Food Processing Technology: Principles and Practice (Woodhead Publishing Series in Food Science, Technology and Nutrition)

Food Processing Technology: Principles and Practice, Fourth Edition, has been updated and extended to include the many developments that have taken place since the third edition was published. The new edition includes an overview of the component subjects in food science and technology, processing stages, important aspects of food industry management not otherwise considered (e.g. financial management, marketing, food laws and food industry regulation), value chains, the global food industry, and over-arching considerations (e.g. environmental issues and sustainability). In addition, there are new chapters on industrial cooking, heat removal, storage, and distribution, along with updates on all the remaining chapters. This updated edition consolidates the position of this foundational book as the best single-volume introduction to food manufacturing technologies available, remaining as the most adopted standard text for many food science and technology courses. Updated edition completely revised with new developments on all the processing stages and aspects of food industry management not otherwise considered (e.g. financial management, marketing, food laws, and food industry regulation), and more Introduces a range of processing techniques that are used in food manufacturing Explains the key principles of each process, including the equipment used and the effects of processing on micro-organisms that contaminate foods Describes post-processing operations, including packaging and distribution logistics Includes extra textbook elements, such as videos and calculations slides, in addition to summaries of key points in each chapter Front Cover Dedication Food Processing Technology Copyright Page Contents Biography Acknowledgements Introduction A brief history of food processing Pre-history to AD 1000 AD 1000–1800 1800–2000 Post-2000: the food industry today References About this book I. Basic Principles 1 Properties of food and principles of processing 1.1 Composition of foods 1.1.1 Carbohydrates 1.1.1.1 Sugars 1.1.1.2 Sugar syrups 1.1.1.3 Oligosaccharides 1.1.1.4 Polysaccharides 1.1.1.5 Starch 1.1.1.6 Modified starches 1.1.1.7 Cellulose 1.1.1.8 Polysaccharide gums 1.1.2 Lipids 1.1.2.1 Phospholipids 1.1.2.2 Sterols 1.1.2.3 Fat replacers 1.1.3 Proteins 1.1.3.1 Functional properties 1.1.3.2 Antinutritional factors and food allergens 1.1.4 Water 1.1.5 Vitamins 1.1.6 Minerals 1.1.7 Colourants and pigments 1.1.8 Antioxidants 1.1.9 Preservatives 1.1.10 Natural toxicants 1.2 Physical properties 1.2.1 Density and specific gravity 1.2.2 Viscosity 1.2.3 Surface activity 1.2.3.1 Emulsions 1.2.3.2 Foams 1.2.4 Water activity 1.3 Biochemical properties 1.3.1 Acids, bases and pH 1.3.2 Redox potential 1.4 Food quality, safety, spoilage and shelf-life 1.4.1 Quality attributes 1.4.1.1 Sensory characteristics 1.4.1.2 Appearance and colour 1.4.1.3 Taste and flavour 1.4.1.4 Texture 1.4.1.5 Nutritional quality 1.4.2 Food safety 1.4.2.1 Bacteria 1.4.2.2 Mycotoxins 1.4.2.3 Viruses 1.4.2.4 Parasites 1.4.3 Hurdle concepts 1.4.4 Spoilage 1.4.4.1 Temperature 1.4.4.2 Physical changes 1.4.4.3 Moisture migration 1.4.4.4 Biochemical changes 1.4.4.5 Microbiological changes 1.4.4.6 Bacteria 1.4.4.7 Fungi 1.4.4.8 Enzymic reactions 1.4.5 Shelf-life assessment 1.4.6 Date marking 1.4.7 Food traceability and authenticity 1.5 Quality assurance: management of food quality and safety 1.5.1 HACCP and prerequisite programmes 1.5.1.1 Hazard analysis 1.5.1.2 Critical control points, good practice guidelines and prerequisite programmes 1.5.1.3 Monitoring and verification 1.5.2 Quality and safety management systems 1.6 Process monitoring and control 1.6.1 Sensors 1.6.1.1 Biosensors 1.6.2 Process analytical technology and quality by design 1.6.2.1 Spectroscopic sensors 1.6.2.2 Other methods for nondestructive quality analysis of foods 1.6.3 Process controllers 1.6.3.1 Batching and blending 1.6.3.2 Software developments 1.6.4 Neural networks and fuzzy logic 1.6.4.1 Fuzzy logic 1.6.4.2 Robotics 1.7 Hygienic design and cleaning of processing facilities and equipment 1.7.1 Hygienic design 1.7.1.1 Construction 1.7.1.2 Layout 1.7.1.3 Utility services 1.7.1.4 Equipment 1.7.2 Cleaning and sanitation 1.7.2.1 Disinfection 1.7.2.2 Methods of cleaning 1.8 Engineering principles 1.8.1 Mass transfer and mass balances 1.8.1.1 Mass balances 1.8.2 Fluid flow 1.8.2.1 Fluid flow through fluidised beds 1.8.3 Phase and glass transitions 1.8.3.1 Steam generation 1.8.3.2 Glass transitions 1.8.4 Heat transfer 1.8.4.1 Sensible and latent heat 1.8.4.2 Energy balances 1.8.4.3 Types of heat transfer 1.8.4.3.1 Conduction 1.8.4.3.2 Convection 1.8.4.3.3 Unsteady-state heat transfer by conduction and convection 1.8.4.3.4 Radiation 1.8.4.4 Effect of heat on microorganisms and enzymes 1.8.4.5 Effect of heat on nutritional and sensory characteristics of foods 1.8.4.6 Losses of nutrients References Recommended further reading Composition of Foods, Physical and Biochemical Properties Food Quality and Safety Management, Process Monitoring and Control, Shelf-life, Traceability Hygienic Design and Cleaning of Processing Facilities and Equipment Energy and Water Saving Engineering Principles II. Ambient Temperature Processing 2 Raw material preparation 2.1 Cooling crops and carcasses 2.1.1 Theory 2.1.2 Hydrocooling equipment 2.1.2.1 Cooling carcasses 2.2 Cleaning foods 2.2.1 Wet cleaning 2.2.2 Dry methods of cleaning 2.2.2.1 Magnetic and electrostatic separators 2.2.2.2 Screens and shape sorters 2.2.2.3 Colour and imaging machines 2.3 Sorting and grading 2.3.1 Shape and size sorting 2.3.1.1 Theory 2.3.1.2 Equipment 2.3.2 Weight sorting 2.3.3 Colour and machine vision sorting and grading systems 2.3.4 Other types of grader 2.4 Peeling References Recommended further reading 3 Extraction and separation of food components 3.1 Centrifugation 3.1.1 Theory 3.1.2 Equipment 3.1.2.1 Separation of immiscible liquids Centrifugal clarifiers Desludging, decanting or dewatering centrifuges 3.2 Filtration 3.2.1 Theory 3.2.2 Equipment 3.2.2.1 Pressure filters 3.2.2.2 Vacuum filters 3.3 Expression 3.3.1 Theory 3.3.2 Equipment 3.3.2.1 Batch presses 3.3.2.2 Continuous presses 3.4 Extraction using solvents 3.4.1 Theory 3.4.2 Solvents 3.4.2.1 Supercritical carbon dioxide 3.4.3 Equipment 3.4.3.1 CO2 extractors Single-stage solvent extractors 3.4.3.2 Multistage solvent extractors Continuous extractors 3.5 Membrane separation 3.5.1 Theory 3.5.1.1 Hydrostatic pressure systems 3.5.2 Equipment and applications 3.5.2.1 Reverse osmosis 3.5.2.2 Nanofiltration, ultrafiltration and microfiltration 3.5.2.3 Pervaporation 3.5.3 Types of membrane systems 3.5.3.1 Ion exchange and electrodialysis 3.6 Effects on foods and microorganisms 3.7 Effect on microorganisms References Recommended further reading Centrifugation Filtration Extraction Membrane separation and concentration 4 Size reduction 4.1 Size reduction of solid foods 4.1.1 Theory 4.1.2 Equipment 4.1.2.1 Cutting, slicing dicing, mincing, shredding and flaking equipment 4.1.2.2 Milling equipment Ball mills Disc (or plate) mills 4.1.2.3 Hammer mills Jet pulverising mills 4.1.2.4 Roller mills Pulping equipment 4.1.3 Developments in size reduction technology 4.1.4 Effect on foods 4.1.4.1 Sensory characteristics 4.1.4.2 Nutritional value 4.1.5 Effect on microorganisms 4.2 Size reduction in liquid foods 4.2.1 Theory 4.2.2 Emulsifying agents and stabilisers 4.2.3 Equipment 4.2.3.1 High-speed mixers 4.2.3.2 Hydroshear homogeniser 4.2.3.3 Membrane emulsification 4.2.3.4 Pressure homogenisers 4.2.3.5 Rotor-stator homogenisers and colloid mills 4.2.3.6 Ultrasonic homogenisers 4.2.4 Effect on foods 4.2.4.1 Viscosity or texture 4.2.4.2 Colour, aroma and nutritional value 4.2.5 Effect on microorganisms References Recommended further reading 5 Mixing, forming and coating 5.1 Mixing 5.1.1 Theory of solids mixing 5.1.2 Theory of liquids mixing 5.1.3 Equipment 5.1.3.1 Mixers for dry powders or particulate solids 5.1.3.2 Mixers for low- or medium-viscosity liquids 5.1.3.3 Mixers for high-viscosity liquids and pastes 5.1.4 Effect on foods and microorganisms 5.2 Forming 5.2.1 Bread moulders 5.2.2 Pie, tart and biscuit formers 5.2.3 Confectionery moulders and depositors 5.2.3.1 Moulding equipment 5.2.3.2 Extruded confectionery ‘ropes’ 5.2.3.3 Depositors 5.2.4 Cold extrusion 5.3 Coating foods 5.3.1 Coating materials 5.3.1.1 Chocolate and compound coatings 5.3.1.2 Batters, powders and breadcrumbs 5.3.2 Equipment 5.3.2.1 Enrobers 5.3.2.2 Dusting or breading equipment 5.3.2.3 Pan coating 5.3.2.4 Hard coatings 5.3.2.5 Soft coatings 5.3.2.6 Chocolate coating 5.3.3 Microencapsulation 5.3.3.1 Liposomes 5.3.3.2 Nanoparticles 5.3.3.3 Packaging applications 5.3.4 Edible barrier coatings References Recommended further reading Mixing Forming and coating Encapsulation 6 Food biotechnology 6.1 Fermentation technology 6.1.1 Theory 6.1.1.1 Batch culture 6.2.1.1 Continuous culture 6.2.1 Equipment 6.2.1.1 Submerged cultures Temperature control pH control Dissolved oxygen control Agitation control Foaming control Control of medium addition and fermentation time Displays and data logging Automatic control of fermenters 6.2.1.2 Solid substrate fermentations Control of temperature and aeration Moisture content 6.2.2 Commercial food fermentations 6.2.2.1 Alcohol production 6.2.2.2 Cereal products 6.2.2.3 Dairy products 6.2.2.4 Meat and fish products 6.2.2.5 Mycoprotein 6.2.2.6 Pickled vegetable products 6.2.2.7 Soybean products 6.2.3 Effects on foods 6.2.3.1 Sensory characteristics 6.2.3.2 Nutritional value 6.2.3.3 Safety 6.2 Microbial enzymes 6.2.1 Novel enzyme technologies 6.3 Bacteriocins and antimicrobial ingredients 6.3.1 Chitin and chitosans 6.4 Functional foods 6.4.1 Health and nutrition claims and regulation 6.4.2 Probiotic, prebiotic and synbiotic foods 6.5 Genetic modification 6.5.1 GM food crops 6.5.1.1 Legislation and public perceptions of GM foods 6.5.1.2 Safety testing 6.5.2 Genetically modified microorganisms (GMMs) and their products 6.5.3 Marker-assisted selection 6.6 Nutritional genomics References Recommended further reading Food fermentations Enzymes Functional foods GMOs Nutritional genomics 7 Minimal processing methods 7.1 Introduction 7.2 High-pressure processing 7.2.1 Introduction 7.2.2 Theory 7.2.3 Equipment and operation 7.2.3.1 Operation 7.2.4 Process developments 7.2.4.1 Pulsed HPP systems 7.2.4.2 Combinations of HPP and other minimal processing technologies 7.2.5 Packaging 7.2.6 Effects on food components 7.2.7 Effects on enzymes 7.2.8 Inactivation of microorganisms 7.2.8.1 Effect on parasites and viruses 7.2.9 Regulation 7.2.10 Applications 7.2.10.1 Meat products 7.2.10.2 Seafoods 7.2.10.3 Dairy products 7.2.10.4 Fruit and vegetable products 7.3 Irradiation 7.3.1 Introduction 7.3.2 Theory 7.3.2.1 Dose distribution 7.3.3 Equipment 7.3.4 Measurement of radiation dose 7.3.5 Detection of irradiated foods 7.3.6 Regulation 7.3.7 Applications 7.3.8 Effects on foods 7.3.8.1 Induced radioactivity and radiolytic products 7.3.8.2 Effects on nutritional and sensory properties 7.3.9 Effects on microorganisms 7.3.10 Effects on packaging 7.4 Ozone 7.4.1 Ozone production and use 7.4.2 Antimicrobial activity 7.4.3 Processing applications 7.4.3.1 Fruits and vegetables 7.4.3.2 Animal products 7.4.3.3 Dry foods 7.4.3.4 Packaging materials and equipment 7.4.3.5 Combined treatments 7.4.4 Limitations and potential toxicity 7.5 Pulsed electric field processing 7.5.1 Theory 7.5.2 Equipment and operation 7.5.3 Effects on microorganisms, enzymes and food components 7.5.4 Combinations of PEF and other treatments 7.5.5 Regulation 7.6 Pulsed light and ultraviolet light 7.6.1 Theory 7.6.2 Equipment 7.6.3 Effect on microorganisms, enzymes and food components 7.6.4 Regulation and use 7.7 Power ultrasound 7.7.1 Theory 7.7.2 Processing equipment 7.7.3 Effect on microorganisms, enzymes and food components 7.8 Other minimal processing methods under development 7.8.1 Dense-phase carbon dioxide 7.8.1.1 Effects on microorganisms and enzymes 7.8.1.2 Equipment 7.8.1.3 Applications and effects on foods 7.8.2 Electric arc discharges and cold plasma 7.8.2.1 High-voltage arc discharge processing 7.8.2.2 Cold plasma 7.8.3 Oscillating magnetic fields 7.8.3.1 Equipment 7.8.4 Pulsed X-rays References Recommended further reading Minimal processes High-pressure processing Irradiation Ozone PEF Pulsed/UV light Ultrasound Minimal processes under development III. Processing by Application of Heat 8 Overview of heat processing 8.1 Sources of heat and methods of application to foods 8.1.1 Direct heating methods 8.1.2 Indirect-heating methods 8.2 Energy use and methods to reduce energy consumption 8.2.1 Energy efficiency audits 8.3 Types of heat exchanger References Recommended further reading Energy use and energy audits Heat transfer equipment III.A Heat Processing Using Steam or Hot Water 9 Blanching 9.1 Theory 9.2 Equipment 9.2.1 Steam blanchers 9.2.2 Hot-water blanchers 9.2.3 Newer blanching methods 9.3 Effect on foods 9.4 Effect on microorganisms References Recommended further reading 10 Industrial cooking 10.1 Cooking using moist heat 10.1.1 Equipment 10.1.1.1 Jacketed kettles 10.1.1.2 Bratt pans 10.1.1.3 Steamers 10.2 Sous vide cooking 10.2.1 Theory 10.2.2 Processing 10.2.2.1 Quality assurance 10.2.3 Effects on foods 10.2.3.1 Meat 10.2.3.2 Fish and shellfish 10.2.3.3 Fruits and vegetables 10.3 Cooking using dry heat 10.3.1 Equipment 10.3.1.1 Stir fryers 10.3.1.2 Ovens References Recommended further reading 11 Pasteurisation 11.1 Theory 11.2 Equipment 11.2.1 Pasteurisation of packaged foods 11.2.2 Pasteurisation of unpackaged liquids 11.3.1 Novel pasteurisation methods 11.3 Effects on foods References Recommended further reading 12 Heat sterilisation 12.1 In-container sterilisation 12.1.1 Theory 12.1.1.1 Heat resistance of microorganisms 12.1.1.2 Rate of heat penetration 12.1.1.3 Process validation 12.1.1.4 Calculation of process times 12.1.1.5 Formula (or mathematical) method 12.1.1.6 Improved general (graphical) method 12.1.2 Retorting 12.1.2.1 Heating by saturated steam 12.1.2.2 Heating by hot water 12.1.2.3 Heating by flames 12.1.3 Equipment 12.1.3.1 Control of retorts 12.2 Ultrahigh-temperature/aseptic processes 12.2.1 Theory 12.2.2 Processing 12.2.3 Equipment 12.2.3.1 Direct heating methods 12.2.3.2 Indirect heating methods 12.2.3.3 Other heating methods 12.3 Effects on foods 12.3.1 Canning 12.3.1.1 Colour 12.3.1.2 Flavour and aroma 12.3.1.3 Texture 12.3.1.4 Nutritional value 12.3.2 UHT processing 12.3.2.1 Colour and flavour 12.3.2.2 Texture 12.3.2.3 Nutritional value References Recommended further reading 13 Evaporation and distillation 13.1 Evaporation 13.1.1 Theory 13.1.1.1 Temperature difference between the steam and boiling liquid 13.1.1.2 Boundary films 13.1.1.3 Deposits on heat transfer surfaces 13.1.1.4 Mass and heat balances 13.1.2 Improving the economics of evaporation 13.1.2.1 Reducing energy consumption 13.1.2.2 Multiple effect evaporation 13.1.2.3 Vapour recompression 13.1.2.4 Reducing losses of concentrate or product quality 13.1.2.5 Equipment 13.1.2.6 Natural circulation evaporators 13.1.2.7 Forced circulation evaporators Plate evaporators Tubular evaporators Mechanical (or agitated) thin-film evaporators 13.1.2.8 Condensers 13.1.2.9 Control of evaporators 13.1.3 Effect on foods and microorganisms 13.2 Distillation 13.2.1 Theory 13.2.2 Equipment 13.2.3 Effects on foods and microorganisms References Recommended further reading Evaporation Distillation III.B Processing Using Hot Air or Heated Surfaces 14 Dehydration 14.1 Theory 14.1.1 Drying using heated air 14.1.1.1 Psychrometrics 14.1.1.2 Mechanism of drying Constant rate period Falling rate period Calculation of drying rate 14.1.2 Drying using heated surfaces 14.2 Equipment 14.2.1 Hot-air dryers 14.2.1.1 Bin dryers 14.2.1.2 Cabinet (or tray) dryers 14.2.1.3 Conveyor dryers 14.2.1.4 Explosion puff drying 14.2.1.5 Fluidised bed dryers 14.2.1.6 Impingement dryers 14.2.1.7 Kiln dryers 14.2.1.8 Pneumatic dryers 14.2.1.9 Rotary dryers 14.2.1.10 Spray dryers 14.2.1.11 Encapsulation 14.2.1.12 Sun and solar drying 14.2.1.13 Tunnel dryers 14.2.1.14 Ultrasonic and acoustic dryers 14.2.2 Heated-surface (or contact) dryers 14.2.2.1 Ball dryer 14.2.2.2 Drum (or roller) dryers 14.2.2.3 Vacuum band and vacuum shelf dryers 14.2.2.4 Vertically agitated dryers 14.3 Control of dryers 14.4 Rehydration 14.5 Effects on foods and microorganisms 14.5.1 Sensory properties 14.5.1.1 Texture 14.5.1.2 Flavour and aroma 14.5.1.3 Colour 14.5.2 Nutritional value 14.5.3 Effects on microorganisms References Recommended further reading 15 Smoking 15.1 Theory 15.1.1 Constituents in smoke 15.1.1.1 Flavour components 15.1.1.2 Preservative components 15.1.2 Tasteless smoke 15.1.3 Liquid smoke 15.2 Processing 15.2.1 Equipment 15.3 Effects on foods 15.3.1 Organoleptic quality 15.3.2 Nutritional value and health concerns 15.4 Effects on microorganisms References Recommended further reading 16 Baking and roasting 16.1 Theory 16.1.1 Baking conditions 16.1.2 Type of food 16.2 Equipment 16.2.1 Energy-saving features 16.2.2 Batch and semicontinuous ovens 16.2.3 Continuous ovens 16.2.4 Control of ovens 16.3 Effects on foods and microorganisms 16.3.1 Changes to sensory characteristics 16.3.1.1 Texture 16.3.1.2 Flavour and aroma 16.3.1.3 Colour 16.3.2 Changes to nutritional value 16.3.3 Effects on microorganisms 16.3.3.1 Packaging References Recommended further reading 17 Extrusion cooking 17.1 Theory 17.1.1 Properties of ingredients 17.1.2 Extruder operating characteristics 17.2 Equipment 17.2.1 Single-screw extruders 17.2.2 Twin-screw extruders 17.2.3 Control of extruders 17.3 Applications 17.3.1 Confectionery products 17.3.2 Cereal products 17.3.2.1 Snackfoods 17.3.2.2 Breakfast cereals 17.3.2.3 Crispbread 17.3.3 Protein-based foods 17.3.3.1 Texturised vegetable protein (TVP) 17.3.3.2 Weaning foods 17.3.3.3 Meat and fish products 17.4 Effect on foods and microorganisms 17.4.1 Sensory characteristics 17.4.1.1 Texture 17.4.1.2 Flavour 17.4.1.3 Colour 17.4.2 Nutritional value 17.4.2.1 Starch and oligosaccharides 17.4.2.2 Proteins 17.4.2.3 Fats 17.4.2.4 Vitamins and minerals 17.4.3 Effects on microorganisms References Recommended further reading III.C Heat Processing Using Hot Oils 18 Frying 18.1 Theory 18.1.1 Heat and mass transfer 18.1.1.1 Heat transfer 18.1.1.2 Mass transfer 18.1.2 Frying time and temperature 18.1.3 Oil absorption 18.1.3.1 Oil turnover 18.2 Equipment 18.2.1 Atmospheric fryers 18.2.1.1 Oil reduction systems 18.2.2 Vacuum and pressure fryers 18.2.3 Control of fryer operation, oil filtration and heat recovery 18.2.3.1 Oil filtration 18.2.3.2 Heat recovery and control of emissions 18.3 Types of oils used for frying 18.4 Effects of frying on oils 18.5 Effects of frying on foods 18.5.1 Changes to food texture, colour and flavour 18.5.2 Nutritional changes 18.6 Effects of frying on microorganisms References Recommended further reading III.D Processing by Direct and Radiated Energy 19 Dielectric, ohmic and infrared heating 19.1 Dielectric heating 19.1.1 Theory 19.1.2 Equipment 19.1.2.1 Microwave heaters 19.1.2.2 Radio frequency heaters 19.1.3 Applications 19.1.3.1 Dehydration 19.1.3.2 Baking 19.1.3.3 Thawing, melting and tempering 19.1.3.4 Other applications 19.1.4 Effects on foods and microorganisms 19.2 Ohmic heating 19.2.1 Theory 19.2.2 Equipment and applications 19.2.3 Effects on foods and microorganisms 19.3 Infrared heating 19.3.1 Theory 19.4.1 Equipment and applications 19.4.2 Effects on foods and microorganisms References Recommended further reading Dielectric heating Ohmic heating Infrared heating IV. Processing by Removal of Heat 20 Heat removal by refrigeration 20.1 Theory 20.1.1 Refrigerants and cryogens 20.1.1.1 Refrigerants 20.1.1.2 Cryogens 20.1.2 The refrigeration cycle 20.2.1 Magnetic refrigeration 20.2 Equipment 20.2.1 Control of mechanical refrigerators 20.2.2 Temperature monitoring 20.2.2.1 Time–temperature indicators 20.2.2.2 Types of TTIgs 20.2.2.3 Enzymatic TTIgs 20.2.2.4 Polymer-based TTIgs 20.2.2.5 Diffusion-based TTIgs 20.2.2.6 Microbial TTIgs 20.2.2.7 Photochemical TTIgs 20.2.2.8 RFID and other TTIgs References Recommended further reading Refrigeration and cryogens Time–temperature indicators 21 Chilling 21.1 Theory 21.2 Equipment 21.2.1 Mechanical chillers 21.2.2 Cryogenic chilling 21.2.3 Other methods of chilling 21.3 Applications to processed foods 21.3.1 Cook–chill systems 21.4 Effects on foods 21.5 Effects on microorganisms References Recommended further reading 22 Freezing 22.1 Theory 22.1.1 Ice crystal formation 22.1.2 Solute concentration 22.1.3 Calculation of freezing time 22.1.4 Thawing 22.2 Equipment 22.2.1 Mechanical freezers 22.2.1.1 Cooled air freezers 22.2.1.2 Cooled liquid freezers 22.2.1.3 Cooled-surface freezers 22.2.2 Cryogenic freezers 22.2.3 Developments in freezing technologies 22.2.3.1 High-pressure freezing and thawing 22.2.3.2 Hydrofluidisation 22.2.3.3 Ultrasound freezing 22.2.3.4 Magnetic freezing 22.2.3.5 Dehydrofreezing 22.2.3.6 Electrostatic field-assisted freezing and radiofrequency freezing 22.2.3.7 Cryoprotectants 22.2.4 Thawing 22.3 Effects on foods 22.3.1 Freezing 22.3.1.1 Volume changes 22.3.2 Frozen storage 22.3.2.1 Degradation of pigments 22.3.2.2 Loss of vitamins 22.3.2.3 Enzyme activity 22.3.2.4 Oxidation of lipids Recrystallisation 22.3.3 Thawing 22.4 Effects on microorganisms References Recommended further reading 23 Freeze drying and freeze concentration 23.1 Freeze drying 23.1.1 Theory 23.1.1.1 Rate of heat transfer 23.1.1.2 Rate of mass transfer 23.1.2 Equipment 23.1.2.1 Contact (or conduction) freeze dryers 23.2.1.2 Radiant freeze dryers 23.1.2.3 Microwave-assisted freeze dryers 23.1.3 Effects on foods and microorganisms 23.2 Freeze concentration 23.2.1 Theory 23.2.2 Equipment 23.2.3 Effects on foods and microorganisms References Recommended further reading Freeze drying Freeze concentration V. Postprocessing Operations 24 Packaging 24.1 Theory 24.1.1 Factors affecting the selection of a packaging material 24.1.1.1 Light 24.1.1.2 Temperature 24.1.1.3 Moisture and gases 24.1.1.4 Grease resistance 24.1.1.5 Microorganisms, insects, animals and soils 24.1.1.6 Mechanical strength 24.1.1.7 Tamper-evident/resistant features 24.1.2 Interactions between packaging and foods 24.2 Types of packaging materials 24.2.1 Textiles and wood 24.2.2 Metal 24.2.2.1 Three-piece cans 24.2.2.2 Two-piece cans 24.2.2.3 Aerosol cans 24.2.2.4 Other metal packaging 24.2.3 Glass 24.2.4 Flexible films 24.2.4.1 Single films 24.2.4.2 Cellulose 24.2.4.3 Ethylene vinyl acetate (EVA) or alcohol (EVOH) 24.2.4.4 Polyamides (PA or nylons) 24.2.4.5 Polyethylene (commonly ‘polythene’) 24.2.4.6 Polyethylene naphthalene (PEN) 24.2.4.7 Polyethylene terephthalate (PET) 24.2.4.8 Polypropylene (PP) 24.2.4.9 Polystyrene (PS) and high-impact PS (HIPS) 24.2.4.10 Polyvinyl chloride (PVC) 24.2.4.11 Polyvinylidene chloride (PVdC) 24.2.4.12 Coated films 24.2.4.13 Laminated films 24.2.4.14 Coextruded films 24.2.5 Rigid and semirigid plastic containers 24.2.6 Paper and board 24.2.6.1 Types of papers 24.2.6.2 Coated papers 24.2.6.3 Paperboard cartons 24.2.6.4 Adhesives 24.2.6.5 Moulded paperpulp containers 24.2.7 Combined packaging systems 24.3 Packaging materials for modified atmosphere packaging (MAP) 24.3.1 Effect on microorganisms 24.4 Printing 24.4.1 Bar codes and other markings 24.5 Packaging developments 24.5.1 Edible and biodegradable materials 24.5.1.1 Edible protective superficial layers 24.5.2 Nanotechnology 24.5.3 Active and intelligent packaging 24.5.3.1 Moisture control 24.5.3.2 Gas control 24.5.3.3 Antimicrobial packaging and freshness indicators 24.5.3.4 Temperature control 24.5.3.5 Tracing, tracking and tamper-evident packaging 24.6 Environmental and regulatory considerations 24.6.1 Reductions in use of energy and materials 24.6.2 Reduction in weight of materials per pack (light-weighting) 24.6.3 Re-use and recycling 24.6.3.1 Re-use 24.6.3.2 Recycling 24.6.3.3 Composting 24.6.3.4 Incineration and landfill 24.6.3.5 Life-cycle analysis 24.6.3.6 Other regulatory aspects References Recommended further reading Packaging Modified atmosphere packaging Novel packaging Labelling Environmental aspects 25 Filling and sealing of containers 25.1 Rigid and semirigid containers 25.1.1 Filling 25.1.1.1 Liquid fillers 25.1.1.2 Solids filling 25.1.2 Sealing 25.1.2.1 Glass and plastic containers 25.1.2.2 Metal containers 25.1.2.3 Paperboard cases and cartons 25.2 Flexible containers 25.2.1 Form–fill–seal (FFS) equipment 25.2.2 Tray, pot and carton sealing 25.3 Twist-wrapping 25.4 Shrink-wrapping and stretch-wrapping 25.5 Tamper-evident and tamper-resistant closures 25.6 Labelling 25.7 Checkweighing 25.8 Metal detection References Recommended further reading Equipment Closures Labelling Metal detection 26 Materials handling, storage and distribution 26.1 Materials handling 26.1.1 Solids handling methods 26.1.1.1 Conveyors 26.1.1.2 Elevators 26.1.2 Liquid handling methods 26.1.2.1 Pumps 26.1.2.2 Valves 26.2 Storage 26.2.1 Ambient storage 26.2.2 Temperature-controlled storage 26.2.2.1 Cold storage 26.2.2.2 Cold storage of meat 26.2.2.3 Cold storage equipment and operation 26.2.2.4 Frozen storage 26.2.3 Modified and controlled atmosphere storage 26.2.3.1 MAS/CAS equipment 26.3 Logistics and control of storage and distribution 26.3.1 Factory warehousing for ingredients and products 26.3.1.1 Warehouse operation 26.3.2 Distribution warehousing References Recommended further reading Materials handling Storage Logistics Index Annex A: Food components A.1 Structure of food macromolecules A.1.1 Carbohydrates A.1.1.1 Sugars A.1.1.2 Glycogen and starch A.1.1.3 Cellulose A.1.1.4 Polysaccharide gums A.1.2 Lipids A.1.2.1 Phospholipids A.1.3 Amino acids and proteins A.2 Vitamins and minerals A.3 Functional components of foods References Annex B: Micro-organisms B.1 Pathogens B.1.1 Aeromonas spp. B.1.2 Bacillus cereus B.1.3 Brucella spp. B.1.4 Campylobacter spp. and Arcobacter spp. B.1.4.1 Clostridium botulinum B.1.4.2 Clostridium perfringens B.1.5 Enteropathogenic Escherichia coli B.1.5.1 Listeria monocytogenes B.1.5.2 Mycobacterium paratuberculosis B.1.6 Plesiomonas spp. B.1.7 Salmonella spp. B.1.8 Shigella spp. B.1.9 Staphylococcus aureus B.1.10 Vibrio spp. B.1.11 Yersinia enterocolitica B.2 Viruses B.3 Enzymes from genetically modified (GM) microorganisms B.4 Food fermentations References Annex C: Units and conversions C.1 Units C.2 Conversions C.3 Mesh sizes Annex D: Glossary, acronyms, symbols D.1 Glossary D.2 List of acronyms D.3 Symbols Back Cover