Infodoc : Sciences, Techniques et Culture

1 Chemistry of Milk - Role of Constituents in Evaporation and Drying
1.1 Introduction
1.2 Chemical components of liquid, concentrated and dried milk products
1.2.1 Protein
1.2.2 Fat
1.2.3 Carbohydrate
1.2.4 MineraIs
1.2.5 Water
1.2.6 Air
1.3 Surface composition of powders
1.4 Quality issues
1.4.1 Heat stability
1.4.2 Fouling
1.4.3 Age thickening
1.4.4 Maillard reactions
1.4.5 Oxidation

1 Chemistry of Milk - Role of Constituents in Evaporation and Drying
1.1 Introduction
1.2 Chemical components of liquid, concentrated and dried milk products
1.2.1 Protein
1.2.2 Fat
1.2.3 Carbohydrate
1.2.4 MineraIs
1.2.5 Water
1.2.6 Air
1.3 Surface composition of powders
1.4 Quality issues
1.4.1 Heat stability
1.4.2 Fouling
1.4.3 Age thickening
1.4.4 Maillard reactions
1.4.5 Oxidation
1.5 Conclusions
References
2 Current Legislation on Concentrated and Dried Milk Products
2.1 Introduction
2.2 European Union legislation
2.2.1 Access to EU legislation
2.2.2 Vertical-legislation on concentrated and dried milk products
2.2.3 Horizontal-hygiene and food safety requirements
2.2.4 Horizontal-food additives legislation
2.2.5 Horizontal-labelling requirements for foods
2.2.6 Horizontal-packaging legislation
2.3 United Kingdom legislation
2.3.1 Legislative basis
2.3.2 Background
2.3.3 Present legislation on composition
2.3.4 Present legislation on hygiene
2.3.5 The Dairy UK Code of Practice for HTST pasteurisation
2.4 Irish legislation
2.4.1 Introduction
2.4.2 Present legislation on hygiene
2.4.3 Present legislation on specific products
2.5 United States legislation
2.5.1 Introduction and background to US legislation
2.5.2 The 'Code of Federal Regulations'
2.5.3 Hygiene requirements for milk and certain milk products
2.5.4 US standards of identity and labelling
2.5.5 The USDA specifications and grading schemes for certain milk products
2.5.6 Food additives in US legislation
2.6 Legislation in Australia and New Zealand
2.6.1 Introduction
2.6.2 The 'Joint Food Standards Code'
2.6.3 New Zealand-specific legislation
2.7 The international perspective-Codex Alimentarius
2.7.1 What is Codex Alimentarius?
2.7.2 Codex Alimentarius Commission membership and structure
2.7.3 Codex Alimentarius standards
2.7.4 Codex Alimentarius-general standards
2.7.5 Codex Alimentarius standards for concentrated and dried milks
2.8 Private standards and specifications
2.9 Conclusions and possible future developments References
3 Technology of Evaporators, Membrane Processing and Dryers
3.1 Introduction
3.2 Evaporators
3.2.1 Principles of evaporation
3.2.2 Evaporation techniques and systems
3.2.3 Plant design of evaporator configuration
3.2.4 Heat economy in evaporator installation
3.2.5 Cleaning of evaporators
3.2.6 Evaporation versus membrane filtration
3.3 Membrane filtration technology
3.3.1 Principles of membrane filtration
3.3.2 Membrane filtration techniques and systems
3.3.3 Membrane filtration configurations
3.3.4 Heat economy in membrane filtration
3.3.5 Application of membrane filtration in the dairy industry
3.3.6 Cleaning of membrane filtration systems
3.4 Spray drying technology
3.4.1 Principles of spray drying
3.4.2 Spray drying techniques and systems
3.4.3 Plant design of spray drying configuration
3.4.4 Heat economy of spray drying
3.4.5 Cleaning of dryers
3.5 Conclusions References
4 Production of Evaporated Milk, Sweetened Condensed Milk and 'Dulce de Leche'
4.1 Background
4.2 Evaporated milk
4.2.1 Introduction
4.2.2 Evaporated milk production
4.2.3 Product properties
4.3 Sweetened condensed milk
4.3.1 Introduction
4.3.2 Production stages
4.4 'Dulce de leche'
4.4.1 Background
4.4.2 'Dulce de leche' production
4.4.3 Product properties
4.4.4 Rheological parameters
4.4.5 Results of a research on 'dulce de leche' using the UF process
4.5 Conclusions References
5 Dried Milk Products
5.1 Introduction
5.2 Definitions
5.2.1 Composition
5.2.2 Heat classification
5.2.3 Dispersion properties
5.3 Microbial quality
5.3.1 Raw milk
5.3.2 Effects of milk processing
5.4 Functionality and certain technical aspects
5.4.1 Heat treatment
5.4.2 Whey protein denaturation
5.4.3 Agglomeration and instantisation
5.5 Specific processes
5.5.1 Ordinary milk powders
5.5.2 Instant milk powders
5.5.3 Other types of milk powders
5.6 Quality assessment
5.6.1 Introduction
5.6.2 Milk
5.6.3 Concentrate
5.6.4 Powder
5.7 Conclusions
References
6 Casein and Related Products
6.1 Introduction
6.2 Products-definitions and structure
6.2.1 Acid casein
6.2.2 Caseinates
6.2.3 Phosphocasein
6.2.4 Rennet casein
6.2.5 Co-precipitate
6.2.6 Milk protein concentrates and isolates
6.2.7 Isolated and enriched casein fractions
6.2.8 Casein fragments
6.3 Methods of manufacture
6.3.1 Introduction
6.3.2 Acid casein-conventional treatment
6.3.3 Rennet casein
6.3.4 Caseinate
6.3.5 Co-precipitate
6.3.6 Acid casein-supercritical fluid processing
6.3.7 Fractionation of casein
6.3.8 Total milk protein
6.3.9 Casein-derived peptides
6.4 Functionality
6.4.1 Solubility
6.4.2 Heat and alcohol stability
6.4.3 Viscosity
6.4.4 Formation of protein-stabilised emulsions
6.4.5 Functionality of peptides derived from casein
6.5 Quality control References
7 Dried Whey, Whey Proteins, Lactose and Lactose Derivative Products
7.1 Introduction
7.2 Types and composition of raw whey and main whey-based powders
7.2.1 Standard and modified whey powders
7.2.2 Whey protein
7.2.3 Lactose and modified lactose products
7.2.4 Other whey-based powdered products
7.3 Unit operations in the production of concentrated and dried whey and whey-based products
7.4 Technological complexities in the production and storage of whey-based products
7.4.1 Heat sensitivity of whey protein
7.4.2 Low solubility and hygroscopicity of lactose
7.4.3 Content of lactic acid
7.4.4 Propensity for non-enzymatic Maillard browning reaction
7.4.5 Foam formation and its potential detrimental effects during drying
7.4.6 Free moisture in lactose powders
7.5 Modified whey-based products and their uses
7.6 Future trends
7.7 Sources of further information
References
8 Specialised and Novel Powders
8.1 Introduction
8.2 Principles
8.2.1 Moisture content
8.2.2 Carbohydrate content
8.2.3 High-fat content
8.2.4 Oxidation
8.2.5 Processing control
8.2.6 Particle solubility
8.3 Coffee whitener powders
8.3.1 Chemical composition
8.3.2 Manufacturing process
8.3.3 Functional properties
8.3.4 Recent developments
8.4 Novel whey products
8.4.1 Whey protein in nutraceutical applications
8.4.2 Heat-denatured whey protein
8.4.3 Cold gelling WPCs
8.4.4 Co-precipitation of whey protein with casein
8.5 Milk mineraI
8.6 Cheese powder
8.7 Hydrolysates
8.8 Cream powders
8.8.1 Why dried cream powders?
8.8.2 Emulsion stability
8.8.3 Processing of cream powders
8.8.4 Physicochemical properties of dairy cream powders
8.9 Concluding remarks
References
9 Infant Formulae - Powders and Liquids
9.1 Introduction
9.2 Historical background
9.3 Definition and classification of infant formula
9.4 An overview of the world market of infant formulae
9.4.1 Annual production figures
9.4.2 Worldwide manufacturers of infant formulae
9.5 Regulations governing infant formulae
9.5.1 General background
9.5.2 Cultural and religious aspects
9.5.3 Labelling
9.5.4 Procedures for placing infant food product on the market
9.6 Essential composition
9.6.1 Introduction
9.6.2 Proteins
9.6.3 Lipids
9.6.4 Carbohydrates
9.6.5 MineraIs
9.6.6 Vitamins
9.7 Food safety
9.7.1 Food additives
9.7.2 Hygiene and microbiological standards
9.8 Raw materials/ingredients
9.8.1 General aspects
9.8.2 Milk
9.8.3 Oils
9.8.4 Carbohydrates
9.9 Manufacture of dried infant formulae (powders)
9.9.1 Introduction
9.9.2 The 'wet mix' processing line
9.9.3 Preparation of the mix
9.9.4 Evaporation
9.9.5 Spray drying
9.9.6 Hygiene and production time between CIP cleaning
9.9.7 Structure of the powder
9.9.8 Drying parameters
9.9.9 Finished powder conveying system
9.9.10 Microbiological examination
9.10 Manufacture of liquid infant formulae (Ready-To-Feed and concentrates)
9.10.1 Dissolving of ingredients
9.10.2 First stage of standardisation
9.10.3 Oils and fat addition
9.10.4 First heat treatment and fat emulsification
9.10.5 Second stage of standardisation
9.10.6 Final conditioning
9.10.7 Retort sterilisation
9.10.8 UHT sterilisation and aseptic processing
9.10.9 Intermediate aseptic storage
9.10.10 Aseptic filling machines and packaging materials
9.10.11 Microbiological examination
9.11 Conclusion
References
10 Process Control in Evaporation and Drying
10.1 Background
10.2 Control technology
10.3 Measurement technology
10.4 Actuator technology
10.5 Communication technology
10.6 Control philosophies
10.7 Process dynamics
10.8 Evaporator control
10.8.1 Feed flow rate
10.8.2 Pre-heat temperature
10.8.3 Energy input
10.8.4 Condenser water flow rate
10.8.5 Level of total solids in the concentrate
10.8.6 Modelling approaches for evaporator control
10.8.7 Control of evaporator cleaning systems
10.9 Spray dryer control
10.9.1 Controlling the evaporative demand
10.9.2 Controlling the energy input
10.9.3 Controlling powder moisture content
10.9.4 Concentrate flow rate in disc atomising dryers
10.9.5 Concentrate flow rate in nozzle atomising dryers
10.9.6 Inlet air flow rate
10.9.7 Air-flow stability in spray dryers
10.9.8 Inlet air temperature
10.9.9 Chamber pressure
10.9.10 Outlet temperature in dryers without static fluid beds
10.9.11 Outlet temperature in spray dryeyers with integrated fluid geds
10.9.12 'Dummy' outlet temperature
10.9.13 Moisture control
10.9.14 A model-predictive approach to the control of a spray dryer
10.9.15 The influence of the protein content of the powder
10.9.16 Cleaning system control in spray drying
10.10 Conclusion References
11 Hazards in Drying
11.1 Background
11.2 Combustion
11.2.1 Smouldering combustion
11.2.2 Flaming combustion
11.2.3 Deflagrations
11.2.4 Detonations
11.2.5 Secondary explosions
11.3 Dust characteristics
11.3.1 Combustibility/explosibility
11.3.2 Upper and lower explosible limits
11.3.3 Minimum ignition temperature
11.3.4 Minimum ignition energy
11.3.5 Maximum explosion pressure and the rate of pressure rise
11.3.6 Particle size
11.3.7 Moisture content
11.4 Ignition sources
11.4.1 Flames
11.4.2 Hot surfaces
11.4.3 Mechanical friction
11.4.4 Impact sparks
11.4.5 Electrical sparks
11.4.6 Electrostatic discharge sparks
11.4.7 Hot work
11.4.8 Self-ignition
11.5 Hazards of dust explosions
11.6 Fire detection
11.6.1 Fast-acting temperature sensors
11.6.2 Infra-red optical detectors
11.6.3 Carbon monoxide detectors
11.6.4 Pressure sensors
11.6.5 Operator observation
11.7 Explosion suppression
11.7.1 Dry powder suppression
11.7.2 Chlorinated fluorocarbon compounds
11.7.3 Pressurised hot water
11.8 Explosion venting
11.8.1 Venting principles
11.8.2 Vent ducts
11.8.3 Vent doors and panels
11.9 Containment
11.10 Isolation
11.11 Inerting
11.12 Fire fightin
11.13 Conclusion
References