Food Texturology: Measurement and Perception of Food Textural Properties

The concept behind this book is to take a holistic view of food texture, starting with the determination of food texture, its perception in the mouth, and its measurement by both sensory and instrumental methods, and to examine the relation between them. The book has been divided into four sections: Fundamentals, Sensory and Human Interactions, Instrumental Analysis, and Food Products. Essentially we cover the techniques used for measuring food texture, and then apply them to the different product groups. Readers of the first edition will notice the title has changed, with the adoption of the term texturology . In the long history of food texture research, texturology has been occasionally used in literature. The term texturology has not been widely accepted by texture researchers (texturologists) because of their concern over whether the theories and techniques are broad and strong enough to support texture research as a scientific discipline. During the 24 years since the publication of the first edition, the editors have observed vast developments in theories as well as the assessment methodology of food texture (both sensory and instrumental) and these have shaped our understanding. This second edition brings the science up to date by introducing topics not previously covered (e.g. psychophysics, tribology, oral processing, texture maps and special foods for dysphagia patients). It includes an exposé of the instruments to measure food texture, and also considers techniques for measuring consumer perception of food texture (in addition to the sensory properties). Additionally, it amends omissions from the first edition such as dairy products; fish; bakery products; and, sugar confectionery, asproduct groups. All in all it is expanded and updated in its coverage of food texturology, as a coherent scientific discipline. Preface Contents Contributors Part I: Food Texture, Fundamentals Introduction to the Measurement of Sensory and Instrumental Food Texture 1 Introduction 2 Texturology 3 Food Texture and Product Quality 4 Food Texture Perception During Oral Processing 5 Comparison Between Instrumental and Sensory Measurement of Texture 5.1 Hardware 5.2 Temperature 5.3 Saliva 5.4 Speed of Test 5.5 Modality and Concurrency 6 Selected Terms Used in Instrumental and Sensory Texture 6.1 Hardness 6.2 Fracturability, Brittleness 6.3 Cohesiveness 6.4 Cohesiveness of Mass 6.5 Adhesiveness, Stickiness 6.6 Viscosity 6.7 Elasticity, Springiness, Resilience 6.8 Gumminess and Chewiness 6.9 Non-mechanical Texture Attributes 6.9.1 Chew Count 6.9.2 Denseness 6.9.3 Granularity 6.9.4 Conformation 6.9.5 Moistness 7 Conclusion References Food Structure as a Foundation for Food Texture 1 Introduction 2 Food Microstructure 2.1 Food Development Trends 2.2 Food Product Design 2.3 Food Building Blocks and Their Relevant Scale 3 Microscopy Techniques to Understand Food Structure 3.1 Process Miniaturisation Using Hot-Stage Polarised-Light Microscopy 3.2 Confocal Laser Scanning Microscopy (CLSM) to Visualise Food Microstructure 3.3 Electron Microscopy in Food Studies 3.4 X-Ray Micro-Computed Tomography (Micro-CT) to Quantify Food Microstructure 3.5 Super-Resolution Microscopy (SRM) in Food Materials 4 Microstructural Approach to Understand the Impact of Ingredient Reformulation on Food Texture 4.1 Soluble Fibre to Replace Sugar 4.2 Oleogels and Bigels as Fat Substituents 4.3 Alternative Proteins to Replace Gluten and Animal Proteins 5 Conclusions References Food Texture Diagrams and Maps 1 Introduction 2 Non-map Diagrams 2.1 Butchery Diagrams 2.2 Scales 2.2.1 Scale of Food Hardness 2.2.2 Textural Spectrum of Foods 3 Scientometric Maps 4 Ingredient Maps 4.1 Bakery Map 4.2 Moisture Map 5 State Diagrams as Texture Maps 5.1 Sucrose:Water State Diagram 5.2 Starch 5.2.1 Relatively Dilute Starch Systems 5.2.2 Relatively Concentrated Starch Systems 6 Rheology Texture Maps 6.1 Plastic–Elastic Map 6.2 Stress–Strain Diagrams as Maps 7 Sensory Texture Maps 7.1 A Sensory Exploration of the Stress–Strain Diagram 7.2 Vegetable Texture 7.3 Apple Texture 7.4 Fish Texture 8 Dimensions of Food Texture 9 Oral Processing 9.1 Viscosity and Oral Perception 9.2 The Breakdown Path 9.3 The Oral Trajectory 9.4 Eating and Swallowing Capability 10 Conclusions References Oral Physiology and Mastication 1 Physiology of Elements in the Oral Cavity 1.1 Teeth 1.2 Jaws and Temporomandibular Joints 1.3 Tongue 1.4 Salivary Glands and Saliva 1.5 Masticatory Muscles 1.6 Other Oral Elements 2 Control and Adaptation of Mastication 2.1 Mechanoreceptors and Proprioceptors 2.2 Neural Mechanisms 2.3 Innervation of Muscles Involved in Mastication and Associated Oral Functions 2.4 Jaw Reflexes 2.5 Bite Forces and Masticatory Forces 3 Oral Processing of Food 3.1 Principal Methods for Studying Food Oral Processing 3.1.1 Forces and Muscular Contraction Recordings 3.1.2 Methods for Mandibular Movement Recordings 3.1.3 Tongue Movements and Tongue–Palate Pressure Recordings 3.1.4 Saliva Sampling 3.1.5 Food Bolus Characterisation 3.1.6 In Vitro Simulation of Mastication 3.2 Influence of Oral Physiology on Food Oral Processing and Food Bolus Formation 3.2.1 Food Oral Processing 3.2.2 Food Bolus Characteristics 3.2.3 Role of Saliva 3.2.4 Role of the Tongue 3.2.5 Interindividual Variability in Food Oral Processing and Food Bolus Characteristics 3.2.6 Impact of Ageing on Food Oral Processing 3.2.7 Impact of Tooth Loss and Oral Deficiencies on Food Oral Processing and Food Bolus Characteristics 3.3 Influence of Food Characteristics on Food Oral Processing and on Food Bolus 3.3.1 Swallowing Threshold 3.4 Challenges and Perspectives in Food Oral Processing Research Area References Part II: Food Texture, Sensory and Human Interactions Psychophysics of Texture Perception 1 Introduction 2 Background and Milestones in Psychophysics 2.1 Weber’s Fraction (1830s) 2.2 Fechner’s Logarithmic Law (Around 1860) 2.3 Stevens’ Power Law (Around 1961) 2.4 Proposed Modified Stevens’ Law (2021) 2.5 A Consolidation of Fechner’s Logarithmic Law (2021) 3 Food Psycho-rheology 4 Importance of Texture Psychophysics in Food Science 4.1 Texture Psychophysics and Novel, Alternative, Healthy and Sustainable Foods 4.2 Texture Psychophysics, Quality Control and Marketing 4.3 Sensory Texture Claims Substantiation 4.4 Texture Psychophysics Across the Life Cycle 4.5 Texture Psychophysics in Health and Disease States 4.6 Psychophysics and Ingestive Behaviour 5 Texture Psychophysics of Food Systems 5.1 Texture Psychophysics of Liquid and Semi-Solid Foods 5.1.1 Thickness Perception and Viscosity 5.1.2 Grittiness and Smoothness Perception: Particle Size, Friction and Matrix Effects 5.1.3 Fat Perception and Greasiness Detection Thresholds 5.2 Texture Psychophysics of Solid Foods 5.2.1 Softness–Hardness Continuum 6 Food Texture Representation in the Brain 7 Challenges and Limitations for Food Texture Psychophysics 8 Concluding Remarks Refereces Sensory Scaling and Measuring Techniques 1 Introduction and Evolution 2 Methods for Sensory Description 3 Alternative Methods for Sensory Characterization 3.1 Attribute-Based Methods 3.1.1 Free-Choice Profiling 3.1.2 Flash Profiling 3.1.3 Check-All-That-Apply Questions 3.2 Temporal Methods 3.3 Holistic Methods 3.3.1 Sorting 3.3.2 Projective Mapping 3.4 Open-Ended Questions 4 Conclusions References Untitled The Meaning of Sensory and Consumer Terminology 1 Introduction 2 Analytical Sensory Terminology 3 Terminology of Consumers 3.1 Understanding Texture Perception from Consumer Terminology 4 Classification and Use of Texture Terms in Different Languages 5 Terms for Consumer Characterisation of Texture 6 Conclusions References Consumer Perception of Food Texture in Relation to Preferences and Food Intake 1 Food Texture and Its Implications for Consumer’s Perception 1.1 Oral Processing and Texture Perception 1.2 Texture and Consumers’ Preferences 1.3 Texture, Food Intake and Satiety Perception 1.3.1 Definition and Factors Influencing Satiation and Satiety 1.4 Individual Differences in Oral Processing and Texture Perception 2 Sensory and Consumer Measurements of Texture in Relation to Food Preferences and Satiation 2.1 Static and Dynamic Sensory Methods 2.2 Measurements of Satiety and Satiation 2.2.1 Actual Measures of Satiation and Satiety 2.2.2 Expectations Measurements 2.2.3 The Influence of Liking and Palatability in Food Intake 2.3 Understanding Individual Differences in Food Preferences, Satiety and Food Intake 2.3.1 PLS Path Modelling (PLS-PM) 2.3.2 SO-PLS Path Modelling (SO-PLS-PM) 3 Case Studies 3.1 Case Study 1: Understanding the Role of Dynamic Texture Perception in Consumers’ Expectations of Satiety and Satiation. A Case Study on Barley Bread 3.1.1 Background 3.1.2 Main Results: Sensory Drivers of Liking and Expectations of Satiety for Each Time Interval 3.1.3 Implications 3.2 Case Study 2: Identifying Temporal Drivers of Liking and Satiation Based on Temporal Sensory Descriptions and Consumer Ratings 3.2.1 Background 3.2.2 Main Results: Temporal Drivers of Expected Satiety and Liking 3.2.3 Implications 4 Closing Remarks and Future Perspectives References Part III: Food Texture, Instrumental Analysis Texture Analysers 1 What Is a Texture Analyser? 2 The Origin and Growth of Texture Analysers 3 Texture Analyser Construction 3.1 Key Components 3.1.1 Column 3.1.2 Instrument Arm 3.1.3 Test Aperture 3.1.4 Drive Mechanism 3.1.5 Displacement Measurement 3.1.6 Load Cell 3.1.7 Electronics 3.1.8 Safety Mechanisms 3.2 Calibration 3.2.1 Force Calibration 3.2.2 Force Verification 3.2.3 Zero Height 3.2.4 Unit Convention in the Food Industry 3.3 Frame Deflection 3.3.1 Frame Compliance Correction 3.4 Load Cells 3.4.1 Capacity 3.4.2 Accuracy and Precision 3.4.3 Format 3.4.4 Non-linearity 3.4.5 Hysteresis 3.4.6 Temperature Effects 3.4.7 Response Time 4 Software 4.1 Test Setup and Customisation 4.1.1 Environmental Temperature and Humidity 4.2 Analysis 4.3 Help 5 Suitability of Texture Analysers for Different Food Applications 5.1 Force 5.1.1 Force Sensitivity 5.2 Speed 5.3 Displacement 5.3.1 Displacement Sensitivity 5.4 Time 5.4.1 Time Sensitivity 5.5 Hold Control 6 Probes and Fixtures 7 The Future of Texture Analysers 7.1 Temperature and Humidity 7.2 Acoustic 7.3 Video 7.4 Extensometer 7.5 Powder Flow 7.6 Automation 7.7 Modernising Texture Analysis References Rheometry and Rheological Characterisation 1 Food Rheology History and Fields of Application 1.1 Historical Aspects of Food Rheology 1.2 Fields of Applications in Food Rheology 2 Rheometry Principles and Technologies 2.1 Principles of Rotational Rheometry 2.2 How Do Rheometers Work? 2.3 Measuring Geometries for Rotational Rheometers 2.3.1 Parallel Plate Geometries 2.3.2 Cone and Plate Geometries 2.3.3 Cup and Bob Geometries 3 Application Examples and Sample Handling 3.1 Yield Stress 3.2 Viscosity 3.3 Viscoelasticity 3.4 Texture, Tackiness and Mouthfeel 3.5 Sample Handling 4 Beyond Rotational Rheometry and Measurements References Tribometers for Studies of Oral Lubrication and Sensory Perception 1 Introduction 1.1 Tribology 1.2 Principles of Tribology 1.3 The Design and Operation Principle of a Tribometer 1.4 Experimental Techniques for Industrial Tribology Research 2 ‘Oral Tribology’ 3 Instruments for ‘Oral’ Tribology Studies 3.1 Friction Tester 3.2 Soft Texture Analyser Tribometer (STAT) 3.3 Optical Tribological Configuration (OTC) 3.4 Rheometer-Based Tribometer 3.4.1 Tribo-Rheometer 3.4.2 Tribo-Rheo Cell 3.4.3 Mounted Tribological Device 3.5 Mini-Traction Machine (MTM) 3.6 Other Tribometers 3.6.1 High Frequency Reciprocating Rig 3.6.2 Reciprocating Motion Sliding Tribometer 3.6.3 Tribolab 4 Applications of Tribology for Sensation Predictions During Oral Processing of Food 4.1 Creaminess 4.2 Astringency 5 Challenges and Future Developments 5.1 Tribopairs 5.1.1 Mode of Surface Movement 5.1.2 Morphological Dynamics of Human Tongue 5.1.3 Saliva 6 Conclusions References New In Vitro and In Situ Instrumental Approaches for Food Texture Research 1 Introduction 2 Instrumental Approaches in Food Texture Research 2.1 Classical Approaches to Food Texture Research 2.2 Novel Approaches to Food Texture Research 3 Modifications to the Texture Analyzer in Food Texture Research 4 Ultrasound in Food Texture Research: Tongue-Food Interaction 4.1 Tongue-Food Interaction 4.1.1 Case I: Impact of Surface Roughness and Lubrication 4.1.2 Case II: Impact of Tongue Roughness During Compression 4.1.3 Case III: Impact of Deformable Tongue Roughness and Rigidity During Compression with Food Gels 4.1.4 Case IV: Behavior of Stacked Gels Composition and Arrangement During Compression on the Deformable Artificial Tongue 4.2 Ultrasound Imaging 4.2.1 Ultrasound Imaging for Investigating Semi-Solid Food 4.2.2 Ultrasound for Investigating Tongue Movements and Food Bolus 4.2.3 Investigating Food Oral Processing by Ultrasound Imaging 5 Modified and Custom-Made Oral Tribometers 5.1 Overview of Tribometers Aimed at Oral Tribology Investigations 5.2 Custom-Made Oral Tribometer Investigations 5.3 Variations in the Food Model, Operational Parameters, and Artificial Tongues 6 Oral Masticators 6.1 Overview of Oral Masticators 6.1.1 Oral Masticator for Investigating In Vitro Chewing of Cereal Bars 6.1.2 Comparison of Food Particle Size Produced by Oral Masticator and Human Participants 6.1.3 Oral Masticator Deployed for Food Texture Investigations 7 Conclusions and Future Trends References Part IV: Food Texture, Food Products Texture of Vegetables and Fruit 1 Introduction 2 Organs, Tissues, and Texture Perceptions 3 Components of Texture 3.1 Water 3.2 Storage Carbohydrates 3.3 Cell Walls 3.3.1 Polysaccharides 3.3.1.1 Pectins 3.3.1.2 Hemicelluloses 3.3.1.3 Cellulose 3.3.2 Pectin and V&F Texture 3.3.2.1 Role of Charges and Apoplast Physicochemical Conditions 3.3.2.2 Role of Substitutions and Side-Chains 3.3.3 Hemicelluloses and Cellulose Role in V&F Texture 3.3.4 Proteins 3.3.4.1 Extensin 3.3.4.2 Arabinogalactan Proteins (AGP) 3.3.5 Lignin, Cutin, Suberin 3.3.5.1 Lignin 3.3.5.2 Cutin and Suberin 3.3.6 Cell Wall, a Dynamical Assembly 4 Assessment of Vegetable and Fruit Texture 4.1 Optical Non-destructive Texture Assessment 4.2 Mechanical- and Acoustical-Based Non-destructive Texture Assessment 4.3 Limits and Perspectives in Non-destructive Texture Assessment 5 Impact of Processing on the Texture of V&F 6 Conclusions and Perspectives References Texture of Bakery Products 1 Introduction to Bakery Products Key Ingredients and Structure of This Chapter 1.1 Flour – Types and Suitability for Different Products 1.1.1 Flour Proteins 1.1.2 Starch 1.2 Sugar 1.3 Fat 2 Bread 2.1 Perception and Measurement of Bread Texture 2.2 Factors Determining Bread Texture 3 Pastry 3.1 Shortcrust Pastry 3.2 Puff Pastry 3.2.1 The Lamination Process 3.3 Phyllo/Filo Pastry 3.4 Choux Pastry 3.5 Pastry Characterisation and Measurement Techniques 3.6 Factors Determining Pastry Texture 4 Biscuits 4.1 Perception and Measurement of Biscuit Texture 4.2 Factors Determining Biscuit Texture 5 Cake 5.1 Mixing 5.1.1 Single-Stage Mixing 5.1.2 Multistage Mixing 5.2 Factors Determining Cake Texture 5.3 Cake Characterisation and Measurement Techniques 6 Summary References Meat and Reformed Meat Products 1 Muscle Structure and Composition 1.1 Muscle Structure 1.2 Muscle Contraction 2 Rigor Mortis 2.1 Abnormal Rigor Mortis 3 Influence of Live Animal Factors 3.1 Effects of Breed and Genetics 3.2 Effects of Fatness 3.3 Influence of Sex 3.4 Effect of Animal Age and the Role of Connective Tissue 3.5 Influence of Growth Rate and Plane of Nutrition 3.6 Stress Conditions and Pre-slaughter Handling 4 Effects of Stunning and Slaughter 5 Effects of Post-slaughter Treatments 5.1 Chilling 5.2 Electrical Stimulation 5.3 Carcase Suspension Methods 5.4 Ageing 6 Effects of Processing 6.1 Hot-Boning 6.2 Use of Proteolytic Enzymes 6.3 High-Pressure Treatment 6.4 Curing 7 Reformed Meat Products 7.1 The Texture of Coarse-Ground Meat Products 7.1.1 Effect of Processing Conditions on the Texture of Coarse-Ground Meat Products 7.1.2 Effect of Composition on the Texture of Coarse-Ground Meat Products 7.2 Structure of Finely Comminuted Meat Products 7.2.1 Effect of Processing Conditions on the Texture of Finely Comminuted Meat Products 7.2.2 Effect of Composition on the Texture of Finely Comminuted Meat Products 8 Measurement of Texture in Meat and Meat Products 8.1 Sensory Methods 8.2 Instrumental Assessment of Meat Cuts 8.3 Assessment Methods Used for the Textural Properties of Meat Products 9 Summary References Texture of Fish and Fish Products 1 Introduction 2 Key Detection Techniques for Texture of Fish and Fish Products 2.1 Sensory Evaluation of Texture 2.2 Instrumental Evaluation of Texture 3 Textural Properties of Raw Fish 3.1 Factors Influencing the Textural Properties of Raw Fish 3.1.1 Growth Environment 3.1.2 pH 3.1.3 Storage Temperature 3.1.4 Life Cycle 3.1.5 Anatomic Position 3.1.6 Diet 3.1.7 Slaughter Methods 4 Texture of Fish Products 4.1 Surimi and Surimi Products 4.1.1 The Formation Mechanism of Surimi Products 4.1.2 Factors Influencing the Textural Properties of Surimi Products 4.1.2.1 Raw Fish Quality 4.1.2.2 Processing Methods 4.1.2.3 Exogenous Additives 4.1.3 Methods to Improve the Textural Properties of Surimi Products 4.1.3.1 Exogenous Additives 4.1.3.2 Improving Processing Methods 4.2 Dried Fish Products 4.2.1 Methods to Improve the Textural Properties of Dried Fish 4.2.2 Freeze Drying 4.2.3 Microwave Drying 4.2.4 Infrared Drying 4.2.5 Multistage Drying 4.3 Smoked Fish Products 4.3.1 Factors Influencing the Textural Properties of Smoked Fish 4.3.1.1 Raw Materials 4.3.1.2 Pretreatment Methods 4.3.1.3 Smoking Methods 4.3.2 Methods to Improve the Textural Properties of Smoked Fish 4.4 Fermented Fish Products 4.4.1 Factors Influencing Textural Properties of Fermented Fish Products 4.5 Canned Fish Products 4.6 Other Products 4.6.1 Easy-to-Eat Fish Products 4.6.2 Fish Snack Products 5 Conclusion References Texture of Dairy Products 1 Introduction 1.1 Introduction to Rheological Properties of Milk 1.2 Milk Viscosity 1.3 Newtonian and Non-Newtonian Fluids 1.4 Rheology of Creams and Other High Fat Products 1.5 Viscoelasticity in Dairy Products 2 Dairy Products 2.1 Cream Viscosity – Practical Aspects 2.2 Butter and Spreads 2.3 Dairy Foams 2.4 Concentrated Milk 2.5 Milk Fermentation 2.5.1 Yoghurt 2.5.2 Cheese Products 2.5.2.1 Introduction 2.5.2.2 Cheese Grading and Cheese Rheology 2.6 Milk Powders 2.6.1 Introduction 2.6.2 Powder Compression and Selection of the Best Powder 2.7 Products Containing Dairy Ingredients 2.7.1 Freezing and Frozen Desserts 2.7.2 Chocolate Rheology 3 Conclusions References Candy Texture (Sugar Confectionery) 1 Introduction 1.1 Overview 1.2 Texture 1.2.1 Sensory Assessment 1.2.2 Texture Analyzer 1.2.3 Other Instruments 2 Hard Candy 2.1 Ingredients and Manufacturing 2.2 Structure 2.3 Rheology and Texture 3 Fondants and Creams 3.1 Ingredients and Manufacturing 3.2 Structure 3.3 Rheology and Texture 4 Gummies and Jellies 4.1 Ingredients and Manufacturing 4.2 Structure 4.2.1 Gelatin 4.2.2 Starch 4.2.3 Pectin 4.2.4 Mixed Hydrocolloids 4.3 Rheology and Texture 5 Licorice 5.1 Ingredients and Manufacturing 5.2 Structure 5.3 Rheology and Texture 6 Marshmallow 6.1 Ingredients and Manufacturing 6.2 Structure 6.3 Rheology and Texture 7 Chewy Candies 7.1 Ingredients and Manufacturing 7.2 Structure 7.3 Rheology and Texture 8 Caramel, Fudge, and Toffee 8.1 Ingredients and Manufacturing 8.1.1 Caramel 8.1.2 Fudge 8.1.3 Toffee 8.2 Structure 8.3 Rheology and Texture 9 Tablets and Lozenges 9.1 Ingredients and Manufacturing 9.2 Structure 9.3 Rheology and Texture 10 Gum 10.1 Ingredients and Manufacturing 10.2 Structure 10.3 Rheology and Texture 11 Sugar Panned Candies 11.1 Ingredients and Manufacturing 11.2 Structure 11.2.1 Soft Panning 11.2.2 Hard Panning 11.3 Rheology and Texture 12 Chocolate 12.1 Ingredients and Manufacturing 12.2 Structure 12.3 Rheology and Texture 12.3.1 Liquid Chocolate/Rheology 12.3.2 Solid Chocolate/Mechanical 13 Summary References Starch, Modified Starch, and Extruded Foods 1 Introduction 2 Starch Granules and Composition 2.1 Composition of Starch Granules 2.2 Molecular Structure of Amylose and Amylopectin 3 Morphological Properties of Starch Granules 3.1 Light Microscopy 3.2 Polarized Light Microscopy 3.3 Scanning Electron Microscopy (SEM) 3.4 Confocal Scanning Laser Microscopy 3.5 Atomic Force Microscopy (AFM) 4 Physiochemical Changes of Starch During Heating and Cooling 4.1 Starch Gelatinization 4.2 Starch Pasting 4.3 Starch Gelation 4.4 Starch Retrogradation 5 Properties of Starches from Different Botanical Origins 5.1 Morphological Properties 5.2 Composition, Swelling, and Solubility 5.3 Gelatinization Properties 5.4 Retrogradation and Textural Properties 6 Limitations of Native Starch and the Case for Starch Modification 7 Physical Modification of Starch 7.1 Applications of Physically Modified Starches in the Food Industry 8 Chemical Modification of Starch 8.1 Acid/Alkali Hydrolysis 8.2 Oxidation 8.3 Etherification 8.4 Esterification 8.5 Cross-Linking 8.6 Dual Modification 9 Enzymatic Modification of Starch 9.1 Enzymes Used for Modification 9.1.1 Amylase 9.1.2 Debranching Enzymes 9.1.3 Starch Glycosyltransferase 9.2 Applications of Enzymatic Modified Starch in the Food Industry 10 Common Techniques to Study the Physicochemical Properties of Starch 10.1 Differential Scanning Calorimetry (DSC) 10.2 Texture Analysis 10.3 Rapid Visco Analyzer (RVA) 11 Extrusion Cooking of Starch 11.1 Transformation of Starch During Extrusion 11.2 Parameters Affecting the Textural Properties of the Starch-Based Extrudates 12 Application of Extrusion for Production of Modified Starch 12.1 Physical Modification 12.2 Chemical Modification 12.3 Dextrinization 13 Summary References Hydrocolloids as Texture Modifiers 1 Introduction 1.1 Mechanisms of Texture Formation 1.1.1 Gelation 1.1.2 Viscosity 1.1.3 Emulsification 2 Hydrocolloid Structure and Functionality 3 Starch 4 Gelatin 5 Microbial Polysaccharides (Xanthan, Gellan) 6 Cellulose Derivatives 7 Galactomannans 8 Seaweed Polysaccharides (Carrageenan, Alginates, Agar) 9 Pectin 10 Gum Arabic 11 Concluding Remarks References Textural Aspects of Special Food for Dysphagia Patients 1 Introduction 2 Dysphagia 3 Diet 3.1 Foods and Drinks Classification Used in Dysphagia Management 3.2 Testing Methods 3.3 Thickened Fluids 3.3.1 Level 0 – Thin 3.3.2 Level 1 – Slightly Thick 3.3.3 Level 2 – Mildly Thick 3.3.4 Level 3 – Moderately Thick 3.3.5 Level 4 – Extremely Thick 3.4 Texture Modified Foods 3.4.1 Level 7 – Regular and Easy to Chew 3.4.2 Level 6 – Soft and Bite-Sized 3.4.3 Level 5 – Minced and Moist 3.4.4 Level 4 – Pureed 3.4.5 Level 3 – Liquidized 3.5 Instrumental Assessment of IDDSI Food and Drinks Classification 4 Summary References Index