1st Edition

Unit Operations in Food Engineering

    920 Pages 342 B/W Illustrations
    by CRC Press

    In order to successfully produce food products with maximum quality, each stage of processing must be well-designed. Unit Operations in Food Engineering systematically presents the basic information necessary to design food processes and the equipment needed to carry them out. It covers the most common food engineering unit operations in detail, including guidance for carrying out specific design calculations. Initial chapters present transport phenomena basics for momentum, mass, and energy transfer in different unit operations. Later chapters present detailed unit operation descriptions based on fluid transport and heat and mass transfer. Every chapter concludes with a series of solved problems as examples of applied theory.

    PREFACE
    ACKNOWLEDGEMENTS

    INTRODUCTION TO UNIT OPERATIONS: FUNDAMENTAL CONCEPTS
    Process
    Engineering of Food Processes
    Transformation and Commercialization of Agricultural Products
    Flow Charts: Description of Some Food Processes
    Steady and Unsteady States
    Batch, Continuous and Semicontinuous Operations
    Unit Operations: Classification
    Mathematical Set Up of Problems

    UNIT SYSTEMS: DIMENSIONAL ANALYSIS AND SIMILARITY
    Magnitude and Unit Systems
    Absolute Units
    Technical Unit Systems
    Engineering Unit Systems
    International Unit System (SI)
    Thermal Units
    Conversion of Units
    Dimensional Analysis
    Buckingham's Theorem
    Dimensional Analysis Methods
    Similarity Theory
    Geometric Similarity
    Mechanical Theory
    Problems

    INTRODUCTION TO TRANSPORT PHENOMENA
    Historic Introduction
    Transport Phenomena: Definition
    Circulation Regimes: Reynolds' Experiment
    Mechanisms of Transport Phenomena
    Mass Transfer
    Energy Transfer
    Momentum Transport
    Velocity Laws
    Coupled Phenomena

    MOLECULAR TRANSPORT OF MOMENTUM, ENERGY AND MASS
    Introduction
    Momentum Transport: Newton's Law of Viscosity
    Energy Transfer: Fourier's Law of Heat Conduction
    Mass Transfer: Fick's Law of Diffusion
    General Equation of Velocity

    AIR-WATER MIXTURES
    Introduction
    Properties of Humid Air
    Mollier's Psychrometric Chart for Humid Air
    Wet Bulb Temperature
    Adiabatic Saturation of Air
    Problems

    RHEOLOGY OF FOOD PRODUCTS
    Introduction
    Stress and Strain
    Elastic Solids and Newtonian Fluids
    Viscometric Functions
    Rheological Classification of Fluid Foods
    Newtonian Flow
    Non-Newtonian Flow
    Viscoelasticity
    Effect of Temperature
    Effect of the Concentration on the Viscosity
    Mechanical Models
    Rheological Measurements in Semiliquid Foods
    Problems

    TRANSPORT OF FLUIDS THROUGH PIPES
    Introduction
    Circulation of Incompressible Fluids
    Macroscopic Balance in the Circulation of Fluids
    Mechanical Energy Losses
    Friction Factors
    Design of Piping
    Pumps
    Problems

    CIRCULATION OF FLUID THROUGH POROUS BEDS: FLUIDIZATION
    Introduction
    Darcy's Law: Permeability
    Previous Definitions
    Equations of Flow through Porous Beds
    Fluidization
    Problems

    FILTRATION
    Introduction
    Filtration Fundamentals
    Filtration at Constant Pressure Drop
    Filtration at Constant Volumetric Rate
    Cake Washing
    Filtration Capacity
    Optimus Filtration Conditions at Constant Pressure
    Rotary-Drum Vacuum Filters
    Problems

    SEPARATION PROCESSES BY MEMBRANES Introduction
    Models of Transfer through the Membrane
    Models of Transfer through the Polarization Layer
    Inverse Osmosis
    Ultrafiltration
    Design of Inverse Osmosis and Ultrafiltration Systems
    Operative Layout of the Modules
    Problems

    THERMAL PROPERTIES OF FOODS
    Thermal Conductivity
    Specific Heat
    Density
    Thermal Diffusivity
    Problems

    HEAT TRANSFER BY CONDUCTION
    Fundamental Equations of Heat Conduction
    Steady-State Heat Conduction
    Unsteady-State Heat Conduction
    Problems

    HEAT TRANSFER BY CONVECTION
    Introduction
    Heat Transfer Coefficients
    Concentric Tube Heat Exchangers
    Shell and Tube Heat Exchangers
    Plate-Type Heat Exchangers
    Extended-Surface Heat Exchangers
    Scraped-Surface Heat Exchangers
    Agitated Vessels with Jacket and Coils
    Heat Exchange Efficiency
    Problems

    HEAT TRANSFER BY RADIATION
    Introduction
    Fundamental Laws
    Properties of Radiation
    Vision factors
    Interchange of Radiation Energy between Surfaces Separated by Non-Absorbent Media
    Coefficient of heat transfer by radiation
    Simultaneous heat transfer by convection and radiation
    Problems

    THERMAL PROCESSING OF FOODS
    Introduction
    Kinetics of Thermal Destruction
    Treatment of Packed Products
    Thermal Treatment in the Aseptic Processing
    Problems

    FOOD PRESERVATION BY COOLING
    Freezing
    Freezing Temperature
    Thermal Properties of Frozen Foods
    Freezing Time
    Design of Freezing Systems
    Refrigeration
    Refrigeration Mechanical Systems
    Refrigerants
    Multipressure Systems
    Problems

    DEHYDRATION
    Introduction
    Mixture of Two Air Streams
    Material and Heat Balances in Idealized Dryers
    Dehydration Mechanisms
    Chamber and Bed Dryers
    Spray Drying
    Freeze-Drying
    Other Types of Drying
    Problems

    EVAPORATION
    Introduction
    Heat Transfer in Evaporators
    Single-Effect Evaporators
    Use of Released Vapor
    Multiple-Effect Evaporators
    Evaporation Equipment
    Problems

    DISTILLATION
    Introduction
    Liquid-Vapor Equilibrium
    Distillation of Binary Mixtures
    Continuous Rectification of Binary Mixtures
    Discontinuous Rectification
    Steam Distillation
    Problems

    ABSORPTION
    Introduction
    Liquid-Gas Equilibrium
    Absorption Mechanisms
    Packed Columns
    Plate Columns
    Problems

    SOLID-LIQUID EXTRACTION
    Introduction
    Solid-Liquid Equilibrium
    Extraction Methods
    Solid-Liquid Extraction Equipment
    Applications to the Food Industry
    Problems

    ADSORPTION AND IONIC EXCHANGE
    Introduction
    Equilibrium Processes
    Process Kinetics
    Operation by Stages
    Movable Bed Columns
    Fixed Bed Columns
    Problems
    REFERENCES
    APPENDIX
    INDEX

    Biography

    Albert Ibarz, Gustavo V. Barbosa-Canovas