribution hazards, opportunities for cost reduction and added value, com- munication, pack protection and performance evaluation. Chapters 5, 6, 7 and 8 consider metal cans, glass, plastics and paper and paperboard, respectively. Chapters 9 and 10 discuss active packaging and modified atmosphere packaging (MAP) respectively – these techniques are used to extend the shelf life and/or guarantee quality attributes such as nutritional content, taste and the colour of many types of fresh, processed and prepared foods. xviii PREFACE The editors are grateful for the support of authors who are close to the latest developments in their technologies, and for their efforts in making this know- ledge available. We also wish to extend a word of gratitude to others who have contributed to this endeavour: Andy Hartley, Marketing Manager, and Sharon Crayton, Prod- uct Manager of Rockware Glass, UK; Nick Starke, formerly Head of Research & Development, Nampak, South Africa; Frank Paine, Adjunct Professor, School of Packaging, Michigan State University; and Susan Campbell. Richard Coles Derek McDowell Mark Kirwan Contents Contributors xv Preface xvii 1 Introduction 1 RICHARD COLES 1.1 Introduction 1 1.2 Packaging developments – an historical perspective 2 1.3 Food supply and the protective role of packaging 4 1.4 The value of packaging to society 7 1.5 Definitions and basic functions of packaging 8 1.6 Packaging strategy 9 1.7 Packaging design and development 9 1.7.1 The packaging design and development framework 12 1.7.1.1 Product needs 13 1.7.1.2 Distribution needs and wants of packaging 13 1.7.1.3 Packaging materials, machinery and production processes 16 1.7.1.4 Consumer needs and wants of packaging 18 1.7.1.5 Multiple food retail market needs and wants 22 1.7.1.6 Environmental performance of packaging 26 1.7.2 Packaging specifications and standards 28 1.8 Conclusion 29 Literature reviewed and sources of information 29 2 Food biodeterioration and methods of preservation 32 GARY S. TUCKER 2.1 Introduction 32 2.2 Agents of food biodeterioration 33 2.2.1 Enzymes 33 2.2.2 Microorganisms 34 2.2.2.1 Bacteria 35 2.2.2.2 Fungi 38 2.2.3 Non-enzymic biodeterioration 40 2.3 Food preservation methods 41 2.3.1 High temperature 41 2.3.1.1 Blanching 42 2.3.1.2 Thermal processing 42 2.3.1.3 Continuous thermal processing (aseptic) 47 2.3.1.4 Pasteurisation 51 2.3.2 Low temperature 52 2.3.2.1 Freezing 52 2.3.2.2 Chilling and cooling 53 vi CONTENTS 2.3.3 Drying and water activity control 54 2.3.4 Chemical preservation 56 2.3.4.1 Curing 57 2.3.4.2 Pickling 58 2.3.4.3 Smoking 58 2.3.5 Fermentation 59 2.3.6 Modifying the atmosphere 60 2.3.7 Other techniques and developments 61 2.3.7.1 High pressure processing 61 2.3.7.2 Ohmic heating 62 2.3.7.3 Irradiation 62 2.3.7.4 Membrane processing 62 2.3.7.5 Microwave processing 63 References 63 3 Packaged product quality and shelf life 65 HELEN BROWN and JAMES WILLIAMS 3.1 Introduction 65 3.2 Factors affecting product quality and shelf life 68 3.3 Chemical/biochemical processes 69 3.3.1 Oxidation 70 3.3.2 Enzyme activity 73 3.4 Microbiological processes 74 3.4.1 Examples where packaging is key to maintaining microbiological shelf life 75 3.5 Physical and physico-chemical processes 77 3.5.1 Physical damage 77 3.5.2 Insect damage 78 3.5.3 Moisture changes 78 3.5.4 Barrier to odour pick-up 81 3.5.5 Flavour scalping 81 3.6 Migration from packaging to foods 81 3.6.1 Migration from plastic packaging 83 3.6.2 Migration from other packaging materials 86 3.6.3 Factors affecting migration from food contact materials 88 3.6.4 Packaging selection to avoid migration and packaging taints 89 3.6.5 Methods for monitoring migration 89 3.7 Conclusion 91 References 91 4 Logistical packaging for food marketing systems 95 DIANA TWEDE and BRUCE HARTE 4.1 Introduction 95 4.2 Functions of logistical packaging 96 4.2.1 Protection 97 4.2.2 Utility/productivity 98 4.2.3 Communication 99 CONTENTS vii 4.3 Logistics activity-specific and integration issues 100 4.3.1 Packaging issues in food processing and retailing 100 4.3.2 Transport issues 101 4.3.3 Warehousing issues 104 4.3.4 Retail customer service issues 106 4.3.5 Waste issues 107 4.3.6 Supply chain integration issues 108 4.4 Distribution performance testing 109 4.4.1 Shock and vibration testing 110 4.4.2 Compression testing 111 4.5 Packaging materials and systems 112 4.5.1 Corrugated fiberboard boxes 112 4.5.2 Shrink bundles 115 4.5.3 Reusable totes 115 4.5.4 Unitization 116 4.6 Conclusion 119 References 119 5 Metal cans 120 BEV PAGE, MIKE EDWARDS and NICK MAY 5.1 Overview of market for metal cans 120 5.2 Container performance requirements 120 5.3 Container designs 121 5.4 Raw materials for can-making 123 5.4.1 Steel 123 5.4.2 Aluminium 124 5.4.3 Recycling of packaging metal 124 5.5 Can-making processes 124 5.5.1 Three-piece welded cans 125 5.5.2 Two-piece single drawn and multiple drawn (DRD) cans 126 5.5.3 Two-piece drawn and wall ironed (DWI) cans 127 5.6 End-making processes 129 5.6.1 Plain food can ends and shells for food/drink easy-open ends 130 5.6.2 Conversion of end shells into easy-open ends 130 5.7 Coatings, film laminates and inks 131 5.8 Processing of food and drinks in metal packages 132 5.8.1 Can reception at the packer 132 5.8.2 Filling and exhausting 133 5.8.3 Seaming 135 5.8.4 Heat processing 137 5.8.5 Post-process can cooling, drying and labelling 138 5.8.6 Container handling 139 5.8.7 Storage and distribution 140 5.9 Shelf life of canned foods 141 5.9.1 Interactions between the can and its contents 142 5.9.2 The role of tin 142 5.9.3 The dissolution of tin from the can surface 144 5.9.4 Tin toxicity 145 viii CONTENTS 5.9.5 Iron 146 5.9.6 Lead 147 5.9.7 Aluminium 147 5.9.8 Lacquers 147 5.10 Internal corrosion 148 5.11 Stress corrosion cracking 148 5.12 Environmental stress cracking corrosion of aluminium alloy beverage can ends 149 5.13 Sulphur staining 149 5.14 External corrosion 149 5.15 Conclusion 150 References and further reading 151 6 Packaging of food in glass containers 152 P.J. GIRLING 6.1 Introduction 152 6.1.1 Definition of glass 152 6.1.2 Brief history 152 6.1.3 Glass packaging 152 6.1.4 Glass containers market sectors for foods and drinks 153 6.1.5 Glass composition 153 6.1.5.1 White flint (clear glass) 153 6.1.5.2 Pale green (half white) 154 6.1.5.3 Dark green 154 6.1.5.4 Amber (brown in various colour densities) 154 6.1.5.5 Blue 154 6.2 Attributes of food packaged in glass containers 154 6.2.1 Glass pack integrity and product compatibility 156 6.2.1.1 Safety 156 6.2.1.2 Product compatibility 156 6.2.2 Consumer acceptability 156 6.3 Glass and glass container manufacture 156 6.3.1 Melting 156 6.3.2 Container forming 157 6.3.3 Design parameters 158 6.3.4 Surface treatments 158 6.3.4.1 Hot end treatment 158 6.3.4.2 Cold end treatment 159 6.3.4.3 Low-cost production tooling 160 6.3.4.4 Container inspection and quality 161 6.4 Closure selection 163 6.4.1 Normal seals 164 6.4.2 Vacuum seals 164 6.4.3 Pressure seals 164 6.5 Thermal processing of glass packaged foods 165 6.6 Plastic sleeving and decorating possibilities 165 6.7 Strength in theory and practice 166 6.8 Glass pack design and specification 167 6.8.1 Concept and bottle design 167 6.9 Packing – due diligence in the use of glass containers 169 [...]... References Further reading 7 Plastics in food packaging MARK J KIRWAN and JOHN W STRAWBRIDGE 7.1 7.2 7.3 7.4 Introduction 7.1.1 Definition and background 7.1.2 Use of plastics in food packaging 7.1.3 Types of plastics used in food packaging Manufacture of plastics packaging 7.2.1 Introduction to the manufacture of plastics packaging 7.2.2 Plastic film and sheet for packaging 7.2.3 Pack types based on use... provides a context for considering the many types of packaging technology available It includes an historical perspective of some packaging developments over the past 200 years and outlines the value of food packaging to society It highlights the protective and logistical roles of packaging and introduces packaging strategy, design and development Packaging technology can be of strategic importance to a... storage 8 FOOD PACKAGING TECHNOLOGY The food industry is aware of current public concerns related to packaging which include: • • • • • • • • • 1.5 packaging litter and the volume of packaging waste in municipal waste cost of disposal and recovery of discarded packaging in municipal waste pollution associated with methods of disposal, i.e landfill and incineration ease of opening perception of over -packaging. .. roles of packaging are to contain, protect/preserve food and inform the user Thereby, food waste may be minimised and the health of the consumer safeguarded 6 FOOD PACKAGING TECHNOLOGY Packer co-ops Farms Primary processors Secondary processors Regional distribution centres, wholesalers, cash and carry Retail outlets Consumer Figure 1.1 Food distribution systems (adapted from Paine & Paine, 1983) Packaging. .. costs 1.4 The value of packaging to society The value of food packaging to society has never been greater nor, paradoxically, has packaging attracted so much adverse media publicity and political attention In response, stakeholders in the food industries need to fully appreciate and actively promote the positive contributions that their packaging makes to the quality of life Food packaging is governed... packaging design and development to take account of technological, marketing, legal, logistical and environmental requirements that are continually changing Consequently, it is asserted that those involved in packaging need to develop an 2 FOOD PACKAGING TECHNOLOGY integrated view of the effect on packaging of a wide range of influences, including quality, production, engineering, marketing, food technology. .. in food science and technology, packaging materials and machine technology An overview of some developments in packaging during the past 200 years is given below • 1800–1850s In 1809 in France, Nicolas Appert produced the means of thermally preserving food in hermetically sealed glass jars In 1810, Peter Durand designed the soldered tinplate canister and commercialised the use of heat preserved food. .. and its operational/financial impacts, for example, regulations regarding food hygiene, labelling, weights and measures, food contact materials, due diligence etc Environmental requirements or pressures and their impacts, for example, light-weighting to reduce impact of taxes or levies on amount of packaging used 10 FOOD PACKAGING TECHNOLOGY innovation is ahead of its time but may be later adopted when... design etc Define quality standards and packaging specifications Conduct production and machine trials: efficiency and productivity performance Plan line change-overs Develop inspection methods and introduce a quality assurance service Commission production line for new or changed packaging systems Fine-tune packaging operations and specifications 12 FOOD PACKAGING TECHNOLOGY Table 1.3 Typical handling... sufficient market demand for an innovation to succeed 1.3 Food supply and the protective role of packaging Packaging for consumer products is an area where supply and demand is continuously changing due to the development of an international food market and adaptation to consumer, distribution, legal and technological requirements Broad external influences on packaging for fast-moving consumer products may be . FOOD PACKAGING TECHNOLOGY Edited by RICHARD COLES Consultant in Food Packaging, London DEREK M C DOWELL Head of Supply and Packaging Division Loughry College,. from packaging to foods 81 3.6.1 Migration from plastic packaging 83 3.6.2 Migration from other packaging materials 86 3.6.3 Factors affecting migration from food contact materials 88 3.6.4 Packaging. in packaging need to develop an 2 FOOD PACKAGING TECHNOLOGY integrated view of the effect on packaging of a wide range of influences, including quality, production, engineering, marketing, food