xxviii ◾ Contents
Nature of Process ...................................................................................................461
Nature of Food ..................................................................................................... 462
Nature of Microorganisms .................................................................................... 463
Methods ........................................................................................................................ 463
Ice Chilling ........................................................................................................... 463
Refrigeration ......................................................................................................... 463
Freezing ................................................................................................................ 464
Conclusion ..................................................................................................................... 464
References .......................................................................................................................465
35 Control by Reduced Water Activity and Drying ......................................................467
Introduction .................................................................................................................. 467
Objectives ...................................................................................................................... 467
Mechanism of Action..................................................................................................... 468
Influencing Factors ........................................................................................................ 468
Nature of Process .................................................................................................. 468
Nature of Foods .................................................................................................... 469
Nature of Microorganisms .................................................................................... 469
Methods .........................................................................................................................471
Natural Dehydration .............................................................................................471
Mechanical Drying ................................................................................................471
Freeze Drying ........................................................................................................472
Foam Drying .........................................................................................................473
Smoking ................................................................................................................473
Intermediate Moisture Foods .................................................................................473
Conclusion ......................................................................................................................473
References .......................................................................................................................474
36 Control by Low pH and Organic Acids ....................................................................475
Introduction ...................................................................................................................475
Objectives .......................................................................................................................476
Mechanisms of Antimicrobial Action .............................................................................476
Influencing Factors ........................................................................................................ 477
Nature of Acids ..................................................................................................... 477
Nature of Foods .....................................................................................................478
Nature of Microorganisms .....................................................................................478
Acids Used ......................................................................................................................478
Acetic Acid ............................................................................................................478
Propionic Acid .......................................................................................................478
Lactic Acid ............................................................................................................ 480
Citric Acid ............................................................................................................ 480
Sorbic Acid ........................................................................................................... 480
Benzoic Acid ......................................................................................................... 480
Parabens (Esters of p-Hydroxybenzoic Acid) .........................................................481
Conclusion ......................................................................................................................481
References ...................................................................................................................... 482
Nature of Process ...................................................................................................461
Nature of Food ..................................................................................................... 462
Nature of Microorganisms .................................................................................... 463
Methods ........................................................................................................................ 463
Ice Chilling ........................................................................................................... 463
Refrigeration ......................................................................................................... 463
Freezing ................................................................................................................ 464
Conclusion ..................................................................................................................... 464
References .......................................................................................................................465
35 Control by Reduced Water Activity and Drying ......................................................467
Introduction .................................................................................................................. 467
Objectives ...................................................................................................................... 467
Mechanism of Action..................................................................................................... 468
Influencing Factors ........................................................................................................ 468
Nature of Process .................................................................................................. 468
Nature of Foods .................................................................................................... 469
Nature of Microorganisms .................................................................................... 469
Methods .........................................................................................................................471
Natural Dehydration .............................................................................................471
Mechanical Drying ................................................................................................471
Freeze Drying ........................................................................................................472
Foam Drying .........................................................................................................473
Smoking ................................................................................................................473
Intermediate Moisture Foods .................................................................................473
Conclusion ......................................................................................................................473
References .......................................................................................................................474
36 Control by Low pH and Organic Acids ....................................................................475
Introduction ...................................................................................................................475
Objectives .......................................................................................................................476
Mechanisms of Antimicrobial Action .............................................................................476
Influencing Factors ........................................................................................................ 477
Nature of Acids ..................................................................................................... 477
Nature of Foods .....................................................................................................478
Nature of Microorganisms .....................................................................................478
Acids Used ......................................................................................................................478
Acetic Acid ............................................................................................................478
Propionic Acid .......................................................................................................478
Lactic Acid ............................................................................................................ 480
Citric Acid ............................................................................................................ 480
Sorbic Acid ........................................................................................................... 480
Benzoic Acid ......................................................................................................... 480
Parabens (Esters of p-Hydroxybenzoic Acid) .........................................................481
Conclusion ......................................................................................................................481
References ...................................................................................................................... 482