The Science of Meat Quality Book

Contributors xv

Chapter 1 Growth of Muscle from the Myoblast toWhole Muscle 1

Terry Brandebourg

Introduction 1

Overview of Skeletal Muscle Development 1

Types of Muscle 2

Structure of Muscle 3

Organization of Whole Muscle 4

Fiber-Type Development 5

Hyperplasia (Prenatal Muscle Development) 6

Overview 6

Embryogenesis of Muscle 7

Myogenesis 9

Biphasic Fiber Formation 12

Hypertrophy (Postnatal Muscle Development) 12

Satellite Cells 14

Protein Turnover 14

Protein Synthesis 15

Protein Degradation 15

Muscle Cell Culture 16

Basic Concepts of Cell Culture 17

Culture of Established Muscle Cell Lines—Murine C2C12 Myoblasts 20

Propagation 21

Subculturing 21

Cell Quantification 22

Induction of Differentiation and Fusion 22

Cryopreservation 23

Thawing Cryopreserved Stocks 24

References 25

Chapter 2 Animal Growth and Empty Body Composition 29

Michael Dikeman

Composition of the Empty Body from Birth to Harvest 29

Chemical Composition 33

Physical Separation 37

Magnetic Resonance Imaging 38

X-Ray Computed Tomography Scanning 39

Near-Infrared Reflectance 39

Total Body Electromagnetic Conductivity (TOBEC) 40

Dual-Energy X-Ray Absorptiometry 40

Video Image Analysis 42

40K Liquid Scintillation Counter 43

Dilution Techniques 44

Ultrasound Technology 44

Specific Gravity 45

Carcass Yields of Closely Trimmed Retail Product or Fat-Free Lean 45

Summary 46

References 46

Chapter 3 Muscle Structure and Cytoskeletal Proteins 49

Chris R. Kerth

Introduction 49

Connective Tissue 49

Organizational Structure of Muscle 53

Muscle Cell Structure 54

Proteins of the Muscle 56

Contractile Proteins 56

Z-disk Protein 59

Gap Filaments 59

Intermediate Filaments 60

Costameric Proteins 60

Isolating Myofibrillar Proteins 60

Purifying Myofibrils 60

Procedure 61

Result 62

References 63

Chapter 4 Muscle Metabolism and Contraction 65

Chris R. Kerth

Introduction 65

Metabolism 65

Glycolysis 65

Oxidative Phosphorylation 66

Muscle Contraction 66

Nerve Impulse 67

Relaxation 71

Muscle Fiber Types 71

Fiber Typing Procedure—Combined Stain for Identifying Muscle Fiber Types 73

Principle 73

Solutions 73

Staining Sequence for Bovine 75

Staining Sequence for Ovine 75

Staining Sequence for Porcine 76

Chemicals Needed for Staining Procedures 77

References 77

Chapter 5 Converting Muscle to Meat: The Physiology of Rigor 79

Kirk W. Braden

Introduction 79

Muscle Metabolism upon Exsanguination 79

Development of Meat Quality 81

Water-Holding Capacity 82

Meat Color 83

Aging and Tenderness 84

Antemortem Factors 85

Genetics 85

Stress and Diet 87

Postmortem Factors 89

Protein Proteolysis 89

Calpains 90

Cathepsins 90

Muscle Ultrastructure 90

Temperature and Chilling 91

Electrical Stimulation 91

Analysis of Muscle pH 92

Taking the Measurement 92

Analysis of Sarcomere Length 93

Solutions 93

0.1 M NaHPO4 Buffer at pH 7.2 93

0.2 M Sucrose in 0.1 M NaHPO4 Buffer at pH 7.2 93

Preparation of Muscle for Laser Diffraction 94

Sarcomere Length Determination 94

References 94

Chapter 6 Meat Tenderness 99

Chris R. Kerth

Introduction 99

What is Tenderness? 99

Factors that Affect Tenderness 100

Sarcomere Contractile State 100

Myofibrillar Protein Degradation 101

Connective Tissue 103

Background Effect 106

Measuring Tenderness 106

Shear Force 106

Sarcomere Length 107

Protein Degradation 109

Connective Tissue 110

MFI Procedure (Myofibrillar Fragmentation Index) 110

References 116

Chapter 7 Water-Holding Capacity of Meat 119

Jason K. Apple and Janeal W.S. Yancey

Introduction 119

Postmortem Muscle Metabolism and the WHC of Meat 120

Drip Channels and Postmortem Aging 121

Manipulating the WHC of Meat 124

Salt 124

Phosphates 125

Acid Marination 126

Factors Influencing the WHC of Meat 127

Genetics 127

Preslaughter Animal Management 130

Nutrition 131

Carcass/Meat Chilling 133

Electrical Stimulation 133

Methods of Measuring the WHC of Meat 133

Gravitational Drip Loss 134

Drip Tubes 134

Filter-Paper Press 134

Centrifugation 135

References 136

Chapter 8 Lipids and Lipid Oxidation 147

Kyle Willian

Introduction 147

Structure, Nomenclature, and Classification of Meat Lipids 147

Fatty Acids 148

Neutral Lipids 151

Polar Lipids 152

Saponifiable and Nonsaponifiable Lipids 155

Composition of Lipids in Meat 156

Extraction of Lipids 157

Total Lipids 157

Nonsaponifiable Lipids 158

Analyses 158

Fatty Acid Methyl Esters 158

Chromatography 160

Gas Chromatography 161

High-Performance Liquid Chromatography 165

Lipid Oxidation in Muscle Foods 165

Basic Chemistry of Lipid Oxidation 165

Enzyme and Nonenzyme Reactive Oxygen Species 169

Measurement of Oxidation 170

Volatile Products, Sensory Evaluation, and Headspace Gas

Chromatography 170

Primary Changes 171

Secondary Changes 171

Procedures 172

TBARS 172

Folch Total Lipids Extraction 172

Direct Transesterification (Methylation) of Fatty Acids 173

Nonsaponifiable (Cholesterol, Fat-Soluble Vitamins) Standard Solutions 173

Extraction and Sample Preparation for Nonsaponifiable Lipids: Cholesterol,

Fat-Soluble Vitamins, Carotenoids 174

Gas Chromatography (GC) 174

High-Performance Liquid Chromatography (HPLC) 174

References 175

Chapter 9 Meat Color 177

Richard Mancini

Introduction 177

Meat Color Chemistry 177

Deoxymyoglobin 177

Oxymyoglobin 180

Carboxymyoglobin 180

Metmyoglobin 180

Oxygen Consumption 180

Metmyoglobin Reduction 181

Deoxygenation and Subsequent Reoxygenation 181

Hemoglobin 181

Antemortem Factors Affecting Meat Color 181

Genetics 182

Postmortem Factors Affecting Meat Color 182

Temperature and Case-Ready Packaging 182

Laboratory Analyses of Raw Meat Surface Color 183

Visual Surface Color Evaluation 184

Instrumental Surface Color Evaluation 186

Determination of Myoglobin Redox State in Meat Extracts 187

Myoglobin Isolation from Beef Samples 187

Preparing Oxymyoglobin in Purified Solutions 188

Preparing Carboxymyoglobin in Purified Solutions 188

Metmyoglobin Reducing Activity (MRA) 189

Aerobic Reducing Activity 189

Oxygen Consumption 190

Surface Myoglobin Oxygenation 190

Depth of Oxygenation 190

Mitochondrial Isolation and Oxygen Consumption Measurement 191

Cooked Color 192

Iridescence 193

Cured Color and NO-Myoglobin 194

Bone Marrow Discoloration 194

New Developments in Color Research Using Proteomics 195

Conclusion 195

References 196

Chapter 10 Meat Cookery 199

Clinton Rowe and Chris R. Kerth

Cooking Loss 199

Maillard Reaction and Flavor Impacts 200

Soluble and Insoluble Collagen 201

Cookery Methods 202

Fast versus Slow Cookery 202

Dry Heat Cookery 202

Moist Heat Cookery 203

Smoking 203

Microwave 204

Cooked Color 204

Conclusion 205

References 205

Chapter 11 Trained Sensory Panels 207

Christy L. Bratcher

Introduction and History 207

Trained Panels and Sensory Attributes 208

Panel Training 209

Procedures 210

References 213

Chapter 12 Untrained Sensory Panels 215

Patricia C. Curtis

Introduction 215

Testing Locations 215

In-House Testing 215

Central Location Testing 216

In-Home Testing 216

Panel Considerations 216

Human Subject 217

Recruiting Panelists 217

Panel Selection 217

Panel Size and Replication 218

Sensory Methods 220

Discrimination Testing 220

Triangle Tests 220

Duo–Trio Tests 220

Constant Duo–Trio Tests 222

Balanced Reference Duo–Trio Test 222

Paired Comparison Tests 222

Directional Paired Comparison Test 224

Difference Paired Comparison Test (Simple Difference Test) 224

Ranking Tests 224

Acceptance and Preference Testing 225

Preference Tests 225

Paired Preference Tests 225

Nonforced Preference Tests 227

Option 1 227

Option 2 227

Option 3 227

Option 4 227

Preference Ranking 228

Acceptance Tests 228

Hedonic Scales 228

Summary 230

References 231

Chapter 13 Consumer Sensory Panels 233

Ryan Cox

Developing an Experimental Approach 234

Acceptance versus Preference 234

Types of Acceptance and Preference Tests 234

Data Collection 236

The Written Survey 239

Types of Questions 240

Identifying Test Subjects 240

Source of Test Subjects 242

Choice of Test Location 242

Laboratory Testing 242

Public Venue Testing 243

Consumer Home Testing 243

Additional Considerations 243

Conducting Consumer Testing 244

Consumer Testing Procedures 244

Samples 244

Product Preparation 245

Product Presentation and Sample Number 246

Execution of the Consumer Test 246

Incentives and Compensation 247

Data Analysis 247

References 247

Chapter 14 Preventing Foodborne Illness 249

Michael A. Davis

Introduction 249

Parameters that Affect Microbial Growth 249

Intrinsic Parameters 249

pH 250

Oxidation–Reduction Potential (Eh) 250

Moisture Content 251

Nutrient Content 252

Antimicrobial Factors 252

Biological Structures 253

Extrinsic Parameters 253

Product Storage Temperature 253

Relative Humidity 253

Atmospheric Conditions 254

Presence of Other Microbes and Their Activity 254

Prevention of Foodborne Illness—Processing Operations and Management Tools 254

Good Manufacturing Practices 254

Facilities and Premises 255

Sanitation 255

Equipment 255

Incoming Material 255

Employees and Personnel 256

Processing Operations 256

Pest Control 256

Hazard Analysis and Critical Control Points 256

Food Safety Objectives and Performance Objectives 257

Chemical Food Protection and Preservation 258

Chemical Sanitizing Agents 258

Chlorine and Chlorine Compounds 258

Electrolyzed Water 259

Ozone 259

Hydrogen Peroxide 259

Acidified Sodium Chlorite 259

Cetylpyridinium Chloride 260

Chemical Preservative Agents 261

Organic Acids (Acetic and Lactic) 261

Sorbic Acid/Sorbates 261

Sulfites and Sulfur Dioxide 262

Propionic Acid/Propionates 262

Nitrites and Nitrates 262

Benzoic Acid 262

Other Chemical Preservatives 262

Ethanol 262

Chitosans 263

Indirect Antimicrobial Chemicals 263

Flavoring Compounds 263

Antioxidant Compounds 264

Phosphates 264

Other Indirect Antimicrobial Chemicals 264

Competitive Exclusion and Interference 264

Prebiotics, Probiotics, Bacteriophages, and Bacteriocins 265

Physical Food Protection and Preservation 265

Modified Atmospheres 265

General Effects of Carbon Dioxide on Microorganisms 265

Modified Atmosphere Packaging 266

Vacuum Packaging 266

Controlled Atmospheres 266

Radiation and the Electromagnetic Spectrum 267

Gamma Rays or Gamma Radiation 267

Electron Beams 268

Ultraviolet Light 269

Microwave Energy 269

High-Temperature Protection 269

Heat Destruction and Thermal Death Time 270

D Value 270

z Value 270

Safe Harbor Lethality and the 12D Concept 271

Low-Temperature Protection 272

Thawing 273

Low-Moisture Protection 273

Microbial Indicators and Sampling Plans 273

Product Quality Prediction by Microbial Numbers 274

Product Safety Prediction by Microbial Numbers 274

Microbial Sampling Plans 275

Attribute Sampling Plans 275

Microbiological Sampling of the Environment 279

Common Microbiological Culturing Methods 279

Most Probable Number Method 280

Plate Count Method 280

Direct Microscopic Count Method 281

Dye Reduction Method 281

Other Microbial Methods 281

References 281

Index 283

A color plate section is located between pages 192 and 193.