Food Packaging Technology

368 Pages·2003·2.53 MB·English

Food Packaging Technology

Packaging Technology Series

Series Editor: Geoff A. Giles, Global Pack Management, GlaxoSmithKline,
London.

A series which presents the current state of the art in chosen sectors of the
packaging industry. Written at professional and reference level, it is directed
at packaging technologists, those involved in the design and development of
packaging, users of packaging and those who purchase packaging. The series
will also be of interest to manufacturers of packaging machinery.

Titles in the series:

Design and Technology of Packaging Decoration for the
Consumer Market
Edited by G.A. Giles

Materials and Development of Plastics Packaging for the
Consumer Market
Edited by G.A. Giles and D.R. Bain

Technology of Plastics Packaging for the Consumer Market
Edited by G.A. Giles and D.R. Bain

Canmaking for Can Fillers
Edited by T.A. Turner

PET Packaging Technology
Edited by D.W. Brooks and G.A. Giles

Food Packaging Technology
Edited by R. Coles, D. McDowell and M.J. Kirwan

Packaging Closures and Sealing Systems
Edited by N. Theobald

FOOD PACKAGING TECHNOLOGY

Edited by

RICHARD COLES
Consultant in Food Packaging, London

DEREK MCDOWELL
Head of Supply and Packaging Division
Loughry College, Northern Ireland

and

MARK J. KIRWAN
Consultant in Packaging Technology
London

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First published 2003

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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

CONTENTS
ix

6.10
Environmental profile
171

6.10.1
Reuse
171

6.10.2
Recycling
171

6.10.3
Reduction – lightweighting
172

6.11
Glass as a marketing tool
172

References
172

Further reading
173

7
Plastics in food packaging
174

MARK J. KIRWAN and JOHN W. STRAWBRIDGE

7.1
Introduction
174

7.1.1
Definition and background
174

7.1.2
Use of plastics in food packaging
175

7.1.3
Types of plastics used in food packaging
177

7.2
Manufacture of plastics packaging
178

7.2.1
Introduction to the manufacture of plastics packaging
178

7.2.2
Plastic film and sheet for packaging
179

7.2.3
Pack types based on use of plastic films, laminates etc.
183

7.2.4
Rigid plastic packaging
186

7.3
Types of plastic used in packaging
189

7.3.1
Polyethylene
189

7.3.2
Polypropylene (PP)
191

7.3.3
Polyethylene terephthalate (PET or PETE)
194

7.3.4
Polyethylene naphthalene dicarboxylate (PEN)
195

7.3.5
Polycarbonate (PC)
196

7.3.6
Ionomers
196

7.3.7
Ethylene vinyl acetate (EVA)
197

7.3.8
Polyamide (PA)
197

7.3.9
Polyvinyl chloride (PVC)
198

7.3.10
Polyvinylidene chloride (PVdC)
199

7.3.11
Polystyrene (PS)
200

7.3.12
Styrene butadiene (SB)
201

7.3.13
Acrylonitrile butadiene styrene (ABS)
201

7.3.14
Ethylene vinyl alcohol (EVOH)
201

7.3.15
Polymethyl pentene (TPX)
202

7.3.16
High nitrile polymers (HNP)
202

7.3.17
Fluoropolymers
203

7.3.18
Cellulose-based materials
203

7.3.19
Polyvinyl acetate (PVA)
204

7.4
Coating of plastic films – types and properties
205

7.4.1
Introduction to coating
205

7.4.2
Acrylic coatings
205

7.4.3
PVdC coatings
206

7.4.4
PVOH coatings
206

7.4.5
Low-temperature sealing coatings (LTSCs)
206

7.4.6
Metallising with aluminium
207

7.4.7
SiOx coatings
207

7.4.8
DLC (Diamond-like coating)
208

7.4.9
Extrusion coating with PE
208

x
CONTENTS

7.5
Secondary conversion techniques
208

7.5.1
Film lamination by adhesive
208

7.5.2
Extrusion lamination
210

7.5.3
Thermal lamination
211

7.6
Printing
211

7.6.1
Introduction to the printing of plastic films
211

7.6.2
Gravure printing
211

7.6.3
Flexographic printing
212

7.6.4
Digital printing
212

7.7
Printing and labelling of rigid plastic containers
212

7.7.1
In-mould labelling
212

7.7.2
Labelling
213

7.7.3
Dry offset printing
213

7.7.4
Silk screen printing
213

7.7.5
Heat transfer printing
213

7.8
Food contact and barrier properties
214

7.8.1
The issues
214

7.8.2
Migration
214

7.8.3
Permeation
215

7.8.4
Changes in flavour
216

7.9
Sealability and closure
217

7.9.1
Introduction to sealability and closure
217

7.9.2
Heat sealing
217

7.9.2.1
Flat jaw sealing
218

7.9.2.2
Crimp jaw conditions
219

7.9.2.3
Impulse sealing
220

7.9.2.4
Hot wheel sealing
220

7.9.2.5
Hot air sealers
221

7.9.2.6
Gas flame sealers
221

7.9.2.7
Induction sealing
221

7.9.2.8
Ultrasonic sealing
221

7.9.3
Cold seal
221

7.9.4
Plastic closures for bottles, jars and tubs
221

7.9.5
Adhesive systems used with plastics
222

7.10
How to choose
222

7.11
Retort pouch
224

7.11.1
Packaging innovation
224

7.11.2
Applications
225

7.11.3
Advantages and disadvantages
226

7.11.4
Production of pouches
227

7.11.5
Filling and sealing
228

7.11.6
Processing
229

7.11.7
Process determination
230

7.11.8
Post retort handling
231

7.11.9
Outer packaging
231

7.11.10
Quality assurance
232

7.11.11
Shelf life
232

7.12
Environmental and waste management issues
233

7.12.1
Environmental benefit
233

7.12.2
Sustainable development
233

7.12.3
Resource minimisation – lightweighting
233

CONTENTS
xi

7.12.4
Plastics manufacturing and life cycle assessment (LCA)
234

7.12.5
Plastics waste management
235

7.12.5.1
Introduction to plastics waste management
235

7.12.5.2
Energy recovery
236

7.12.5.3
Feedstock recycling
236

7.12.5.4
Biodegradable plastics
237

Appendices
238

References
239

Further reading
240

Websites
240

8
Paper and paperboard packaging
241

M.J. KIRWAN

8.1
Introduction
241

8.2
Paper and paperboard – fibre sources and fibre separation (pulping)
243

8.3
Paper and paperboard manufacture
245

8.3.1
Stock preparation
245

8.3.2
Sheet forming
245

8.3.3
Pressing
246

8.3.4
Drying
247

8.3.5
Coating
248

8.3.6
Reel-up
248

8.3.7
Finishing
248

8.4
Packaging papers and paperboards
248

8.4.1
Wet strength paper
249

8.4.2
Microcreping
249

8.4.3
Greaseproof
249

8.4.4
Glassine
249

8.4.5
Vegetable parchment
249

8.4.6
Tissues
250

8.4.7
Paper labels
250

8.4.8
Bag papers
250

8.4.9
Sack kraft
250

8.4.10
Impregnated papers
250

8.4.11
Laminating papers
251

8.4.12
Solid bleached board (SBB)
251

8.4.13
Solid unbleached board (SUB)
251

8.4.14
Folding boxboard (FBB)
252

8.4.15
White lined chipboard (WLC)
253

8.5
Properties of paper and paperboard
254

8.5.1
Appearance
254

8.5.2
Performance
254

8.6
Additional functional properties of paper and paperboard
255

8.6.1
Treatment during manufacture
255

8.6.1.1
Hard sizing
255

8.6.1.2
Sizing with wax
255

8.6.1.3
Acrylic resin dispersion
255

8.6.1.4
Fluorocarbon dispersion
255

8.6.2
Lamination
255

xii
CONTENTS

8.6.3
Plastic extrusion coating and laminating
256

8.6.4
Printing and varnishing
257

8.6.5
Post-printing roller varnishing/coating/laminating
258

8.7
Design for paper and paperboard packaging
258

8.8
Package types
259

8.8.1
Tea and coffee bags
259

8.8.2
Paper bags and wrapping paper
259

8.8.3
Sachets/pouches/overwraps
260

8.8.4
Multiwall paper sacks
262

8.8.5
Folding cartons
263

8.8.6
Liquid packaging cartons
265

8.8.7
Rigid cartons or boxes
267

8.8.8
Paper based tubes, tubs and composite containers
268

8.8.8.1
Tubes
268

8.8.8.2
Tubs
268

8.8.8.3
Composite containers
268

8.8.9
Fibre drums
268

8.8.10
Corrugated fibreboard packaging
269

8.8.11
Moulded pulp containers
272

8.8.12
Labels
273

8.8.13
Sealing tapes
275

8.8.14
Cushioning materials
276

8.8.15
Cap liners (wads) and diaphragms
276

8.9
Systems
277

8.10
Environmental profile
277

Reference
281

Further reading
281

Websites
281

9
Active packaging
282

BRIAN P.F. DAY

9.1
Introduction
282

9.2
Oxygen scavengers
284

9.2.1
ZERO2™ oxygen scavenging materials
288

9.3
Carbon dioxide scavengers/emitters
289

9.4
Ethylene scavengers
290

9.5
Ethanol emitters
292

9.6
Preservative releasers
293

9.7
Moisture absorbers
295

9.8
Flavour/odour adsorbers
296

9.9
Temperature control packaging
297

9.10
Food safety, consumer acceptability and regulatory issues
298

9.11
Conclusions
300

References
300

10
Modified atmosphere packaging
303

MICHAEL MULLAN and DEREK MCDOWELL

Section A
MAP gases, packaging materials and equipment
303

10.A1
Introduction
303

10.A1.1
Historical development
304

CONTENTS
xiii

10.A2
Gaseous environment
304

10.A2.1
Gases used in MAP
304

10.A2.1.1
Carbon dioxide
304

10.A2.1.2
Oxygen
305

10.A2.1.3
Nitrogen
305

10.A2.1.4
Carbon monoxide
305

10.A2.1.5
Noble gases
306

10.A2.2
Effect of the gaseous environment on the activity of bacteria,
yeasts and moulds
306

10.A2.2.1
Effect of oxygen
306

10.A2.2.2
Effect of carbon dioxide
307

10.A2.2.3
Effect of nitrogen
308

10.A2.3
Effect of the gaseous environment on the chemical,
biochemical and physical properties of foods
308

10.A2.3.1
Effect of oxygen
309

10.A2.3.2
Effects of other MAP gases
310

10.A2.4
Physical spoilage
311

10.A3
Packaging materials
311

10.A3.1
Main plastics used in MAP
312

10.A3.1.1
Ethylene vinyl alcohol (EVOH)
312

10.A3.1.2
Polyethylenes (PE)
312

10.A3.1.3
Polyamides (PA)
313

10.A3.1.4
Polyethylene terephthalate (PET)
313

10.A3.1.5
Polypropylene (PP)
313

10.A3.1.6
Polystyrene (PS)
314

10.A3.1.7
Polyvinyl chloride (PVC)
314

10.A3.1.8
Polyvinylidene chloride (PVdC)
314

10.A3.2
Selection of plastic packaging materials
315

10.A3.2.1
Food contact approval
315

10.A3.2.2
Gas and vapour barrier properties
315

10.A3.2.3
Optical properties
318

10.A3.2.4
Antifogging properties
318

10.A3.2.5
Mechanical properties
318

10.A3.2.6
Heat sealing properties
319

10.A4
Modified atmosphere packaging machines
319

10.A4.1
Chamber machines
319

10.A4.2
Snorkel machines
319

10.A4.3
Form-fill-seal tray machines
320

10.A4.3.1
Negative forming
320

10.A4.3.2
Negative forming with plug assistance
321

10.A4.3.3
Positive forming with plug assistance
321

10.A4.4
Pre-formed trays
323

10.A4.4.1
Pre-formed trays versus thermoformed trays
323

10.A4.5
Modification of the pack atmosphere
324

10.A4.5.1
Gas flushing
324

10.A4.5.2
Compensated vacuum gas flushing
324

10.A4.6
Sealing
325

10.A4.7
Cutting
325

10.A4.8
Additional operations
325

10.A5
Quality assurance of MAP
326

10.A5.1
Heat seal integrity
326

10.A5.1.1
Nondestructive pack testing equipment
328

xiv
CONTENTS

10.A5.1.2
Destructive pack testing equipment
328

10.A5.2
Measurement of transmission rate and permeability in packaging films
329

10.A5.2.1
Water vapour transmission rate and measurement
329

10.A5.2.2
Measurement of oxygen transmission rate
331

10.A5.2.3
Measurement of carbon dioxide transmission rate
331

10.A5.3
Determination of headspace gas composition
331

10.A5.3.1
Oxygen determination
331

10.A5.3.2
Carbon dioxide determination
331

Section B
Main food types
331

10.B1
Raw red meat
331

10.B2
Raw poultry
332

10.B3
Cooked, cured and processed meat products
333

10.B4
Fish and fish products
334

10.B5
Fruits and vegetables
335

10.B6
Dairy products
338

References
338

Index
340

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