Food Process Engineering and Technology
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- Điều hướng trang này:
- Thermal conductivity (w.m 1
- Table A.16 Continued Temperature ( ⴗC)
- 1000 (39.3) h s h s h s h
- Figure A.2
- Figure A.3
- Figure A.6
- Figure A.7
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Appendix Table A.17 Properties of air at atmospheric pressure Temperature ( ⴗ C) Density (kg.m 3 ) Viscosity (Pa.s) Thermal conductivity (w.m 1 .K 1 ) Specifi c heat ( J.kg 1 .K 1 ) Prandl number (9 dimensionless) 0
1.25 17.5 10 6
0.0238
1010 0.74
20 1.16
18.2 10 6
1012 0.73
40 1.09
19.1 10 6
1014 0.73
60 1.03
20.0 10 6
1017 0.72
80 0/97
20.8 10 6
1019 0.72
100 0.92
21.7 10 6
1022 0.72
120 0.87
22.6 10 6
1025 0.72
140 0.83
23.3 10 6
1027 0.72
160 0.79
24.1 10 6
1030 0.72
180 0.75
24.9 10 6
1032 0.72
200 0.72
25.7 10 6 0.0370
1035 0.72
Table A.16 Continued Temperature ( ⴗC) Pressure (kPa); (Saturation temperature ⴗC) 50 ( ⴚ40) 100 ( ⴚ26) 200 ( ⴚ 10) 400 (9) 600 (21.5) 1000 (39.3) h s h s h s h s h s h s 65
461 2.072
460 2.014
459 1.954
456 1.892
453 1.853
447 1.972
70 465
2.085 465
2.027 463
1.968 461
1.906 458
1.867 452
1.813 75
470 2.098
493 2.040
468 1.981
466 1.920
663 1.881
457 1.828
80 475
2.111 474
2.054 473
19995 470 1.934
468 1.895
463 1.842
h enthalpy; s entropy. Note: This is an abridged summary table. For more detailed data please consult: http://refrigerants.dupont.com or http://eng.sdsu.edu/testcenter/testheme
Appendix 587 0 0.01 0.02 0.03
0.04 0.05
0.06 0.07
1.00E 03
1.00E 04
1.00E 05
1.00E 06
Reynolds number Friction factor Transition zone Smooth pipe ε/D 0.001 ε/D 0.0001 Turbulent zone Laminar zone Figure A.1 Friction factors for fl ow in pipes 0 0.01
0.02 0.03
0.04 0.05
0.06 0.07
0.08 0.09
0.1 10 20 30 40 50 60 70 80 90 Dry bulb temperature, C H, kg water vapor/kg dry air 100%
80% 60%
40% 20%
10% 5% 50 40 30 20 Wet-bulb temperature, C Figure A.2 Psychrometric chart
588 Appendix 0.1
10 1 100 1 10 100 1000 10 000
100 000 Reynolds number Power function φ Baffled Unbaffled Figure A.4 Mixing power function, propeller impellers 1 10
1 10 100 1000 10 000
100 000 Reynolds number Power function φ Baffled Unbaffled Figure A.3 Mixing power function, turbine impellers Appendix 589 0 0.001 0.01 0.1
1 0.5
1 1.5
2 2.5
N Bi ∞ N Bi 2 N Bi 1 N Bi 0.5 αt/L 2 3 3.5 4 4.5 5 Θ
Unsteady state heat transfer in a slab 0 0.001 0.01 0.1
1 0.5
1 1.5
2 2.5
N Bi ∞ N Bi 2 N Bi 1 N Bi 0.5 αt/R 2 3 3.5 Θ
Unsteady state heat transfer in an infi nite cylinder
590 Appendix 0 0.001 0.01 0.1
1 0.1
0.2 0.3
0.4 0.5
Dt/z 2 0.6 0.7 E Sphere Infinite cylinder Infinite slab E
C ∞ C C ∞ C 0 Figure A.8 Unsteady state mass transfer, average concentration 0 0.001
0.01 0.1
1 0.5
1 1.5
2 2.5
N Bi ∞ N Bi 2 N Bi 1 N Bi 0.5 αt/R 2 3 3.5 Θ
Unsteady state heat transfer in a sphere
Appendix 591 0 0.1 0.2 0.3
0.4 0.5
0.6 0.7
0.8 0.9
1 0 0.5 1 1.5
2 2.5
X erf(X)
Figure A.9 Error
function Food Process Engineering and Technology Copyright © 2009, Elsevier Inc. ISBN: 978-0-12-373660-4 All rights reserved Index Absorption cycle 417–8 Absorptivity 96 Activation energy 120 Actuator 130 Adiabatic saturation 462–3 Adsorption 279–94 batch 282–7 column 287–8 repeated batch 284 Agglomeration 504 Angle of repose 61 Appert, Nicolas 355 Arrhenius equation 119–20 , 392 Aseptic processing 388–90 Asymmetric membranes 246 Atomizing 153 Autoclave see Retort Azeotrope 296 Baking 528–30 impingement oven 530 microwave 530 ovens 529–30 Barometric leg 447, 448 Beer-Lambert law 535 Belt dryer 489 Belt-trough dryer 489 Bernoulli equation 43–6 BET (Brunau. Emmett, Teller) model 18 , 281 BET monolayer 18 , 281 Bimetal thermometers 143 Bin dryer 490–1 Bingham fl uids 40 Biofi lms 563 Biot number 91 Black body 96 Blanching 356 Block diagram (control) 132–3 Boiling point elevation (BPE) 431 , 436 Boiling point 436–7 Boundary layer (in turbulent fl ow) 36–7 Bourdon gage 145 Breakthrough curve 288 Brix (ºBrix), Bx 432 Cabinet dryer 486–7 Cakes (fi ltration) 205–6 Calandria 438 , 451 Can seamers 379–80 Canning 375 Capillary viscosimeter 32–3 Cellophane 551 Centrifugation 217–32 Centrifuges 227–30 basket 230 decanter 230 desludger (self cleaning) 229 nozzle 228 solid-wall bowl 228 tubular 227 Characteristic curve 46 Chemical reactions 115–6 elementary 116 non-elementary 116 Chilling 391–400 Chlorine 567–8
594 Index Chopping 153 , 171 Cleaning in place (CIP) 570 Cleaning out of place (COP) 570 Cleaning 561–92 dry 569–70 effect of cleaning agent 564–6 effect of contaminant 562–4 effect of shear 566 effect of support 564 effect of temperature 566 kinetics 562–6 wet 568–9 Climacteric crops 398 Coeffi cient of performance (COP) 415 Cognac, distillation of 315 Cold chain 391 , 423 Cold storage 420–3 Collection effi ciency 197 Combined processes 353 Compression ratio (extruder) 336 Concentration polarization 238–9 Condensers (evaporation) 447 direct ( jet) 447, 448 indirect 447, 448 Conductive switch 147 Conductometry 148 Control loop 130–1 Control modes 136–141 integral 139–40 on-off 136–7 proportional 138–9 proportional-integral (PI) 140 proportional-integral-differential 140 Control valve 149–50 normally closed 149 normally open 149–50 Controlled atmosphere (CA) 398–9 Controller 130 intelligent controller 149 programmable logic controller (PLC) 149 Corrosion, tinplate 555–6 Coulomb’s law of friction 58–9 Critical moisture content 467 Crystal growth 320–3 Crystallization 317–31 kinetics 318–23 salt 327–8 sucrose 325–7 Crystallizers (pans) 323 Cutters 171–4 bowl 171–2 cube 171 silent 171 water jet 173–4 Cutting 153 , 171–4 Cyclone 231–2 Darcy’s law 200 , 235 Decimal reduction time 356–8 effect of temperature 358–60 Deformation 8–9 elastic 8 plastic 8–9 Dehydration (drying) 459–510 conductive 460 , 481–5 convective 460 , 464–81 drum 483 effect on quality 460 , 502–3 energy consumption 505–7 fi xed bed 480–1 kinetics 460 objectives of 459 radiation 477 sun (solar) 501 superheated steam 484–5 tray 478–80 tunnel or belt 481 vacuum 484 Desorption drying 512 Dew point 463 Dielectric loss factor 108 Dielectric loss tangent 108 Dielectric permittivity 108 Differential scanning calorimetry (DSC) 23 Diffusivity 73–6 effective 75 Dilatant fl uids 40 Disc-bowl centrifuge capacity 223–4 Disinfection 561–92 kinetics 567–8 Dissolution 328–30 Distillation 295–315 batch (differential) 301 bottoms 295 continuous fl ash 298 Index 595 distillate 295 fractional 304–313 residue 295 steam 313 Dittus-Boelter correlation 85 Double seam 379–80 Drum dryer 499–500 classifi cation 499 feeding methods 500 Drying curve 464–7 characteristic 477–8 constant rate 466 , 467–70 falling rate 466 , 470–2 rising rate 466 Drying rate 464–5 effect of external conditions 475–6 Drying time 472–5 Ejector 55 Electrical conductivity 111 Electrical properties 11 Electrodialysis 253–4 Electromagnetic waves ( γ rays) 533 , 535–7 Electron accelerators 534–5 Electron beams ( β rays) 533 , 535–6 Electrostatic forces 57 End-over-end agitation 366 Energy balance 3 Ergun equation 63–4 Error (deviation) 130 Error function 95 Ethylene 398 Evaporation 429–58 aroma loss and recovery 457 cut-back 457–8 energy balance 430–2 energy economy 440–7 material balance 430–2 objectives of 429 thermal damage to quality 454 Evaporators 448–53 centrifugal 453 climbing fi lm 451–2 falling fi lm 453 forced circulation 439 natural circulation 451 open pan 448 plate 453 Robert 450 swept surface 453 vacuum pan 449 EVOH 551 Exhausting, thermal 378 Expression 211–5 applications 213–5 mechanism 211–3 Extinction coeffi cients 536 Extraction 259–77 equilibrium 260 , 262 kinetics 260 material balance 260 , 262 multistage countercurrent 262–7 stage effi ciency 266 supercritical 271–6 Extractors 268–71 auger 271 basket 271 carousel 270–1 fi xed bed 268–9 moving belt 269–70 Extruder barrel 334 Extruder die 335 Extruder screw 335 Extruder, single screw 334–40 Extruder, twin-screw 340–343 co-rotating 341 counter-rotating 341 Extrusion cooking 333–4 Extrusion 333–50 breakfast cereals 346–7 chocolate 349 confectionery 348–9 effect on foods 343–5 effect on proteins 344–5 effect on starch 344 expanded snacks 345–6 fl ow models 337–40 forming (pasta) 345 pellets 347 pet foods 349 residence time 340 F value 361 F 0
Feather’s rule 535 Fick’s 2nd law 89–92 596 Index Fick’s 1st law 70–3 Filled thermometers 142 Filler 375–7 hand 376 hand-pack 376 piston 377 tumbler 377 Filling, hot 378 Film boiling 435 Film, steady state mass transfer 79–80 Filter aid 206 Filters 207–10 cartridge 208 depth 207 fi lter centrifuge 210 fi lter press 208 frame-and-plate 208 rotary vacuum 208–10 Filtration 195–216 constant pressure 201–4 constant rate 201–4 cross-fl ow see tangential fi ltration dead-end 199 depth 196–8 optimization 204–5 surface (barrier) 198–206 Finite shapes, transient conduction 92–4 Float switch 147 Flow diagram (process) 4–6 block 4 engineering 5–6 equipment 4 Flow Function (ffc) 61 Flow through porous media 199 Fluid dynamics 27 Fluid fl ow 27–67 Fluid head 38 Fluidization point 62–4 Fluidization 62–5 Fluidized bed dryer 497–8 Fluidized bed 62–5 Food chemistry 7 Food physics 7 Food processes 1–6 batch 3 continuous 4 mixed 4 preservation 1 transformation 1 Food safety 3 Fouling 104–5 Fourier transform infrared spectroscopy (FTIR) 148 Fourier’s 1st law 70–3 Fourier’s 2nd law 89–92 Freeze concentration 520–2 basic principles 520 process 521–2 Freeze dryers 519–20 batch 520 continuous 520 structure 519–20 Freeze drying 511–23 advantages 511 commercial facilities 518–9 in practice 518–9 kinetics 512–8 Freezers 423–6 blast 423–5 cabinet 423 fl uidized bed 424–5 plate 425–6 scraped surface 426 spiral belt 424 tunnel 424 Freezing 400–28 cryogenic 426–7 effect on texture 408–9 point 401–2 time 402–8 Freundlich’s model 281 Friction factor chart 37–8 Friction factor 37 Froude number (Fr) 178–9 Frozen storage 409–10 effect on food quality 409–10 Frying 525–8 deep (immersion) 526 heat and mass transfer 526–7 pan 525–6 stir 526 systems 527–8 Fuzzy logics 149 Gel polarization 239–40 Glass transition temperature 20–3 Glassy state 19–20 Grain dryer 492 Index 597 Grashof Number 82 Gray (radiation dose unit) 537 Grinding 153 Guggenheim-Anderson-de Boer (GAP) model 19 Hagen-Poiseuille equation 31 Half life 119 Head space 376 , 378 Heat exchangers 100–107 plate 106–7 scraped surface 107 shell-and-tube 106 tubular 105–6 Heat transfer coeffi cient 81–7 Heat transfer in evaporation 432–40 overall coeffi cient 433–6 temperature drop 436–40 Heat transfer 69–112 conduction 70–81 convection 81–7 radiation 96–100 Heating lag factor, j 367 Helicoidal extractor 214 Herschel-Bulkley fl uids 40 High pressure preservation 541 High temperature–short time (HTST) 363 Homogenization 153 , 189–93 mechanism 189–91 Homogenizers 191–2 high pressure 191–2 high shear 191 ultrasonic 192 Hot-wire anemometer 147 Humidity 461 absolute 461 relative 462 Hurdle effect see Combined processes Hydraulic diameter 29 Hydraulic permeability 236 Hysteresis 17 Individual quick freezing (IQF) 424–5 Infrared thermometry 144 Interphase mass transfer 87–8 Ion exchange 286–94 Ion exchangers 289–92 cross-linkage 291 electrolytic properties 291 exchange capacity 289 selectivity 290–1 Ionizing irradiation 533–41 biological effects 538–9 chemical effects 538 industrial applications 540–1 Isotope sources 534 Jenike shear cell 59–60 Joule’s law 110 Juice extractor (citrus) 215 Kick’s law 165 Kneading 181–2 Kozeny-Carman equation 64 , 205–6 Laminar fl ow 28–36 around immersed particless 34–6 in tube 30–3 on fl at surfaces 33–4 Langmuir’s model of adsorption 280–1 Lethality 360 Liquid bridge 57 Liquid carbon dioxide 427 Liquid nitrogen 427 Liquid-liquid extraction 259 , 276–7 Liquid-liquid separation (centrifugal) 224–6 Low temperature 392–400 effect on chemical spoilage 392–5 effect on enzymes 395–6 effect on microorganisms 396–7 effect on physical properties 399–400 effect on respiring tissues 396–9 MacLeod Gage 144 Manometers 144 Mashing 153 Mass fl owmeter (Coriolis) 147 Mass transfer coeffi cient 81–7 Mass transfer 69–112 Massecuite 325 Material balance 3 Mean temperature difference, logarithmic 103 Mechanical properties 8–9 Membrane confi gurations 247–9 hollow fi ber 249 plate-and-frame 247 spiral wound 247 tubular 248
598 Index Membrane processes 233–57 Membrane systems 245–9 Mesophiles 396–7 Michaelis-Menten constant 121 Michaelis-Menten equation 121 Microbial growth 122 decline phase 122 lag phase 122 log phase 122 stationary phase 122 Microfi ltration (MF) 233 , 249 Microwaves 107–9 Mills 166–70 attrition 168–70 ball 169 colloid 170 disc 168–9 hammer 166–7 impact 166 pressure 167 roller 167 Mixer dryer 501 Mixers 175–89 anchor 175 drum 187 paddle 175 planetary 182 propeller 176 ribbon 189 sigma blade 182–3 tumbler 188 turbine 175 V-shaped 188 Mixing 175–93 energy input 178 fl ow patterns 177 fl uids (blending) 175–84 quality (mixedness) 184–6 solids 184–9 Mohr diagram 60 Molasses 326 Molecular mobility 391 Montreal Protocol 419 Mother liquor 317 , 321 Multilayer slab 76 Multiple effect evaporation 441–5 feed backward 442 feed-forward 441 optimization 443–4 Murphee effi ciency 266 Nanofi ltration (NF) 233 Net suction pressure 46 Neural network 149 Newman’s law 94 Newtonian fl uids 28 , 40 Non-Newtonian fl uids 28 fl ow in pipe 41–2 Nucleate boiling 435 Nucleation 318–20 heterogeneous 319 homogeneous 319 secondary 320 Nusselt Number 82 Odor abatement 571–2 biofi lter 572 catalytic combustion 572 scrubbing 572 Ohmic (Joule) heating 109–12 Operating line 299 Orifi ce fl owmeter 146 Osmotic dehydration 507 Osmotic pressure 242 Overall heat transfer coeffi cient U 100–102 Packaging materials 546–51 glass 549 mechanical properties 554–5 metals 548 optical properties 553–4 paper 549 polymers 549–51 transport properties 551–3 Packaging, food 545–60 active 557 controlled atmosphere (CAP) 557 environmental issues 558 modifi ed atmosphere (MAP) 557 objectives 545–6 vacuum 556 Paddle switch 147 Particle size distribution 155–60 Gaudin-Schuhmann distribution 159 log-normal distribution 159 normal distribution 158–9 Rosin-Ramler (Weibull) distribution 160 Particle size 154–5 Pasteur, Louis 355 Pasteurization 355 milk 387
Index 599 Peltier effect 414 , 418 Percent saturation (pychrometry) 462 Permeability 80 Phase transition 19–23 Physical properties 7–23 Piezoelectric transducer 145 Piping 56 Pitot tube fl owmeter 146 Plank’s equation 402–8 Plant layout 6 Pneumatic dryer 498 Pneumatic transport 65–8 positive pressure 65–6 vacuum 67–8 Polyethylene terephtalate (PET) 550 Polyethylene 550 Polystyrene 550 Ponchon-Savarit diagram 264–7 Pool boiling 436 Pot still 315 Powder fl ow 56–62 Power number (Po) 178–80 Prandl Number 82 Preservation 352 chemical 352 ionizing radiation 352 low temperature 352 reduction of water activity 352 thermal 352 Preservation processes 351 Presses 214–5 hydraulic 214 infl ated pouch 215 screw (expeller) 214 Process control 129–51 automatic 129 basic concepts 129–30 feedback 131 feed-forward 131–2 optimization 141 Process 130 Pseudoplastic fl uids 40 Psychrometry 461–4 Psychrophiles 396–7 Psychrotropes 396–7 Pulper-fi nisher 213–4 Pulsed electric fi elds 542 Pulsed intensive light 542 Pump selection 52–6 Pumps 46–55 centrifugal 46–9 diaphragm 50 positive displacement 49–52 progressing cavity (Moyno) 50–2 reciprocating 49 rotary 50 Purity (in sugar) 325 Rad (radiation dose unit) 537 Radiation dose 537–8 Rankine cycle 413 Raoult’s law 295 Raw materials 1 Rayleigh’s law 302 Reaction kinetics 115–128 Reaction order 116–119 fi rst order 118–9 rate constant 117 zero order 117 Reactors 123–4 continuous stirred tank (CSTR) 124–5 laminar fl ow 124 plug fl ow 124 Refl ectivity 96 Refractive index 148 Refrigerants 414 , 418–9 ozone depleting 419 Refrigerated transport 423 Refrigeration 391–412 , 413–28 mechanical 413–9 absorption 417–8 Regulation 129 Rehydration 503–4 Relative volatility 296 Residence time distribution (RTD) 123–6 cumulative distribution function 124–6 frequency density function 124–6 Residence time 123 Resistance thermometers 143 Retort 380–5 batch 380–3 continuous 383–5 crateless 380–1 Reverse osmosis (RO) 233 , 241–4 , 251–3 Reynolds Number (for mixing) 178–9 Reynolds Number 28–9 , 82 Rheological models 9 Bingham 9 Maxwell 9 Voight-Kelvin 9 600 Index Rheology 27 , 40–3 Rheopectic fl uids 41 Rittinger’s law 164–5 Rotameter 145–7 Rotary dryer 490 Rotary washer 569 Rubbery state 21 Sandiness in ice cream 317 Sanitation 561–92 Saran 550 Schmidt Number 83 Screw conveyor dryer 500–1 Seebeck coeffi cient 143 Segregation (in particulate solids) 184 Selective permeability 233 Semi-infi nite body 94–5 Sensor 130 , 142–8 color 148 composition 148 fl ow rate 145–7 level 147–8 pressure 144–5 temperature 142 Servo control 129 Set point Settling tank 218–9 Shear rate 28 Shear stress 28 Shelf life 351 Sherwood Number 83 Sieder-Tate equation 85 Sieving coeffi cient 237 Size reduction 153–73 energy consumption 163–5 forces 163 mechanism 163 Slab, steady state conduction 76 Slab, transient conduction 90–2 Soaker-washer 569 Solid-liquid extraction (leaching) 259 , 261–71 Sorption isotherm (water vapor) 16–19 Specifi c heat 10 Spin agitation 366 Spoilage, food 351 Spray dryer 492–7 “ Leafl ash ” atomization 495 air fl ow patterns 496–7 air heater 493 atomizer 493 bi-fl uid nozzle 495 control 497 pressure nozzle 494 ultrasonic atomization 495 Steady state 71 Steam injection 378 Steam-jet ejector 55–6 Sterilization 355 fl ame 365 , 383–4 Stoke’s law 35 Strain gages 144–5 Strain, defi nition 8 Stress, defi nition 8 compressive 9 shear 9 tensile 9 Structure 11–3 cellular 11 gels 12 emulsions 12 foams 12 powders 13 fi brous 11–2 Sublimation drying 512 Sublimation front 513 Sublimation 511–2 Supercritical carbon dioxide 273–4 Supercritical extraction applications 275–6 decaffeination of coffee 275 hops 275 Supercritical extraction systems 273–4 Supercritical fl uid (SCF) 271–3 as solvents 272–3 properties 271 Supersaturation 317 Surfactants 565–6 System response 133–6 fi rst order 133–5 second order 135–6 Tangential fi ltration 234–5 Temperature quotient, Q 10 120 Theoretical equivalent area, Σ 221 Thermal conductivity 73–4 Thermal diffusivity 73–4 Thermal processes 375–90
Index 601 Thermal processing 355–74 in-fl ow 369–73 , 386–8 in-package 364–9 , 385–6 optimization 363–4 Thermal properties 10–11 Thermistors 144 Thermocouples 143 Thermophiles 396–7 Thixotropic fl uids 41 Three-dimensional color space 148 Transmembrane pressure difference (TMPD) 235 Transmissivity 96 Transport phenomena 69–70 Triple point 512 Tubular centrifuge capacity 220–3 Tunnel dryer 487–8 Turbulent fl ow 28 , 36–9 around immersed particles 39 in tube 37–8 Ultrafi ltration (UF) 233 , 249–51 Unit operations 1–2 Vacuum closing 379 Van der Waals forces 57 Van’t Hoff ’s equation 242–3 Vapor compression cycle 413–7 Vapor recompression 446–7 mechanical 446 thermal 446–7 Vapor-liquid equilibrium (VLE) 295–8 Variables 130 controlled 130 manipulated 130 Venturi fl owmeter 146 View factor 99 Viscosity 27–8 Washing 568–70 Water activity 13–9 defi nition 14 determination 14 prediction 14–16 Water as plasticizer 21 Water in foods 13–4 Water softening 292–3 Wet bulb temperature 463 Whisky, distillation of 315 Williams-Landel-Ferry (WLF) equation 22 Yield locus 59 Young’s modulus 8 This page intentionally left blank Food Science and Technology Series List Maynard A. Amerine, Rose Marie Pangborn, and Edward B. Roessler, Principles of
Martin Glicksman, Gum Technology in the Food Industry. 1970. Maynard A. Joslyn, Methods in Food Analysis, second edition. 1970. C. R. Stumbo, Thermobacteriology in Food Processing, second edition. 1973. Aaron M. Altschul (ed.), New Protein Foods: Volume 1, Technology, Part A—1974. Volume 2, Technology, Part B—1976. Volume 3, Animal Protein Supplies, tải về 4.78 Mb. Chia sẻ với bạn bè của bạn:
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