Food Processing Technology

PART I - BASIC PRINCIPLES

1 Properties of foods

1.1 Physical properties

1.1.1 Density and specific gravity

1.1.2 Viscosity

1.1.3 Surface activity

1.1.4 Water activity

1.2 Biochemical properties

1.2.1 Acids, bases and pH

1.2.2 Redox potential

2.1 Principles of processing

2.2 Mass transfer and mass balances

2.3 Fluid flow

2.4 Phase and glass transitions

2.5 Heat transfer

2.5.1 Thermal properties of foods and other materials

2.5.2 Types of heat transfer

2.5.3 Types of heat exchangers

2.5.4 Effects of heat on micro-organisms

2.5.5 Effects of heat on food components

2.6 Linking unit operations to form processes
References
Recommended further reading

PART II: AMBIENT-TEMPERATURE PROCESSING

2 Raw material preparation

2.1 Cooling crops and carcasses

2.1.1 Theory

2.1.2 Hydrocooling equipment

2.2 Cleaning foods

2.2.1 Wet cleaning

2.2.2 Dry methods of cleaning

2.3 Sorting and grading

2.3.1 Shape and size sorting

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 and coring
References
Recommended further reading

3 Extraction and separation of food components

3.1 Centrifugation

3.1.1 Theory

3.1.2 Equipment

3.2 Filtration

3.2.1 Theory

3.2.2 Equipment

3.3 Expression

3.3.1 Theory

3.3.2 Equipment

3.4 Extraction using solvents

3.4.1 Theory

3.4.2 Solvents

3.4.3 Equipment

3.5 Membrane separation

3.5.1 Theory

3.5.2 Equipment and applications

3.5.3 Types of membrane systems

3.6 Effects on foods and micro-organisms
References
Recommended further reading

4 Size reduction

4.1 Size reduction of solid foods

4.1.1 Theory

4.1.2 Equipment

4.1.3 Developments in size reduction technology

4.1.4 Effects on foods

4.1.5 Effects on micro-organisms

4.2 Size reduction in liquid foods

4.2.1 Theory

4.2.2 Emulsifying agents and stabilisers

4.2.3 Equipment

4.2.4 Effects on foods

4.2.5 Effects on micro-organisms
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 Gas blending

5.1.4 Equipment

5.1.5 Effects on foods and micro-organisms

5.2 Forming

5.2.1 Bread moulders

5.2.2 Pie, tart and biscuit formers

5.2.3 Confectionery moulders and depositors

5.2.4 Cold extrusion

5.3 Coating foods

5.3.1 Coating materials

5.3.2 Equipment

5.3.3 Microencapsulation

5.3.4 Edible barrier coatings
References
Recommended further reading

6 Food biotechnology

6.1 Fermentation technology

6.1.1 Theory

6.1.2 Equipment for submerged and solid substrate fermentations

6.1.3 Examples of commercial food fermentations

6.1.4 Effects on foods

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 Probiotic, prebiotic and synbiotic foods

6.5 Genetic modification

6.5.1 GM food crops

6.5.2 Genetically modified micro-organisms (GMMs) and their products

6.5.3 Marker assisted selection

6.6 Nutritional genomics
References
Recommended further reading

7 Minimal processing

7.1 Introduction

7.2 High Pressure processing

7.2.1 Introduction

7.2.2 Theory

7.2.3 Equipment and operation

7.2.4 Process developments

7.2.5 Packaging

7.2.6 Effects on food components

7.2.7 Effects on enzymes

7.2.8 Inactivation of micro-organisms

7.2.9 Regulation

7.2.10 Applications

7.3 Power ultrasound

7.3.1 Theory

7.3.2 Processing equipment

7.3.3 Process developments

7.3.4 Effects on micro-organisms, enzymes and food components

7.4 Pulsed electric fields

7.4.1 Theory

7.4.2 Equipment

7.4.3 Effects on micro-organisms, enzymes and food components

7.4.4 Combinations of PEF and other treatments

7.5 Electric arc discharges and cold plasma

7.5.1 Theory

7.5.2 Equipment and operation

7.5.3 Effects on micro-organisms, enzymes and food components

7.6 Oscillating magnetic fields

7.6.1 Theory

7.6.2 Equipment and operation

7.6.3 Effects on micro-organisms, enzymes and food components

7.7 Pulsed light and ultraviolet light

7.7.1 Theory

7.7.2 Equipment

7.7.3 Effects on micro-organisms, enzymes and food components

7.7.4 Regulation and use

7.8 Pulsed X-rays

7.8.1 Theory

7.8.2 Equipment and operation

7.8.3 Effects on micro-organisms, enzymes and food components

7.9 Irradiation

7.9.1 Introduction

7.9.2 Theory

7.9.3 Equipment

7.9.4 Measurement of radiation dose

7.9.5 Detection of irradiated foods

7.9.6 Applications

7.9.7 Effects on foods

7.9.8 Effects on micro-organisms

7.9.9 Effects on packaging

7.10 Ozone

7.10.1 Ozone production and use

7.10.2 Antimicrobial activity

7.10.3 Processing applications

7.10.4 Limitations and potential toxicity

7.11 Dense-phase carbon dioxide

7.11.1 Theory

7.11.2 Equipment and operation

7.11.3 Effects on micro-organisms, enzymes and food components
References
Recommended further reading

PART III: PROCESSING BY APPLICATION OF HEAT
Processing using steam or water

8 Blanching

8.1 Theory

8.2 Equipment

8.2.1 Steam blanchers

8.2.2 Hot-water blanchers

8.2.3 Newer blanching methods

8.3 Effects on Foods

8.4 Effects on micro-organisms
References
Recommended further reading

9 Industrial cooking

9.1 Cooking using moist heat

9.1.1 Equipment

9.2 Sous-vide cooking

9.2.1 Theory

9.2.2 Processing

9.2.3 Effects on foods

9.3 Cooking using dry heat

9.3.1 Equipment
References
Recommended further reading

10 Pasteurisation

10.1 Theory

10.2 Equipment

10.2.1 Pasteurisation of packaged foods

10.2.2 Pasteurisation of unpackaged liquids

10.2.3 Novel pasteurisation methods

10.3 Effects on foods
References
Recommended further reading

11 Heat sterilisation

11.1 In-container sterilisation

11.1.1 Theory

11.1.2 Retorting

11.1.3 Equipment

11.2 Ultra high-temperature (UHT)/aseptic processes

11.2.1 Theory

11.2.2 Processing and equipment

11.2.3 Equipment

11.3 Effects on foods

11.3.1 Canning

11.3.2 UHT processing
References
Recommended further reading

12 Evaporation and distillation

12.1 Evaporation

12.1.1 Theory

12.1.2 Improving the economics of evaporation

12.1.3 Equipment

12.1.4 Effects on foods and micro-organisms

12.2 Distillation

12.2.1 Theory

12.2.2 Equipment

12.2.3 Effects on foods and micro-organisms
References
Recommended further reading

Processing using hot air or heated surfaces

13 Dehydration

13.1 Theory

13.1.1 Drying using heated air

13.1.2 Drying using heated surfaces

13.2 Equipment

13.2.1 Hot-air dryers

13.2.2 Heated-surface (or contact) dryers

13.3 Control of dryers

13.4 Rehydration

13.5 Effects on foods and micro-organisms

13.5.1 Sensory properties

13.5.2 Nutritional value

13.5.3 Effects on micro-organisms
References
Recommended further reading

14 Smoking

14.1 Theory

14.1.1 Constituents in smoke

14.1.2 Tasteless smoke

14.1.3 Liquid smoke

14.2 Processing

14.2.1 Equipment

14.3 Effects on foods

14.4 Effects on micro-organisms
References
Recommended further reading

15 Baking and roasting

15.1 Theory

15.2 Equipment

15.2.1 Batch and semi-continuous ovens and roasters

15.2.2 Continuous ovens and roasters

15.2.3 Control of ovens

15.3 Effects on foods

15.4 Effects on micro-organisms
References
Recommended further reading

16 Extrusion cooking

16.1 Theory

16.1.1 Properties of ingredients

16.1.2 Extruder operating characteristics

16.2 Equipment

16.2.1 Single-screw extruders

16.2.2 Twin-screw extruders

16.2.3 Control of extruders

16.3 Applications

16.3.1 Confectionery products

16.3.2 Cereal products

16.3.3 Protein-based foods

16.4 Effects on foods and micro-organisms

16.4.1 Sensory characteristics

16.4.2 Nutritional value

16.4.3 Effects on micro-organisms
References
Recommended further reading

Processing using hot oils

17 Frying

17.1 Theory

17.1.1 Heat and mass transfer

17.1.2 Frying time and temperature

17.1.3 Oil absorption

17.2 Equipment

17.2.1 Atmospheric fryers

17.2.2 Vacuum and pressure fryers

17.2.3 Control of fryer operation, oil filtration and heat recovery

17.3 Types of oils used for frying

17.4 Effects of frying on oils

17.5 Effects of frying on foods

17.6 Effects of frying on micro-organisms
References
Recommended further reading

Electromagnetic processing using direct and radiated energy

18 Dielectric, ohmic and infrared heating

18.1 Dielectric heating

18.1.1 Theory

18.1.2 Equipment

18.1.3 Applications

18.1.4 Effects on foods and micro-organisms

18.2 Ohmic Heating

18.2.1 Theory

18.2.2 Equipment and applications

18.2.3 Effects on foods and micro-organisms

18.3 Infrared heating

18.3.1 Theory

18.3.2 Equipment and applications

18.3.3 Effects on foods and micro-organisms
References
Recommended further reading

PART IV: PROCESSING BY REMOVAL OF HEAT

19 Heat removal by refrigeration

19.1 Theory

19.1.1 Refrigerants and cryogens

19.1.2 Magnetic refrigeration

19.1.3 The refrigeration cycle

19.2 Equipment

19.2.1 Control of mechanical refrigerators

19.2.2 Temperature monitoring
References
Recommended further reading

21 Chilling

21.1 Theory

21.2 Equipment

21.2.1 Mechanical chillers

21.2.2 Cryogenic chillers

21.2.3 Other methods of chilling

21.3 Applications to processed foods

21.3.1 Cook-chill systems

21.4 Effects on sensory and nutritional qualities of foods

21.5 Effects on micro-organisms
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

22.2.2 Cryogenic freezers

22.2.3 Developments in freezing technologies

22.3 Effects on foods

22.3.1 Freezing

22.3.2 Frozen storage

22.3.3 Thawing

22.4 Effects on micro-organisms
References
Recommended further reading

23 Freeze Drying and Freeze Concentration

23.1 Freeze drying

23.1.1 Theory

23.1.2 Equipment

23.1.3 Effects on foods and micro-organisms

23.2 Freeze concentration

23.2.1 Theory

23.2.2 Equipment

23.2.3 Effects on foods and micro-organisms
References
Recommended further reading

PART V POST-PROCESSING OPERATIONS

24 Packaging

24.1 Theory

24.1.1 Factors affecting the selection of a packaging material

24.1.2 Interactions between packaging and foods

24.2 Types of packaging materials

24.2.1 Textiles and wood

24.2.2 Metal

24.2.3 Glass

24.2.4 Flexible films

24.2.5 Paper and board

24.2.6 Combined packaging systems

24.3 Packaging materials for modified atmosphere packaging (MAP)

24.3.1 Effects on micro-organisms

24.4 Printing

24.4.1 Bar codes and other markings

24.5 Packaging developments

24.5.1 Edible and biodegradable packaging

24.5.2 Nanotechnology

24.5.3 Active and intelligent packaging

24.6 Environmental and regulatory considerations

24.6.1 Reductions in use of energy and materials

24.6.2 Re-use and recycling

24.6.3 Lifecycle analysis
References
Recommended further reading

25 Filling and sealing of containers

25.1 Rigid and semi-rigid containers

25.1.1 Filling

25.1.2 Sealing

25.2 Flexible containers

25.2.1 Form-fill-sealing

25.3 Twist-wrapping

25.4 Shrink-wrapping and stretch-wrapping

25.5 Tamper-evident packaging

25.6 Labelling

25.7 Checkweighing

25.8 Metal detection
References
Recommended further reading

26 Materials handling, storage and distribution

26.1 Materials handling

26.1.1 Solids handling methods

26.1.2 Liquid handling methods

26.2 Storage

26.2.1 Ambient storage

26.2.2 Temperature-controlled storage

26.2.3 Modified and controlled atmosphere storage

26.3 Logistics and control of storage and distribution
References
Recommended further reading

ANNEXES (on associated website)

Annex A. Food components
A1 Structure of food macromolecules
A1.1 Carbohydrates
A1.2 Lipids
A1.3 Amino acids and proteins
A2 Composition of foods
A2.1 Carbohydrates
A2.2 Lipids
A2.3 Proteins
A2.4 Water
A2.5 Vitamins
A2.6 Minerals
A2.7 Colourants and pigments
A2.8 Antioxidants
A2.9 Preservatives
A2.10 Natural toxicants
A3 Functional components of foods

Annex B Micro-organisms and enzymes
B1 Spoilage micro-organisms
B2 Pathogens
B2 Viruses
B3 Enzymes from GM micro-organisms
B4 Examples of food fermentations

Annex C. Quality assurance
C1 Food quality and shelf life
C1.1 Quality attributes
C1.2 Food safety
C1.3 Hurdle concepts
C1.4 Shelf life assessment
C1.5 Date marking
C1.6 Food authenticity and traceability
C2 Management of food quality and safety
C2.1 HACCP and prerequisite programmes
C2.2 Process monitoring and control
C2.3.1 Sensors
C2.3.2 Process analytical technology and quality by design
C2.3.3 Process controllers
C2.4 Neural networks and fuzzy logic
C3 Hygienic design and cleaning of processing facilities and equipment
C3.1 Hygienic design
C3.2 Cleaning and sanitation
C3.3 Water and waste management

Annex D. Glossary, acronyms, symbols
D1. Glossary
D2. List of acronyms
D3. Symbols

Annex E. Units and conversions