Modern food microbiology

Preface .................................................................................................... xv Part I. Historical Background .............................................................. 1 1. History of Microorganisms in Food .......................................................... 3 Historical Developments ................................................................... 4 Part II. Habitats, Taxonomy, and Growth Parameters ....................... 11 2. Taxonomy, Role, and Significance of Microorganisms in Foods ............ 13 Bacterial Taxonomy .......................................................................... 13 Primary Sources of Microorganisms Found in Foods ........................ 17 Synopsis of Common Foodborne Bacteria ....................................... 19 Synopsis of Common Genera of Foodborne Molds .......................... 24 Synopsis of Common Genera of Foodborne Yeasts ......................... 29 3. Intrinsic and Extrinsic Parameters of Foods That Affect Microbial Growth ..................................................................................................... 35 Intrinsic Parameters ......................................................................... 35 Extrinsic Parameters ........................................................................ 49 Combined Intrinsic and Extrinsic Parameters: The Hurdle Concept ...................................................................................... 53 Part III. Microorganisms in Foods ...................................................... 57 4. Fresh Meats and Poultry ......................................................................... 59 Biochemical Events That Lead to Rigor Mortis ................................. 60 The Biota of Meats and Poultry ........................................................ 60 Incidence/Prevalence of Microorganisms in Fresh Red Meats .......... 60 Microbial Spoilage of Fresh Red Meats ............................................ 68 Spoilage of Fresh Livers ................................................................... 76 Incidence/Prevalence of Microorganisms in Fresh Poultry ................ 77 Microbial Spoilage of Poultry ............................................................ 78 Carcass Sanitizing/Washing ............................................................. 81 vi Contents This page has been reformatted by Knovel to provide easier navigation. 5. Processed Meats ..................................................................................... 87 Curing .............................................................................................. 87 Smoking ........................................................................................... 89 Sausage, Bacon, Bologna, and Related Products ............................ 89 Bacon and Cured Hams ................................................................... 91 Fermented Meat Products ................................................................ 93 6. Seafoods .................................................................................................. 101 Microbiological Quality of Various Fresh and Frozen Products ......... 101 Fermented Fish Products ................................................................. 104 Spoilage of Fish and Shellfish .......................................................... 105 7. Fermentation and Fermented Dairy Products ......................................... 113 Fermentation .................................................................................... 113 Dairy Products .................................................................................. 119 Apparent Health Benefits of Fermented Milks ................................... 124 Diseases Caused by Lactic Acid Bacteria ......................................... 128 8. Fruit and Vegetable Products: Whole, Fresh-Cut, and Fermented ................................................................................................ 131 Fresh and Frozen Vegetables .......................................................... 131 Spoilage of Fruits ............................................................................. 141 Fresh-Cut Produce ........................................................................... 141 Fermented Products ......................................................................... 146 Miscellaneous Fermented Products .................................................. 154 9. Miscellaneous Food Products ................................................................. 163 Delicatessen and Related Foods ...................................................... 163 Eggs ................................................................................................. 164 Mayonnaise and Salad Dressing ...................................................... 167 Cereals, Flour, and Dough Products ................................................. 168 Bakery Products ............................................................................... 168 Frozen Meat Pies ............................................................................. 168 Sugar, Candies, and Spices ............................................................. 169 Nutmeats .......................................................................................... 169 Dehydrated Foods ............................................................................ 170 Enteral Nutrient Solutions (Medical Foods) ....................................... 171 Single-Cell Protein ............................................................................ 171 Contents vii This page has been reformatted by Knovel to provide easier navigation. Part IV. Determining Microorganisms and/or Their Products in Foods ........................................................................................ 177 10. Culture, Microscopic, and Sampling Methods ........................................ 179 Conventional Standard Plate Count .................................................. 179 Membrane Filters ............................................................................. 182 Microscope Colony Counts ............................................................... 184 Agar Droplets ................................................................................... 184 Dry Film and Related Methods ......................................................... 185 Most Probable Numbers ................................................................... 186 Dye Reduction .................................................................................. 186 Roll Tubes ........................................................................................ 187 Direct Microscopic Count .................................................................. 187 Microbiological Examination of Surfaces .......................................... 188 Metabolically Injured Organisms ....................................................... 190 Viable but Nonculturable Organisms ................................................ 194 11. Physical, Chemical, Molecular, and Immunological Methods ................ 201 Physical Methods ............................................................................. 201 Chemical Methods ............................................................................ 206 Methods for Characterizing and Fingerprinting Foodborne Organisms .................................................................................. 214 Immunological Methods .................................................................... 221 12. Bioassay and Related Methods .............................................................. 237 Whole-Animal Assays ....................................................................... 237 Animal Models Requiring Surgical Procedures ................................. 242 Cell Culture Systems ........................................................................ 243 Part V. Food Preservation and Some Properties of Psychrotrophs, Thermophiles, and Radiation-Resistant Bacteria ..................................................................................... 251 13. Food Preservation with Chemicals .......................................................... 253 Benzoic Acid and the Parabens ........................................................ 253 Sorbic Acid ....................................................................................... 255 The Propionates ............................................................................... 257 Sulfur Dioxide and Sulfites ............................................................... 257 viii Contents This page has been reformatted by Knovel to provide easier navigation. Nitrites and Nitrates .......................................................................... 258 NaCl and Sugars .............................................................................. 264 Indirect Antimicrobials ...................................................................... 265 Acetic and Lactic Acids ..................................................................... 268 Antibiotics and Bacteriocins .............................................................. 268 Antifungal Agents for Fruits .............................................................. 274 Ethylene and Propylene Oxides ....................................................... 274 Miscellaneous Chemical Preservatives ............................................. 275 14. Food Preservation with Modified Atmospheres ...................................... 283 Definitions ........................................................................................ 283 Primary Effects of CO2 on Microorganisms ....................................... 286 Food Products .................................................................................. 288 The Safety of MAP Foods ................................................................. 290 Spoilage of MAP and Vacuum-Packaged Meats .............................. 293 15. Radiation Preservation of Foods and Nature of Microbial Radiation Resistance ............................................................................... 301 Characteristics of Radiations of Interest in Food Preservation .......... 301 Principles Underlying the Destruction of Microorganisms by Irradiation ................................................................................... 303 Processing of Foods for Irradiation ................................................... 305 Application of Radiation .................................................................... 305 Radappertization, Radicidation, and Radurization of Foods ............. 306 Legal Status of Food Irradiation ........................................................ 312 Effect of Irradiation on Food Quality ................................................. 313 Storage Stability of Irradiated Foods ................................................. 315 Nature of Radiation Resistance of Microorganisms .......................... 315 16. Low-Temperature Food Preservation and Characteristics of Psychrotrophic Microorganisms .............................................................. 323 Definitions ........................................................................................ 323 Temperature Growth Minima ............................................................ 324 Preparation of Foods for Freezing .................................................... 324 Freezing of Foods and Freezing Effects ........................................... 325 Storage Stability of Frozen Foods .................................................... 327 Contents ix This page has been reformatted by Knovel to provide easier navigation. Effect of Freezing on Microorganisms .............................................. 327 Some Characteristics of Psychrotrophs and Psychrophiles .............. 331 The Effect of Low Temperatures on Microbial Physiologic Mechanisms ............................................................................... 333 Nature of the Low Heat Resistance of Psychrotrophs ....................... 336 17. High-Temperature Food Preservation and Characteristics of Thermophilic Microorganisms ................................................................. 341 Factors Affecting Heat Resistance in Microorganisms ...................... 342 Relative Heat Resistance of Microorganisms ................................... 346 Thermal Destruction of Microorganisms ........................................... 348 Some Characteristics of Thermophiles ............................................. 351 Other Aspects of Thermophilic Microorganisms ................................ 354 Canned Food Spoilage ..................................................................... 356 18. Preservation of Foods by Drying ............................................................. 363 Preparation and Drying of Low-Moisture Foods ................................ 363 Effect of Drying on Microorganisms .................................................. 364 Storage Stability of Dried Foods ....................................................... 366 Intermediate-Moisture Foods ............................................................ 367 19. Other Food Preservation Methods .......................................................... 375 High-Pressure Processing ................................................................ 375 Pulsed Electric Fields ....................................................................... 379 Aseptic Packaging ............................................................................ 380 Manothermosonication (Thermoultrasonication) ............................... 381 Part VI. Indicators of Food Safety and Quality, Principles of Quality Control, and Microbial Criteria ................................... 385 20. Indicators of Food Microbial Quality and Safety ..................................... 387 Indicators of Product Quality ............................................................ 387 Indicators of Food Safety .................................................................. 388 The Possible Overuse of Fecal Indicator Organisms ........................ 401 Predictive Microbiology/Microbial Modeling ...................................... 402 21. The HACCP System and Food Safety .................................................... 407 Hazard Analysis Critical Control Point System ................................. 407 Microbiological Criteria ..................................................................... 415 x Contents This page has been reformatted by Knovel to provide easier navigation. Part VII. Foodborne Diseases .............................................................. 423 22. Introduction to Foodborne Pathogens ..................................................... 425 Introduction ...................................................................................... 425 Host Invasion ................................................................................... 425 Pathogenesis .................................................................................... 428 Summary .......................................................................................... 434 23. Staphylococcal Gastroenteritis ................................................................ 441 Species of Concern in Foods ............................................................ 441 Habitat and Distribution .................................................................... 443 Incidence in Foods ........................................................................... 443 Nutritional Requirements for Growth ................................................. 444 Temperature Growth Range ............................................................. 444 Effect of Salts and Other Chemicals ................................................. 444 Effect of pH, Water Activity, and Other Parameters .......................... 444 Staphylococcal Enterotoxins: Types and Incidence .......................... 445 The Gastroenteritis Syndrome .......................................................... 453 Incidence and Vehicle Foods ............................................................ 454 Ecology of S. aureus Growth ............................................................ 455 Prevention of Staphylococcal and Other Food-Poisoning Syndromes ................................................................................. 455 24. Food Poisoning Caused by Gram-Positive Sporeforming Bacteria .................................................................................................... 461 Clostridium perfringens Food Poisoning ........................................... 461 Botulism ........................................................................................... 466 Bacillus Cereus Gastroenteritis ........................................................ 477 25. Foodborne Listeriosis .............................................................................. 485 Taxonomy of Listeria ........................................................................ 485 Growth .............................................................................................. 488 Distribution ....................................................................................... 492 Thermal Properties ........................................................................... 494 Virulence Properties ......................................................................... 497 Animal Models and Infectious Dose .................................................. 498 Incidence and Nature of the Listeriosis Syndromes .......................... 500 Resistance to Listeriosis ................................................................... 502 Contents xi This page has been reformatted by Knovel to provide easier navigation. Persistence of L. monocytogenes in Foods ...................................... 503 Regulatory Status of L. monocytogenes in Foods ............................. 504 26. Foodborne Gastroenteritis Caused by Salmonella and Shigella ............ 511 Salmonellosis ................................................................................... 511 Shigellosis ........................................................................................ 525 27. Foodborne Gastroenteritis Caused by Escherichia coli .......................... 531 Serological Classification .................................................................. 531 The Recognized Virulence Groups ................................................... 531 Prevention ........................................................................................ 543 Travelers' Diarrhea ........................................................................... 543 28. Foodborne Gastroenteritis Caused by Vibrio, Yersinia, and Campylobacter Species ........................................................................... 549 Vibriosis (Vibrio parahaemolyticus ) .................................................. 549 Other Vibrios .................................................................................... 552 Yersiniosis (Yersinia enterocolitica) .................................................. 556 Campylobacteriosis (Campylobacter jejuni) ...................................... 560 Prevention ........................................................................................ 563 29. Foodborne Animal Parasites ................................................................... 569 Protozoa ........................................................................................... 569 Flatworms ......................................................................................... 579 Roundworms .................................................................................... 584 30. Mycotoxins ............................................................................................... 595 Aflatoxins .......................................................................................... 595 Alternaria Toxins .............................................................................. 600 Citrinin .............................................................................................. 600 Ochratoxins ...................................................................................... 601 Patulin .............................................................................................. 601 Penicillic Acid .................................................................................... 602 Sterigmatocystin ............................................................................... 602 Fumonisins ....................................................................................... 602 Sambutoxin ...................................................................................... 606 Zearalenone ..................................................................................... 606 Control of Production ........................................................................ 606 xii Contents This page has been reformatted by Knovel to provide easier navigation. 31. Viruses and Some Other Proven and Suspected Foodborne Biohazards ............................................................................................... 611 Viruses ............................................................................................. 611 Bacteria and Prions .......................................................................... 616 Toxigenic Phytoplanktons ................................................................. 622 Appendices ............................................................................................ 629 Appendix A: Relationships of Common Foodborne Genera of Gram- Negative Bacteria .................................................................................... 629 Appendix B: Relationship of Common Foodborne Genera of Gram- Positive Bacteria ...................................................................................... 631 Appendix C: Biofilms ...................................................................................... 633 Appendix D: Grouping of the Gram-Negative Asporogenous Rods, Polar-Flagellate, Oxidase Positive, and Not Sensitive to 2.5 IU Penicillin, on the Results of Four Other Tests ......................................... 635 Index ....................................................................................................... 637