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Long recognized as the bestselling textbook for teaching food engineering to food science students, this 5e transitions with today’s students from traditional textbook learning to integrated presentation of the key concepts of food engineering. Using carefully selected examples, Singh and Heldman demonstrate the relationship of engineering to the chemistry, microbiology, nutrition and processing of foods in a uniquely practical blend. This approach facilitates comprehensive learning that has proven valuable beyond the classroom as a lifetime professional reference. New to this Edition: Communicates key concepts using audio, video, and animations Integrates interactive tools to aid in understanding complex charts and graphs Features multimedia guide to setting up Excel spreadsheets and working with formulae Demonstrates key processes and engineering in practice through videos Shows the relationship of engineering to the chemistry, microbiology, nutrition and processing of foods via carefully selected examples Presents a practical, unique and challenging blend of principles and applications for comprehensive learning Ideal for classroom use, valuable as a lifetime professional reference Front Cover......Page 1 Introduction to Food Engineering......Page 4 Copyright Page......Page 5 Contents......Page 6 About the Authors......Page 18 Foreword......Page 20 Preface......Page 22 1.1 Dimensions......Page 26 1.2.1 Base Units......Page 27 1.2.2 Derived Units......Page 28 1.2.3 Supplementary Units......Page 29 1.3 System......Page 35 1.4 State of a System......Page 36 1.4.1 Extensive Properties......Page 37 1.5 Density......Page 38 1.6 Concentration......Page 40 1.7 Moisture Content......Page 42 1.8 Temperature......Page 45 1.9 Pressure......Page 47 1.11 Equation of State and Perfect Gas Law......Page 51 1.12 Phase Diagram of Water......Page 52 1.13 Conservation of Mass......Page 54 1.13.1 Conservation of Mass for an Open System......Page 55 1.14 Material Balances......Page 57 1.15 Thermodynamics......Page 66 1.16.2 Second Law of Thermodynamics......Page 67 1.17 Energy......Page 68 1.19.1 Heat......Page 70 1.19.2 Work......Page 71 1.19.2.1 Work Due to a Moving Boundary......Page 72 1.19.2.3 Work Due to Change in Velocity......Page 74 1.19.2.4 Work Due to Shaft Rotation......Page 75 1.19.2.6 Energy Balance......Page 76 Heating at constant pressure involving phase change......Page 78 1.20 Energy Balance for an Open System......Page 80 1.21 A Total Energy Balance......Page 81 1.23 Area......Page 84 Problems......Page 85 List of Symbols......Page 88 Bibliography......Page 89 2 Fluid Flow in Food Processing......Page 90 2.1.1 Pipes for Processing Plants......Page 91 2.1.2.1 Centrifugal Pumps......Page 93 2.1.2.2 Positive Displacement Pumps......Page 96 2.2.1 Terminology Used in Material Response to Stress......Page 97 2.2.3 Viscosity......Page 98 2.3 Handling Systems for Newtonian Liquids......Page 106 2.3.1 The Continuity Equation......Page 107 2.3.2 Reynolds Number......Page 109 2.3.3 Entrance Region and Fully Developed Flow......Page 113 2.3.4 Velocity Profile in a Liquid Flowing Under Fully Developed Flow Conditions......Page 115 2.3.5 Forces Due to Friction......Page 121 2.4 Force Balance on a Fluid Element Flowing in a Pipe—Derivation of Bernoulli Equation......Page 125 2.5 Energy Equation for Steady Flow of Fluids......Page 132 2.5.2 Kinetic Energy......Page 136 2.5.4.1 Energy Loss Due to Sudden Contraction, Ef,contraction......Page 138 2.5.4.3 Energy Losses Due to Pipe Fittings......Page 139 2.5.5 Power Requirements of a Pump......Page 141 2.6.1 Centrifugal Pumps......Page 145 2.6.3 Pump Performance Characteristics......Page 147 2.6.4 Pump Characteristic Diagram......Page 151 2.6.5 Net Positive Suction Head......Page 152 2.6.6 Selecting a Pump for a Liquid Transport System......Page 156 2.6.7 Affinity Laws......Page 161 2.7 Flow Measurement......Page 162 2.7.1 The Pitot Tube......Page 166 2.7.2 The Orifice Meter......Page 168 2.7.4 Variable-Area Meters......Page 172 2.7.5 Other Measurement Methods......Page 173 2.8.1 Capillary Tube Viscometer......Page 174 2.8.2 Rotational Viscometer......Page 176 2.8.3 Influence of Temperature on Viscosity......Page 179 2.9.1 Properties of Non-Newtonian Fluids......Page 181 2.9.3 Volumetric Flow Rate of a Power Law Fluid......Page 188 2.9.5 Friction Factor and Generalized Reynolds Number for Power Law Fluids......Page 189 2.9.6 Computation of Pumping Requirement of Non-Newtonian Liquids......Page 192 2.10 Transport of Solid Foods......Page 195 2.10.1.1 Bulk Density......Page 196 2.10.1.2 Particle Density......Page 197 2.10.1.3 Particle Size and Size Distribution......Page 198 2.10.1.4 Particle Flow......Page 200 2.10.2 Flow of Granular Foods......Page 201 2.11 Process Controls in Food Processing......Page 204 2.11.1 Processing Variables and Performance Indicators......Page 206 2.11.3.1 Control Strategy......Page 208 2.11.3.2 Feed Backward Control System......Page 209 2.11.3.3 Feedforward Control System......Page 210 2.11.3.4 Stability and Modes of Control Functions......Page 211 2.11.3.5 On-Off Control......Page 212 2.11.3.6 Proportional Controller......Page 213 2.11.3.10 Final Control Element......Page 214 2.12.1 Temperature......Page 216 2.12.2 Liquid Level in a Tank......Page 218 2.12.3 Pressure Sensors......Page 219 2.12.4 Flow Sensors......Page 220 2.13 Dynamic Response Characteristics of Sensors......Page 221 Problems......Page 225 List of Symbols......Page 230 Bibliography......Page 232 3.1 Generation of Steam......Page 236 3.1.1 Steam Generation Systems......Page 237 3.1.2 Thermodynamics of Phase Change......Page 240 3.1.3 Steam Tables......Page 243 3.1.4 Steam Utilization......Page 249 3.2 Fuel Utilization......Page 253 3.2.1 Systems......Page 255 3.2.2 Mass and Energy Balance Analysis......Page 256 3.2.3 Burner Efficiencies......Page 258 3.3 Electric Power Utilization......Page 259 3.3.1 Electrical Terms and Units......Page 261 3.3.2 Ohm’s Law......Page 262 3.3.3 Electric Circuits......Page 263 3.3.4 Electric Motors......Page 265 3.3.5 Electrical Controls......Page 266 3.3.6 Electric Lighting......Page 267 3.4 Energy, Water and Environment......Page 269 3.4.1 Life Cycle Assessment......Page 270 3.4.2 Food System Applications......Page 274 Problems......Page 282 List of Symbols......Page 286 Bibliography......Page 287 4 Heat Transfer in Food Processing......Page 290 4.1.1 Plate Heat Exchanger......Page 291 4.1.2 Tubular Heat Exchanger......Page 295 4.1.3 Scraped-Surface Heat Exchanger......Page 296 4.1.4 Steam-Infusion Heat Exchanger......Page 298 4.1.5 Epilogue......Page 299 4.2.1 Specific Heat......Page 300 4.2.2 Thermal Conductivity......Page 303 4.2.3 Thermal Diffusivity......Page 305 4.3.1 Conductive Heat Transfer......Page 307 4.3.2 Convective Heat Transfer......Page 310 4.3.3 Radiation Heat Transfer......Page 312 4.4 Steady-State Heat Transfer......Page 313 4.4.1 Conductive Heat Transfer in a Rectangular Slab......Page 314 4.4.1.1 Thermal Resistance Concept......Page 315 4.4.2 Conductive Heat Transfer through a Tubular Pipe......Page 317 4.4.3.1 Composite Rectangular Wall (in Series)......Page 320 4.4.3.2 Composite Cylindrical Tube (in Series)......Page 323 4.4.4 Estimation of Convective Heat-Transfer Coefficient......Page 328 4.4.4.1 Forced Convection......Page 333 Turbulent flow in pipes......Page 334 Flow past immersed objects......Page 335 4.4.4.2 Free Convection......Page 340 4.4.4.3 Thermal Resistance in Convective Heat Transfer......Page 344 4.4.5 Estimation of Overall Heat-Transfer Coefficient......Page 345 4.4.6 Fouling of Heat Transfer Surfaces......Page 349 4.4.7 Design of a Tubular Heat Exchanger......Page 355 4.4.8.1 Heat Capacity Rate Ratio, C*......Page 363 4.4.8.2 Heat Exchanger Effectiveness, εE......Page 364 4.4.8.3 Number of Transfer Units, NTU......Page 365 4.4.9 Design of a Plate Heat Exchanger......Page 368 4.4.10 Importance of Surface Characteristics in Radiative Heat Transfer......Page 375 4.4.11 Radiative Heat Transfer between Two Objects......Page 377 4.5 Unsteady-State Heat Transfer......Page 380 4.5.1 Importance of External versus Internal Resistance to Heat Transfer......Page 382 4.5.2 Negligible Internal Resistance to Heat Transfer (NBi