FOOD MICROBIOLOGY An Introduction SECOND EDITIONPDF电子书下载

SECTIONⅠBasics of Food Microbiology 1

1The Trajectory of Food Microbiology 3

Introduction 3

Who's on First? 3

Food Microbiology, Past and Present 4

To the Future and Beyond 8

Summary 10

Suggested reading 10

Questions for critical thought 10

2Factors That Influence Microbesin Foods 11

Introduction 11

Food Ecosystems, Homeostasis, and HurdleTechnology 12

Foods as Ecosystems 12

Classical Microbiology and Its Limitations 13

Limitations of Detection and Enumeration Methods 13

Homeostasis and Hurdle Technology 27

Growth Kinetics 29

Microbial Physiology and Metabolism 32

Carbon Flow and Substrate Level Phosphorylation 34

The Tricarboxylic Acid Cycle Links Glycolysis to AerobicRespiration 34

Conclusion 36

Summary 36

Suggested reading 36

Questions for critical thought 37

3Spores and Their Significance 39

Introduction 39

Spores in the Food Industry 39

Low-Acid Canned Foods 40

Bacteriology of Sporeformers of Public HealthSignificance 42

Heat Resistance of C.botulinum Spores 44

Spoilage of Acid and Low-Acid Canned and Vacuum-PackagedFoods by Sporeformers 46

Spore Biology 47

Structure 47

Macromolecules 48

Small Molecules 48

Dormancy 48

Resistance 49

Freezing and Desiccation Resistance 49

Pressure Resistance 50

γ-Radiation Resistance 50

UV Radiation Resistance 50

Chemical Resistance 50

Spore Heat Resistance 50

The Cycle of Sporulation and Germination 52

Sporulation 52

Activation 53

Germination 53

Outgrowth 54

Summary 54

Suggested reading 55

Questions for critical thought 55

4Detection and Enumeration of Microbesin Food 57

Introduction 57

Sample Collection and Processing 58

Analysis 58

Metabolism-Based Methods 61

Surface Testing 62

Summary 63

Suggested reading 63

Questions for critical thought 63

5Rapid and Automated Microbial Methods 65

Introduction 65

Sample Processing 66

Requirements and Validation of Rapid Methods 66

Rapid Methods Based on Traditional Methods 66

Immunologically Based Methods 69

Molecular Methods 72

Potpourri of Rapid Methods 74

Summary 75

Suggested reading 75

Questions for critical thought 76

6Indicator Microorganisms andMicrobiological Criteria 77

Introduction 77

The Purpose of Microbiological Criteria 77

The Need To Establish Microbiological Criteria 77

Definitions 78

Who Establishes Microbiological Criteria? 79

Sampling Plans 79

Types of Sampling Plans 80

Establishing Limits 81

Indicators of Microbiological Quality 81

Indicator Microorganisms 82

Metabolic Products 83

Indicators of Foodborne Pathogens and Toxins 84

Indicator Organisms 86

Fecal Coliforms and E.coli 88

Metabolic Products 88

Application and Specific Proposals for MicrobiologicalCriteria for Food and Food Ingredients 89

Current Status 90

Summary 93

Suggested reading 93

Questions for critical thought 93

SECTIONⅡGram-Negative Foodborne Pathogenic Bacteria 95

7Salmonella Species 97

Outbreak 97

Introduction 97

Characteristics of the Organism 100

Biochemical Identification 100

Taxonomy and Nomenclature 101

Serological Identification 101

Physiology 102

Reservoirs 105

Characteristics of Disease 106

Symptoms and Treatment 106

Preventative Measures 107

Antibiotic Resistance 107

Infectious Dose 108

Pathogenicity and Virulence Factors 109

Specific and Nonspecific Human Responses 109

Attachment and Invasion 109

Growth and Survival within Host Cells 110

Virulence Plasmids 110

Other Virulence Factors 110

Summary 111

Suggested reading 112

Questions for critical thought 112

8Campylobacter jejuni 113

Outbreak 113

Introduction 113

Characteristics of the Organism 114

Environmental Susceptibility 114

Reservoirs and Foodborne Outbreaks 114

Characteristics of Disease 117

C.jejuni and C.coli 117

Other Campylobacter Species 117

Epidemiologic Subtyping Systems Useful forInvestigating Foodborne Illnesses 117

Infective Dose and Susceptible Populations 118

Virulence Factors and Mechanismsof Pathogenicity 118

Cell Association and Invasion 119

Flagella and Motility 119

Toxins 120

Other Factors 120

Autoimmune Diseases 120

Immunity 120

Summary 120

Suggested reading 121

Questions for critical thought 121

9Enterohemorrhagic Escherichia coli 123

Outbreak 123

Introduction 124

Categories of E.coli 124

Characteristics of E.coli O157:H7 and Non-O157:H7EHEC 128

Acid Tolerance 128

Antibiotic Resistance 129

Inactivation by Heat and Irradiation 129

Reservoirs of E.coli O157:H7 130

Detection of E.coli O157:H7 and EHEC on Farms 130

Factors Associated with Bovine Carriage of E.coliO157:H7 130

Cattle Model for Infection by E.coli O157:H7 130

Domestic Animals and Wildlife 130

Humans 131

Disease Outbreaks 131

Geographic Distribution 131

Seasonality of E.coli O157:H7 Infection 132

Age of Patients 132

Transmission of E.coli O157:H7 132

Examples of Foodborne and Waterborne Outbreaks 133

Characteristics of Disease 135

Infectious Dose 135

Mechanisms of Pathogenicity 135

Attaching and Effacing 136

The Locus of Enterocyte Effacement 137

The 60-MDa Plasmid （pO157） 137

Stxs 137

Conclusion 139

Summary 139

Suggested reading 140

Questions for critical thought 140

10Yersinia enterocolitica 141

Outbreak 141

Introduction 141

Characteristics of the Organism 141

Classification 142

Susceptibility and Tolerance 143

Characteristics of Infection 144

Reservoirs 145

Foodborne Outbreaks 146

Mechanisms of Pathogenicity 147

Pathological Changes 147

Virulence Determinants 147

Chromosomal Determinants of Virulence 147

Other Virulence Determinants 148

Pathogenesis of Yersinia-Induced Autoimmunity 148

Summary 149

Suggested reading 149

Questions for critical thought 149

11Shigella Species 151

Outbreak 151

Introduction 151

Classification and Biochemical Characteristics 154

Shigella in Foods 154

Survival and Growth in Foods 155

Characteristics of Disease 155

Foodborne Outbreaks 156

Virulence Factors 157

Genetic Regulation 157

Conclusions 158

Summary 158

Suggested reading 158

Questions for critical thought 158

12Vibrio Species 161

Outbreak 161

Introduction 161

Characteristics of the Organism 162

Epidemiology 162

Characteristics of Disease 163

Susceptibility to Physical and Chemical Treatments 163

V.cholerae 163

V.mimicus 165

V.parahaemolyticus 166

V.vulnificus 167

V.fluvialis, V.furnissii, V.hollisae, and V.alginolyticus 168

Summary 169

Suggested reading 169

Questions for critical thought 170

SECTION Ⅲ Gram-Positive Foodborne Pathogenic Bacteria 171

13Listeria monocytogenes 173

Outbreak 173

Introduction 174

Characteristics of the Organism 175

Classification 175

Susceptibility to Physical and Chemical Agents 176

Listeriosis and Specific Foods 176

Ready-to-Eat Foods 176

Milk Products 177

Cheeses 177

Meat and Poultry Products 177

Seafoods 178

Other Methods of Food Preservation 178

Sources of L.monocytogenes in the Environment 178

Food-Processing Plants 179

Prevalence and the Regulatory Status of L.monocytogenes 180

Human Carriers 181

Foodborne Outbreaks 182

Characteristics of Disease 184

Infectious Dose 184

Virulence Factors and Mechanisms of Pathogenicity 185

Pathogenicity of L.monocytogenes 185

Specific Genes Mediate Pathogenicity 186

Summary 186

Suggested reading 187

Questions for critical thought 187

More questions than answers 187

14 Staphylococcus aureus 189

Outbreak 189

Characteristics of the Organism 190

Historical Aspects and General Considerations 190

Sources of Staphylococcal Food Contamination 190

Resistance to Adverse Environmental Conditions 191

Foodborne Outbreaks 192

Incidence of Staphylococcal Food Poisoning 192

A Typical Large Staphylococcal Food Poisoning Outbreak 193

Characteristics of Disease 193

Infective Dose and Susceptible Populations 194

Numbers of Staphylococci Required 194

Toxin Dose Required 194

Microbiology, Toxins, and Pathogenicity 195

Nomenclature, Characteristics, and Distribution ofStaphylococcal Enterotoxin-Producing Staphylococci 195

Introduction to, and Nomenclature of, the Staphylococcal Enterotoxins 195

Staphylococcal Regulation of Staphylococcal Enterotoxin Expression 196

Summary 200

Suggested reading 200

Questions for critical thought 200

15Clostridium botulinum 203

Introduction 203

Four Faces of Botulism 203

Characteristics of the Disease 208

Toxic and Infectious Doses and SusceptiblePopulations 208

Characteristics of C.botulinum 209

Classification 209

Tolerance of Preservation Methods 211

Sources of C.botulinum 213

Occurrence of C.botulinum in the Environment 213

Occurrence of C.botulinum in Foods 213

Virulence Factors and Mechanismsof Pathogenicity 215

Structure of the Neurotoxins 215

Genetic Regulation of the Neurotoxins 216

Mode of Action of the Neurotoxins 217

Summary 218

Suggested reading 218

Questions for critical thought 218

16Clostridium perfringens 221

The Foodborne Illness 221

A Spore's-Eye View of C.perfringensToxicoinfections 221

A Human View of C.perfringens Type A Foodborne Illness 221

Incidence 222

Food Vehicles for C.perfringens Foodborne Illness 222

Factors Contributing to C.perfringens Type A Foodborne Illness 222

Preventing C.perfringens Type A Foodborne Illness 223

Identification of C.perfringens Type A Foodborne Illness Outbreaks 223

Characteristics of C.perfringens Type A Foodborne Illness 224

Infectious Dose for C.perfringens Type A Foodborne Illness 224

The Organism 224

Overview 224

Classification: Toxin Typing of C.perfringens 226

Susceptibility of C.perfringens to Preservation Methods 227

Reservoirs for C.perfringens Type A 227

Virulence Factors Contributing to C.perfringens Type A Foodborne Illness 228

Heat Resistance 228

C.perfringens Enterotoxin 228

Summary 230

Suggested reading 230

Questions for critical thought 231

17Bacillus cereus 233

Outbreak 233

Introduction 233

Characteristics of the Organism 234

Environmental Sources 234

Foodborne Outbreaks 235

Characteristics of Disease 236

Dose 236

Virulence Factors and Mechanisms of Pathogenicity 237

The Emetic Toxin 237

Enterotoxins 237

The Spore 238

Summary 238

Suggested reading 239

Questions for critical thought 239

SECTION ⅣVOther Microbes Important in Food 241

18 Lactic Acid Bacteria and Food Fermentations 243

Introduction 243

The Biochemical Foundation of Food Fermentation 243

Catabolic Pathways 245

Dairy Fermentations 246

Starter Cultures 248

Production of Aroma Compounds 249

Genetics of Lactic Acid Bacteria 250

Fermented Vegetables 250

Ingredients and Additives Used during Fermentations 251

Sauerkraut Fermentation 251

Pickle Fermentation 252

Meat Fermentations 253

Summary 254

Suggested reading 254

Questions for critical thought 254

19Yeast-Based and Other Fermentations 257

Introduction 257

Fermentations That Use Yeast 258

Bread 258

Beer 259

Wine 261

Vinegar Fermentation 263

Cocoa and Coffee Fermentations 264

Cocoa 264

Coffee 268

Fermented Foods of Non-Western Societies 268

Summary 269

Suggested reading 269

Questions for critical thought 269

20 Spoilage Organisms 271

Introduction 271

Meat, Poultry, and Seafood Products 272

Origin of Microflora in Meat 272

Origin of Microflora in Poultry 272

Origin of Microflora in Finfish 272

Origin of Microflora in Shellfish 273

Bacterial Attachment to Food Surfaces 273

Microbial Progression during Storage 273

Muscle Tissue as a Growth Medium 275

Factors Influencing Spoilage 276

Control of Spoilage of Muscle Foods 278

Milk and Dairy Products 281

Milk and Dairy Products as Growth Media 281

Psychrotrophic Spoilage 283

Spoilage by Fermentative Nonsporeformers 286

Spore-Forming Bacteria 287

Yeasts and Molds 288

Spoilage of Produce and Grains 289

Types of Spoilage 289

Mechanisms of Spoilage 291

Influence of Physiological State 291

Microbiological Spoilage of Vegetables 292

Microbiological Spoilage of Fruits 295

Microbiological Spoilage of Grains and Grain Products 296

Summary 298

Suggested reading 298

Questions for critical thought 298

21 Molds 301

Introduction 301

Isolation, Enumeration, and Identification 301

Aspergillus Species 304

A.flavus and A.parasiticus 308

Other Toxigenic Aspergilli 312

Penicillium Species 313

Significant Penicillium Mycotoxins 313

Fusaria and Toxigenic Molds Other than Aspergilli and Penicillia 316

Toxigenic Fusarium Species 316

Other Toxic Molds 319

Summary 319

Suggested reading 320

Questions for critical thought 320

22 Viruses and Prions 321

Introduction 321

Viruses 322

Elementary Virology 322

Viruses as Agents of Foodborne Illness 323

Bacteriophages in the Dairy Industry 327

Beneficial Uses of Viruses 328

Prions 329

A Short History of the Prion 330

Prion Biology 331

Summary 332

Suggested reading 332

Questions for critical thought 332

SECTIONⅤ Control of Microorganisms in Food 335

23Antimicrobial Preservatives 337

Introduction 337

Factors That Affect Antimicrobial Activity 338

Organic Acids 339

Parabenzoic Acids 340

Nitrites 341

Phosphates 341

Sodium Chloride 341

Disinfectants 342

Sulfites 342

Chlorine 343

Quaternary Ammonium Compounds 343

Peroxides 344

Ozone 344Naturally Occurring Antimicrobials 344

Lysozyme 344

Lactoferrin and Other Iron-Binding Proteins 345

Avidin 345

Spices and Their Essential Oils 346

Onions and Garlic 347

Isothiocyanates 347

Phenolic Compounds 347

Summary 348

Suggested reading 348

Questions for critical thought 348

24 Biologically Based Preservation and Probiotic Bacteria 351

Introduction 351

Biopreservation by Controlled Acidification 352

Bacteriocins 352

General Characteristics 352

Bacteriocin Applications in Foods 354

Probiotic Bacteria 357

The Human GI Tract Is a Microbia Ecosystem 358

Summary 360

Suggested reading 360

Questions for critical thought 360

25 Physical Methods of Food Preservation 363

Introduction 363

Physical Dehydration Processes 363

Drying 363

Freeze-Drying 364

Cool Storage 364

Controlled-Atmosphere Storage 365

Modified-Atmosphere Packaging 365

Freezing and Frozen Storage 366

Preservation by Heat Treatments 367

Technological Fundamentals 367

Thermobacteriology 369

Calculating Heat Processes for Foods 374

Microwave Heat Treatment 375

Preservation by Irradiation 375

UV Radiation 375

Ionizing Radiation 375

Microbiological Fundamentals 376

Technological Fundamentals 378

Consumer Acceptance of Food Irradiation 379

Other Nonthermal Processes 381

Summary 383

Suggested reading 383

Questions for critical thought 383

26 Industrial Strategies for Ensuring Safe Food 387

Introduction 387

GMPs 387

General Provisions （Subpart A） 388

Buildings and Facilities （Subpart B） 388

Equipment （Subpart C） 389

Production and Process Controls （Subpart E） 389

DALs （Subpart G） 390

Sanitation 390

SSOPs 393

HACCP 394

Conclusion 401

Summary 401

Suggested reading 401

Questions for critical thought 402

Glossary 403

Answers to Puzzles 409

Index 413