Water in Foods (eBook)

Front Cover 1
Water in Foods: Fundamental Aspects and Their Significance 
4 
Copyright Page 5
Table Contents 8
Dedication 3
Preface 6
Acknowledgements 7
Chapter 1. Summary of Advances Reported at the ISOPOW-V Conference 12
1 PHYSICOCHEMICAL ASPECTS 12
2 BIOLOGICAL ASPECTS 16
3 TECHNOLOGICAL ASPECTS 20
Chapter 2. Basic Physical Chemistry and Links Between Hydration and Solute Interactions 24
ABSTRACT 24
INTRODUCTION 24
REFERENCES 36
Chapter 3. The Role of Conformation on the Thermodynamics and Rheology of Aqueous Solutions of Carbohydrate Polymers 38
ABSTRACT 38
INTRODUCTION 38
2 PRIMARY AND SECONDARY STRUCTURES OF FOOD POLYSACCHARIDES 39
3 THERMODYNAMICS OF SACCHARIDE SOLVATION AND CONFORMATION 41
4 INDUCED CONFORMATIONS THROUGH ION BINDING 44
5 EFFECT OF THE CONFORMATION ON THE RHEOLOGICAL PROPERTIES 48
6 CONCLUSIONS 52
ACKNOWLEDGEMENTS 52
REFERENCES 53
Chapter 4. Computer Modeling Studies of the Interaction of Water With Carbohydrates 54
ABSTRACT 54
INTRODUCTION 54
THEORETICAL MODELING 56
MD SIMULATIONS OF CARBOHYDRATES IN AQUEOUS SOLUTION 58
CONCLUSIONS 66
ACKNOWLEDGEMENTS 67
REFERENCES 67
Chapter 5. Protein-Stabilized Emulsions 70
ABSTRACT 70
INTRODUCTION 70
STRUCTURE OF A PURE PROTEIN LAYER 71
COMPETITIVE ADSORPTION OF PROTEINS 74
INFLUENCE OF SURFACTANTS ON PROTEIN LAYERS 78
PROTEIN-POLYSACCHARIDE INTERACTIONS 80
REFERENCES 83
Chapter 6. Water in Casein Gels How to Get it Out or Keep it In
ABSTRACT 86
INTRODUCTION 86
PHYSICAL STATE O F WATER IN CASEIN GELS 88
STRUCTURE OF CASEIN GELS 91
DYNAMIC ASPECTS OF GEL STRUCTURE 93
OTHER FACTORS OF IMPORTANCE 95
CONCLUSIONS 97
REFERENCES 98
Chapter 7. Theories of Liquid-Glass Transition 100
ABSTRACT 100
INTRODUCTION 101
STANDARD THEORIES: A SUMMARY 105
NEW APPROACHES 108
THE LIQUID-GLASS TRANSITION 116
DISCUSSION A N D CONCLUSION 118
REFERENCES 123
Chapter 8. Liquid Fragility and the Glass Transition in Water and Aqueous Solutions 126
ABSTRACT 126
INTRODUCTION 127
VISCOSITY AND THE GLASS TRANSITION IN PURE WATER A N D DILUTE SOLUTIONS 129
THE FREEZING OF DYNAMIC PROCESSES ABOVE Tg, IN RELATION TO LIQUID FRAGILITY 147
CONCLUDING REMARKS 150
ACKNOWLEDGEMENTS 150
REFERENCES 150
Chapter 9. Water and the Glass Transition — Dependence of the Glass Transition on Composition and Chemical Structure: Special Implications for Flour Functionality in Cookie Baking 154
ABSTRACT 154
POLYMER SCIENCE APPROACH TO THE GLASSY STATE PHENOMENON AND GLASS TRANSITIONS IN FOOD PRODUCTS AND PROCESSES 155
DEPENDENCE OF THE GLASS TRANSITION ON COMPOSITION AND CHEMICAL STRUCTURE 163
SPECIAL IMPLICATIONS FOR FLOUR FUNCTIONALITY IN COOKIE BAKING 176
CONCLUSIONS A N D FUTURE PROSPECTS 190
REFERENCES 190
Chapter 10. Water Diffusion and Sorption in Amorphous Macromolecular Systems and Foods 200
ABSTRACT 200
THE PHYSICS OF WATER TRANSPORT IN POLYMERS 201
ANALYSIS OF NON-FICKIAN TRANSPORT 203
WATER TRANSPORT BEHAVIOR IN A PLANE SHEET 203
TRANSPORT BEHAVIOR IN CYLINDRICAL AND SPHERICAL SAMPLES 209
EFFECT OF PARTICLE SIZE DISTRIBUTIONS ON WATER TRANSPORT BEHAVIOR 215
EFFECT OF VARIABLE BOUNDARY CONDITIONS ON PENETRANT TRANSPORT BEHAVIOR 218
REFERENCES 220
Chapter 11. NMR Imaging in the Study of Diffusion of Water in Foods 222
ABSTRACT 222
INTRODUCTION TO NMR IMAGING 223
DIFFUSION MEASUREMENTS 224
SATURATION MEASUREMENTS 226
APPLICATIONS 231
ACKNOWLEDGMENTS 233
REFERENCES 233
Chapter 12. Lipid Type and Location of the Relative Humidity Gradient Influence on the Barrier Properties of Lipids to Water Vapor 236
ABSTRACT 236
INTRODUCTION 236
EXPERIMENTAL PROCEDURES 238
RESULTS AND DISCUSSION 241
ACKNOWLEDGEMENTS 248
REFERENCES 248
Chapter 13. Changes in Rheological Properties of Gliadin as a Function of Temperature and Moisture: Development of a State Diagram 252
ABSTRACT 252
INTRODUCTION 252
MATERIALS A N D METHODS 254
RESULTS A N D DISCUSSION 254
STATE DIAGRAM 260
ACKNOWLEDGEMENT 262
REFERENCES 262
Chapter 14. Mechanical Properties of Frozen Model Solutions 264
ABSTRACT 264
INTRODUCTION 264
MATERIAL AND METHODS 267
RESULTS 268
DISCUSSION 277
CONCLUSION 278
REFERENCES 279
Chapter 15. Water Activity and Food Polymer Science: Implications of State on Arrhenius and WLF Models in Predicting Shelf Life 282
ABSTRACT 282
INTRODUCTION 282
MOISTURE AND REACTION RATES 283
TEMPERATURE DEPENDENCE OF CHEMICAL REACTIONS 289
CONCLUSIONS 297
ACKNOWLEDGEMENTS 298
REFERENCES 298
Chapter 16. Influence of the Low-Moisture State on pH and its Implication for Reaction Kinetics 302
ABSTRACT 302
INTRODUCTION 303
pH A N D REDUCED-MOISTURE SYSTEMS 304
pH A N D TEMPERATURE 308
WATER ACTIVITY AND REACTION KINETICS 309
REDUCED-MOISTURE/pH EFFECTS ON KINETICS IN T H E LITERATURE 318
ACKNOWLEDGEMENTS 320
REFERENCES 320
Chapter 17. Modelling of Vacuum Osmotic Dehydration of Food 324
ABSTRACT 324
INTRODUCTION 324
INFLUENCE OF STRUCTURE ON MASS TRANSFER 327
HDM MODELIZATION 327
HDM EXPERIMENTAL VERIFICATION 331
TYPICAL STEPS IN A MASS TRANSFER OPERATION BETWEEN A POROUS FOOD AND A LIQUID UNDER VACUUM CONDITION 333
HDM APPLICATIONS 335
CONCLUSIONS 338
REFERENCES 338
Chapter 18. Drying Modelling and Water Diffusivity in Carrots and Potatoes 340
ABSTRACT 340
NOTATION 340
INTRODUCTION 341
COMPLEXITY OF THE MODELS 343
TESTING DATA 352
CONCLUSIONS 356
ACKNOWLEDGEMENTS 358
REFERENCES 358
Chapter 19. The Role of Hydration in Lysozyme Structure and Activity: Relevance in Protein Engineering and Design 360
ABSTRACT 360
INTRODUCTION 360
MOLECULAR GROUP HYDRATION 362
DYNAMIC CHANGES 366
STRUCTURAL CHANGES 368
HYDRATION MODEL 370
HYDRATION IN PROTEIN FOLDING A N D PROTEIN ENGINEERING 372
ACKNOWLEDGEMENTS 374
REFERENCES 374
Chapter 20. The Role of Water in Biomembrane Structures 378
ABSTRACT 378
INTRODUCTION 378
THE STRUCTURE OF BIOMEMBRANES 379
THE BIOMEMBRANE CONSTITUENTS 380
WATER A N D BIOMEMBRANE STRUCTURE 383
DEHYDRATION EFFECTS 386
ANHYDROBIOSIS 388
CONCLUSIONS 389
ACKNOWLEDGEMENTS 389
REFERENCES 390
Chapter 21. Mechanisms Controlling Compatible Solute Accumulation: A Consideration of the Genetics and Physiology of Bacterial Osmoregulation 392
ABSTRACT 392
INTRODUCTION 392
POTASSIUM GLUTAMATE ACCUMULATION 394
CONCLUSIONS 404
ACKNOWLEDGEMENTS 405
REFERENCES 405
Chapter 22. Yeast Resistance to High Levels of Osmotic Pressure: Influence of Kinetics 410
ABSTRACT 410
1 INTRODUCTION 410
2 MATERIAL AND METHODS 412
4 CONCLUSIONS 417
REFERENCES 417
Chapter 23. Specific Solute Effects with Special Reference to Staphylococcus aureus 420
ABSTRACT 420
INTRODUCTION 420
STAPHYLOCOCCUS AUREUS AND SPECIFIC SOLUTE EFFECTS 422
MINIMAL WATER ACTIVITY FOR GROWTH OF STAPHYLOCOCCUS A UREUS 422
SOME PHYSICO-CHEMICAL CHANGES PRODUCED BY SOLUTE/S DISSOLUTION IN T H E GROWTH MEDIUM 423
ELECTRON MICROSCOPY OBSERVATIONS 424
CONCLUSIONS 429
ACKNOWLEDGMENTS 429
REFERENCES 429
Chapter 24. Further Developments in the Utilization of Hurdle Technology for Food Preservation 432
ABSTRACT 432
INTRODUCTION 432
OTHER APPLICATIONS 433
HURDLE TECHNOLOGY FOR ARMY PROVISIONS 434
ADDITIONAL HURDLES 436
BASIC ASPECTS 438
INTEGER FOODS 440
CONCLUSION 441
REFERENCES 441
Chapter 25. Combined Methods for the Preservation of Foods in Latin America and the CYTED-D Project 444
ABSTRACT 444
INTRODUCTION 444
THE 'HURDLE' CONCEPT AND COMBINED METHODS TECHNOLOGY 445
EXAMPLES OF DEVELOPMENTS IN CM TECHNOLOGY 447
POTENTIAL FACTORS TO BE USED IN C M 451
CONCLUSIONS 453
ACKNOWLEDGMENTS 455
REFERENCES 455
Chapter 26. IMF: An Iberoamerican Cooperative Project 456
REFERENCES 462
Chapter 27. Bacterial Ice-Nucleation Activity and its Application to Freeze Concentration of Fresh Foods for Modification of their Properties 464
ABSTRACT 464
1 ICE NUCLEATION (IN)-ACTIVE BACTERIA 465
2 PRELIMINARY TREATMENTS OF IN-ACTIVE BACTERIA FOR APPLICATIONS 467
3 FREEZE CONCENTRATION OF FOOD MATERIALS 468
REFERENCES 481
Chapter 28. Antifreeze Proteins 486
ABSTRACT 486
ZOOLOGY 486
MOLECULAR STRUCTURE 487
PHYSICAL BEHAVIOUR 489
PHYSICAL BEHAVIOUR 489
MECHANISM OF ANTIFREEZE ACTION 490
ANTIFREEZE POLYMERS IN FOOD TECHNOLOGY 491
REFERENCES 493
Chapter 29. The Glass Transition in the Freezing Process 494
ABSTRACT 494
REFERENCES 504
Chapter 30. Effect of Water Vapor on the Transport Properties of Oxygen through Polyamide Packaging Materials 506
ABSTRACT 506
INTRODUCTION 506
EXPERIMENTAL METHODS 507
RESULTS A N D DISCUSSION 508
CONCLUSIONS 517
REFERENCES 517
Chapter 31. Control of Water in Foods During Storage 520
ABSTRACT 520
INTRODUCTION 520
CLASSIFICATION OF FOODS 522
QUALITY ASPECTS O F FRESH FRUITS A N D VEGETABLES 522
CONTROL OF MOISTURE IN DRY FOODS 524
THE ROLE OF WATER IN MICROBIAL SPOILAGE 526
THE CAKING PHENOMENON 526
SORPTION RATES 528
SORPTION MEASUREMENTS 530
SHELF-LIFE PREDICTION BY IGC DATA 531
MATERIALS A N D METHODS 534
RESULTS 535
CONCLUSIONS 539
REFERENCES 539
Index 544