A Handbook of Food Packaging

A HANDBOOK OF FOOD PACKAGING

Second edition

Frank A. Paine B.Sc., C.Chem., F.R.S.C., F.I.F.S.T., F.Inst.Pkg., F.Inst.D.

Secretary General International Association of Packaging Research Institutes

and Adjunct Professor

School of Packaging Michigan State University

and

Heather Y. Paine B.Sc., M.Sc., F.I.F.S.T., M.I.P.R.

Consultant Food Scientist

Published under the authority of The Institute of Packaging

SPRINGER-SCIENCE+BUSINESS MEDIA, BV

First edition 1983

Second edition 1992

© 1983, 1992 Springer Science+Business Media Dordrecht Originally published by Chapman & Hali in 1983, 1992 Softcover reprint ofthe hardcover 2nd edition 1983, 1992

Typeset in 10/ 12 pt Times New Roman by Thomson Press (India) Ltd, New Delhi

ISBN 978-1-4613-6214-2 ISBN 978-1-4615-2810-4 (eBook) DOI 10.1007/978-1-4615-2810-4 Apan from any fair dealing for the purposes OI researcn or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the Iicences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms of licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the publishers at the Glasgow address printed on this page.

The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or Iiability for any errors or omissions that may be made.

A catalogue record for this book is available from the British Library

Library of Congress Cataloguing-in-Publication data available

Preface

This is the second edition of a successful title first published in 1983 and now therefore a decade out of date. The authors consider the development of the right package for a particular food in a particular market, from the point of view of the food technologist, the packaging engineer and those concerned with marketing. While the original format has been retained, the contents have been thoroughly revised to take account of the considerable advances made in recent years in the techniques offood processing, packaging and distribution.

While efficient packaging is even more a necessity for every kind of food, whether fresh or processed, and is an essential link between the food producer and the consumer, the emphasis on its several functions has changed. Its basic function is to identify the product and ensure that it travels safely through the distribution system to the consumer. Packaging designed and constructed solely for this purpose adds little or nothing to the value of the product, merely preserving farm or processor freshness or preventing physical damage, and cost effectiveness is the sole criterion for success. If, however, the packaging facilitates the use of the product, is reusable or has an after-use, some extra value can be added to justify the extra cost and promote sales.

Many examples of packaging providing such extra value can be cited over the last decade. For example, those concerned with food production have produced new methods of processing and preservation which have had a great influence on filling and packaging methods. HTST pasteurisation, aseptic processing and reduced amounts of additives all place greater emphasis on getting the packaging right. Retailers are now required by consumers to meet the desire for a 'fresh' concept in food, and the better control of freezers and chill cabinets now demanded places more stress on the packaging process, particularly where 'sous vide' and modified atmosphere packaging are concerned. However, while every consumer wants a quality product delivered in a package adequate to maintain that quality for the necessary shelf-life, in almost every instance it is the product alone that the customer wants: the packaging, with a few exceptions, is an ancillary part of the transaction. Indeed, if the packaging appears to be over-elaborate, it may well create the impression that the cost of the product has been unnecessarily raised by the packaging, which will have a negative effect on sales. All packages must be easy and safe to handle, simple to open and use, and provide few problems in their disposal.

VI PREFACE

These considerations will influence factors such as the weight, size, shape, structure and the incorporation of convenience into the structure of the primary packaging and that used for transport and storage. The provision of convenience, whether of the primary packaging or the shipping container, is much wider now than in the early 1980s. Easy opening must now be tempered by seal integrity and the more recent risks of pilfering and malicious tampering.

Finally a far more sophisticated public must be given a cleaner, more modern approach to the graphics and promotional needs of the packaging than its 1980s counterpart.

This second edition, as its predecessor, is written for food technologists wishing to understand more fully those aspects of packaging technology that are relevant to the preservation, distribution and marketing of a particular food; packaging engineers wishing to know more about those aspects of science and technology that will influence the packaging process; and for students of food science and technology requiring an integrated approach to the subject.

Thanks are due to all those who in one way or another by argument, discussion and advice have contributed to the knowledge and understanding of the authors.

F.A.P. H.Y.P.

Contents

1 Introduction to packaging 1 History I Definitions 3 The need for packaging 5 Designing successful packaging 8

Product assessment 8 The hazards of distribution 8 Good package design and supermarket selling 10 Marketing requirements 14 Packaging and the self-service store 14 The package and advertising 16 The package and the price of the product 16

Packaging materials selection and machinery considerations 17 Cost 17

The place of packaging within the marketing complex 19 Materials utilization 20 Machinery and line efficiency 22 Movement in distribution 22 Management 23

Properties and forms of packaging materials 23 Food process classification 26 References 32

2 Graphics and package design 33 Introduction 33 Management's role 33 Packaging and modern merchandising 34 Meeting customer and consumer needs 36 Beware the half truth and consider the alternative 37 Trends 39 Summary of consumer needs 39 The function of packaging graphics 40 The main printing processes 40

Letterpress 40 Flexography 44 Lithography 45 Gravure 47 Silk screen 48 Ink-jet printing 49 Hot die stamping and gold blocking 50

Factors affecting the choice of a printing process 50 References 52

3 Notes on packaging materials 53 Paper-based packing 53

What is wood? 53 Pulping 53

Vlll

Beating Paper testing Types of paperboard

Plastics Thermosets Thermoplastics Polyesters

CONTENTS

Flexible packaging materials based on films and foils Materials tests on flexible packaging

Glass containers Properties of glass containers Sealing of glass containers

Metal packaging: the basic materials Cans and tin boxes Closures

Natural materials Round-stick joinery Straw Waxes and bitumen Stoneware Textiles Wicker baskets

References

4 Packaging machinery Production and packaging line requirements The property profile Bottling

Bottle feeding Bottle cleaning Filling liquids Filling dry goods (powders and granular material) Statistical recording-the legal requirements Capping of bottles and jars Labelling bottles and jars Case packing and sealing Shrink- or stretch-wrapping Palletizing

Canning operations Handling and storage of empty cans Cleaning empty cans Product preparation Filling Closing (seaming) Processing Cooling Handling and storage of filled cans

Wrapping operations Bags: manufacture, filling and closing Paper bags Film bags Open mesh bags Bag filling and closing equipment Bag-in-box packages

Cartoning Cartons for liquid products Cartons for solid products Cartoning systems

54 55 57 59 61 61 68 68 70 78 78 82 83 85 92 94 94 94 95 95 95 96 96

97 97 99

100 103 103 104 106 110 114 116 116 117 117 118 118 118 119 119 120 121 124 125 126 130 131 131 132 132 133 133 134 135 139

CONTENTS ix

Form, fill and seal machines 141 Vertical form-fill-seal (fJ.s.) machines 142 Packaging machinery for vertical fJ.s. pillow packs 146 Horizontal fJ.s. machines 148 Packaging machinery for horizontal fJ.s. sachet packs 153 Thermoformed fJ.s. packs 153

Labelling 159 Purchasing, installation and operation of labelling machinery 162 Container handling 162

Standard case sealing, wrap-around case sealing and tray erection 162 Standard case sealing 162 Adhesive application systems 162 Wrap-around case sealing 163 Tray erection 164

Organization of packing lines 165 Further reading 166

5 Packaging for physical distribution 167 Introduction 167

Functions of a shipping container 168 Primary, secondary and tertiary levels of packaging 169

Fibreboard case performance 170 Board properties affecting stacking performance 175

Unitizing methods 181 Film wraps 182 Pallet stabilizing adhesives 184 Strapping materials and methods 184

References 186

6 Spoilage and deterioration indices 187 Biodeterioration 187

Effects of temperature on senescence 187 Microbial growth 188 Food spoilage and food poisoning 192 Moulds and yeasts 193 Preventing bacterial and mould growth 193 Insect infestation 194 Rodents and birds 194

Abiotic spoilage 195 The role of water in foods 195 Sorption isotherms 196

References 203

7 Fresh and chilled foods: meat, poultry, fish, dairy products and eggs 205 Meat 205

Preparation of meat 205 Chilling and chilled storage 206 Cutting and boning 206 Deterioration of fresh and chilled meat 206 Chilled transport to the retail outlet 209 Wholesale packaging 209 Retailing 210 Vacuum packaging of meat 212 Modified atmosphere packaging 214

Poultry 216 Preparation and spoilage 216

X CONTENTS

Packaging 216 Modified atmosphere packaging of poultry 217

Fish and shellfish 217 Factory ships 217 Fish processors 217 Handling and transport 218 Chilling 218 Fish farming 219 Retailing 219 Deterioration of fresh and chilled fish 219 Prepackaging 221 Modified atmosphere packaging of fresh fish 221 Vacuum packaging of fresh fish 221

Milk 222 Quality and composition 222 Effect of temperature on bacterial growth 223 Pasteurization 223 Characteristic spoilage of pasteurized milk 224 Packaging 224 Returnable bottles 225

Other dairy products 226 Butter 226 Protection required 227

Dairy spreads 227 Eggs 227

Packaging requirements 227 Cream 228 Guidelines for packers, manufacturers, distributers and consumers 228 References 229

8 Fresh fruits and vegetables (including herbs, spices and nuts) 231 Fruits and vegetables 231

Variability 231 The growing process, respiration and ripening 231 Temperature 235 Composition of the atmosphere 237 Bacteriological conditions 241 Handling 241 Transport 241 Packaging 241 Pre packed fruit and vegetables 242 Modified atmosphere packaging 242 Prepared vegetables and salads 245

Fresh herbs and spices 245 Nuts and seeds 246 References 246

9 Frozen foods 248 Freezing 248

Commercial freezing methods 249 Storage and distribution 249 Protection needed by frozen foods 250 Types of package 251

Frozen meat and poultry 252 Freezer burn 253 The freezing process 253 Commercial freezing methods 254 Frozen poultry 254

Frozen fish Effect of freezing on fish Methods of freezing Storage Packaging frozen fish Frozen fish products

Frozen fruits and vegetables Other frozen products

Ice-cream Cook-freeze products

CONTENTS

Guidelines for packers, distributors, retailers and consumers Future trends References

10 Heat-processed foods (including irradiated foods, etc.) Heat processing

Commercial sterilization Factors affecting resistance of microorganisms to high temperatures Factors affecting the rate of heat penetration Pasteurization Blanching General spoilage problems with canned foods

High-barrier plastics packaging Stepcan Letpak

Aseptic processing Aseptic canning Aseptic packaging using flexible materials Aseptic processing of milk and dairy products Aseptic processing of fruit and vegetable juices Problems with particulates

So us vide Packaging for microwavable foods

Packaging materials Microwave active materials (susceptors and receptors)

Irradiation Methods of irradiation Applications Detection methods

Ultraviolet light Ultrasonics High pressure techniques References

11 Dried and moisture sensitive foods Reduction of available water

Methods of drying Moisture levels of dried and moisture sensitive foods General spoilage considerations of dehydrated foods Oxygen scavengers

Active packaging systems Packaging requirements for different moisture levels

References

12 Other processed foods Preservation by chemical means

Classes of chemical preservative

Xl

255 255 256 256 256 257 257 258 259 260 261 261 263

265 265 265 265 266 268 269 269 274 275 275 276 278 278 280 282 283 284 285 286 287 288 289 290 292 293 293 293 294

296 296 296 298 299 299 300 300 314

315 315 315

XlI CONTENTS

Inorganic chemicals 315 Organic acids and their salts 315 Antioxidants 316 Antibiotics 316 Cured and smoked foods 317 Nitrite and nitrate curing 317 Colour and the curing process 317 Bacterial spoilage 319 Cured fish 320 Smoking 320

Fermented foods 321 Cheese 322 General requirements for cheese film wrappings 324 Yoghurt 325 Fermented meat and fish products 327 Vinegars, pickles, sauces and dressings 328 Other fermented products 330

Fats and oils 331 Spoilage mechanisms 331 Packaging requirements 332

References 334

13 Juices, soft drinks and alcoholic beverages 335 Fruit juices and beverages 335

Components and characteristics 336 Spoilage and its prevention 337 Packaging requirements 339

Beers and ales 342 Spoilage 342 Packaging materials 343

Cider 344 Wine 344

Packaging requirements 345 Distilled spirits 346 References 346

14 Developing packs for food 347 The product life cycle 347 Planning for change 350 Basic considerations for package development 350

Package structural development 351 Packaging coordination 353 Graphics 354 Packaging-line engineering 354 Cost of development 355

Developing a domestic food packaging for an export market 355 References 356

15 The economics of primary packaging 357 Cost comparisons 357 The economics of the glass primary package 359

Factors affecting cost 361 The economics of cans and canning 365

Economics of making tins 366 The ideal package shape for economy 366 Getting the most. out of available material 367 The total pack concept 368

CONTENTS

Costing tinplate packages for food worldwide Food canning worldwide Semi-scale production

The economics of cartons Board selection: the economic considerations Board selection for containment, compatibility and protection Board selection for efficient running on a packaging line Board selection for appearance and print quality

The economics of packaging with flexible materials Economics of plastics moulded packs Injection mouldings Thermoforming Compression mouldings

References

16 Using barrier materials efficiently Transmission of gases and vapours through barrier materials

Theory The variable factors associated with permeability measurements Estimating the type of barrier required Protection of a moisture-sensitive product Packaging barriers and their relation to moisture changes in foods The measurement of gas transmission rate Measurement of water vapour transmission

Pests Insect infestation Rats and mice

The compatibility of foods with their packaging Volatiles Non-volatiles

References

17 Specification and quality control What is quality? Quality control

Process sequence control Measurement, the assessment of quality

Measurement used for quality aspects Sampling

Factors affecting quality in packaging Package performance Quality measurement and control of cartons Quality control in a glass container factory Quality checks on corrugated cases

Quality assurance References Further reading

18 Evaluation and testing of transport packages Methods of evaluation Journey hazards

Distribution systems Obtaining data on journey hazards

The effect of environment on packages Impacts

xiii

369 370 371 374 376 378 379 381 384 386 388 388 389 389

390 390 392 395 402 405 407 413 416 417 417 421 421 422 423 425

426 427 429 429 430 433 435 437 437 438 447 452 458 463 463

464 464 464 464 465 466 467

xiv

Crushing The vibration hazard

Package test equipment Mechanical testing Climatic testing

Methods of using tests Performance test schedules

References

Appendices

CONTENTS

Appendix 1 European packaging legislation Appendix 2 USA legislation

Index

469 470 471 471 472 473 474 476

477

477 491

493