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Preface1 An introduction to food process engineering2 Dimensions, quantities and units2.1 Dimensions and units2.2 Definitions of some basic physical quantities2.2.1 Velocity and speed2.2.2 Acceleration2.2.3 Force and momentum2.2.4 Weight2.2.5 Pressure2.2.6 Work and energy2.2.7 Power2.3 Dimensional analysis2.3.1 Dimensional consistency2.3.2 Dimensional analysis3 Thermodynamics and equilibrium3.1 Introduction3.1.1 Temperature and the zeroth law of thermodynamics3.1.2 Temperature scale3.1.3 Heat, work and enthalpy3.1.4 Other definitions3.2 The gaseous phase3.2.1 Kinetic theory of gases3.2.2 Perfect gases3.2.3 Pure component vapour pressure3.2.4 Partial pressure and pure component volume3.3 The liquid-vapour transition3.3.1 Vaporisation and condensation3.3.2 Isotherms and critical temperature3.3.3 Definition of gas and vapour3.3.4 Vapour-liquid equilibrium3.4 First law of thermodynamics3.5 Heat capacity3.5.1 Heat capacity at constant volume3.5.2 Heat capacity at constant pressure3.5.3 The relationship between heat capacities for a perfect gas3.5.4 The pressure, volume, temperature relationship for gases3.6 Second law of thermodynamics3.6.1 The heat pump and refrigeration3.6.2 Consequences of the second law4 Material and energy balances4.1 Process analysis4.2 Material balances4.2.1 Overall material balances4.2.2 Concentration and composition4.2.3 Component material balances4.2.4 Recycle and by-pass4.3 The steady-flow energy equation4.4 Thermochemical data4.4.1 Heat capacity4.4.2 Latent heat of vaporisation4.4.3 Latent heat of fusion4.4.4 Steam tables4.5 Energy balances5 The fundamentals of rate processes5.1 Introduction5.2 Heat transfer5.3 Momentum transfer5.4 Mass transfer5.5 Transport properties5.5.1 Thermal conductivity5.5.2 Viscosity5.5.3 Diffusivity5.6 Similarities between heat, momentum and mass transfer6 The flow of food fluids6.1 Introduction6.2 Fundamental principles6.2.1 Velocity and flow rate6.2.2 Reynolds'' experiment6.2.3 Principle of continuity6.2.4 Conservation of energy6.3 Laminar flow in a pipeline6.4 Turbulent flow in a pipeline6.5 Pressure measurement and fluid metering6.5.1 The manometer6.5.2 The orifice meter6.5.3 The venturi meter6.6. Pumping of liquids6.6.1 The centrifugal pump6.6.2 Positive displacement pumps6.6.3 Net positive suction head6.6.4 Hygienic design6.7 Non-Newtonian flow6.7.1 Introduction6.7.2 Stress, strain and flow6.8 Time-independent rheological models6.8.1 Hookean solids6.8.2 Newtonian fluids6.8.3 Bingham fluids6.8.4 The power law6.8.5 Laminar flow of power law fluids6.8.6 Other time-independent models6.9 Time-dependent rheological models6.10 Visco-elasticity6.10.1 Introduction6.10.2 Mechanical analogues6.11 Rheological measurements6.11.1 Measurement of dynamic viscosity6.11.2 Rheological measurements for non-Newtonian fluids7 Heat processing of foods7.1 Introduction7.2 Conduction7.2.1 Steady-state conduction in a uniform slab7.2.2 Conduction in a composite slab7.2.3 Radial conduction7.2.4 Conduction in a composite cylinder7.2.5 Conduction through a spherical shell7.3 Convection7.3.1 Film heat transfer coefficient7.3.2 Simultaneous convection and conduction7.3.3 Radial convection7.3.4 Critical thickness of insulation7.3.5 Correlations for film heat transfer coefficients7.3.6 Overall heat transfer coefficient7.4 Heat exchangers7.4.1 Types of industrial heat exchanger7.4.2 Sizing of heat exchangers7.5 Boiling and condensation7.5.1 Boiling heat transfer7.5.2 Condensation7.6 Heat transfer to non-Newtonian fluids7.7 Principles of radiation7.7.1 Absorption, reflection and transmission7.7.2 Black body radiation7.7.3 Emissivity and real surfaces7.7.4 Radiative heat transfer7.7.5 View factors7.8 Microwave heating of foods7.8.1 Microwaves7.8.2 Generation of microwaves7.8.3 Energy conversion and heating rate7.8.4 Microwave ovens and industrial plant7.8.5 Advantages and applications of microwave heating7.9 Temperature measurement7.9.1 Principles of temperature measurement7.9.1 Expansion thermometers7.9.3 Electrical methods7.9.4 Radiation pyrometry8 Mass Transfer8.1 Introduction8.2 Molecular diffusion8.2.1 Fick''s law8.2.2 Diffusivity8.2.3 Concentration8.3 Convective mass transfer8.3.1 Whitman''s theory8.3.2 Film mass transfer coefficients8.3.3 Overall mass transfer coefficients8.3.4 Addition of film mass transfer coefficients8.3.5 Resistances to mass transfer in food processing8.3.6 Effect of solubility on mass transfer coefficients8.3.7 Alternative units for mass transfer coefficients8.3.8 Units of Henry''s constant8.4 Binary diffusion8.4.1 General diffusion equation8.4.2 Other forms of the general diffusion equation8.4.3 Diffusion through a stagnant gas film8.4.4 Particles, droplets and bubbles8.5 Correlations for mass transfer coefficients8.6 Mass transfer and food packaging9 Psychrometry9.1 Introduction9.2 Definitions of some basic quantities9.2.1 Absolute humidity9.2.2 Saturated humidity9.2.3 Percentage saturation9.2.4 Relative humidity9.2.5 Relationship between percentage saturation and relative humidity9.2.6 Humid heat9.2.7 Humid volume9.2.8 Dew point9.3 Wet bulb and dry bulb temperatures9.3.1 Definitions9.3.2 The wet bulb equation9.3.3 Adiabatic saturation temperature9.3.4 Relationship between wet bulb temperature and adiabatic saturation temperature9.4 The psychrometric chart9.4.1 Principles9.4.2 Mixing of humid air streams9.5 Application of psychrometry to drying10 Thermal processing of foods10.1 Unsteady-state heat transfer10.1.1 Introduction10.1.2 The Biot number10.1.3 Lumped analysis10.2 Unsteady-state conduction10.2.1 Fourier''s first law of conduction10.2.2 Conduction in a flat plate10.2.3 The Fourier number10.2.4 Gurney-Lurie charts10.2.5 Heisler charts10.3 Food preservation techniques using heat10.3.1 Introduction to thermal processing10.3.2 Pasteurisation10.3.3 Commercial sterilisation10.4 Kinetics of microbial death10.4.1 Decimal reduction time and thermal resistance constant10.4.2 Process lethality10.4.3 Spoilage probability10.5 The general method10.6 The mathematical method10.6.1 Introduction10.6.2 The procedure to find total process time10.6.3 Heat transfer in thermal processing10.6.4 Integrated value10.7 Retorts for thermal processing10.7.1 The batch retort10.7.2 Design variations10.7.3 Continuous retorts10.8 Continuous flow sterilisation10.8.1 Principles of UHT processing10.8.2 Process description11 Low temperature preservation11.1 Principles of low temperature preservation11.2 Freezing rate and freezing point11.3 The frozen state11.3.1 Physical properties of frozen food11.3.2 Food quality during frozen storage11.4 Freezing equipment11.4.1 Plate freezer11.4.2 Blast freezer11.4.3 Fluidised bed freezer11.4.4 Scraped surface freezer11.4.5 Cryogenic and immersion freezing11.5 Prediction of freezing time11.5.1 Plank''s equation11.5.2 Nagaoka''s equation11.5.3 Stefan''s model11.5.4 Plank''s equation for brick-shaped objects11.6 Thawing11.7 Principles of vapour compression refrigeration11.7.1 Introduction11.7.2 The refrigerant11.7.3 The evaporator11.7.4 The compressor11.7.5 The condenser11.7.6 The valve or nozzle11.7.7 The refrigeration cycle12 Evaporation and drying12.1 Introduction to evaporation12.2 Equipment for evaporation12.2.1 Natural circulation evaporators12.2.2 Forced circulation evaporators12.2.3 Thin film evaporators12.3 Sizing of a single effect evaporator12.3.1 Material and energy balances12.3.2 Evaporator efficiency12.3.3 Boiling point elevation12.4 Methods of improving evaporator efficiency12.4.1 Vapour recompression12.4.2 Multiple effect evaporation12.4.3 An example of multiple effect evaporation: the concentration of tomato juice12.5 Sizing of multiple effect evaporators12.6 Drying12.6.1 Introduction12.6.2 Water activity12.6.3 Effect of water activity on microbial growth12.6.4 Moisture content12.6.5 Isotherms and equilibrium12.7 Batch drying12.7.1 Rate of drying12.7.2 Batch drying time12.8 Types of drier12.8.1 Batch and continuous operation12.8.2 Direct and indirect driers12.8.3 Cross-circulation and through-circulation12.8.4 Tray drier12.8.5 Tunnel drier12.8.6 Rotary drier12.8.7 Fluidised bed drier12.8.8 Drum drier12.8.9 Spray drier12.9 Freeze drying12.9.1 Stages in the freeze drying process12.9.2 Prediction of freeze-drying time13 Solids processing and particle manufacture13.1 Characterisation of particulate solids13.1.1 Particle size distribution13.1.2 Mean particle size13.1.3 Particle shape13.1.4 Methods of determining particle size13.1.5 Mass distributions13.1.6 Other particle characteristics13.2 The motion of a particle in a fluid13.2.1 Terminal falling velocity13.2.2 Particle drag coefficient13.2.3 Effect of increasing Reynolds number13.3 Packed beds: the behaviour of particles in bulk13.4 Fluidisation13.4.1 Introduction13.4.2 Minimum fluidising velocity in aggregative fluidisation13.4.3 Gas-solid fluidised bed behaviour13.4.4 Bubbles and particle mixing13.4.5 Heat and mass transfer in fluidisation13.4.6 Applications of fluidisation to food processing13.4.7 Spouted beds13.4.8 Particulate fluidisation13.5 Two-phase flow: pneumatic conveying13.5.1 Introduction13.5.2 Mechanisms of particle movement13.5.3 Pneumatic conveying regimes13.5.4 Pneumatic conveying systems13.5.5 Safety issues13.6 Food particle manufacturing processes13.6.1 Classification of particle manufacturing processes13.6.2 Particle-particle bonding13.6.3 Fluidised bed granulation13.6.4 Other particle agglomeration methods13.7 Size reduction13.7.1 Mechanisms and material structure13.7.2 Size reduction equipment13.7.3 Operating methods13.7.4 Energy requirement for size reduction14 Mixing and separation14.1 Mixing14.1.1 Definitions and scope14.1.2 Mixedness14.1.3 Mixing index and mixing time14.1.4 Mixing of liquids14.1.5 Power consumption in liquid mixing14.1.6 Correlations for the density and viscosity of mixtures14.1.7 Mixing of solids14.1.8 Equipment for solids mixing14.2 Filtration14.2.1 Introduction14.2.2 Analysis of cake filtration14.2.3 Constant pressure filtration14.2.4 Filtrati