Food Structures, Digestion and Health

Mike Boland, Matt Golding, Harjinder Singh

• Publisher: Academic Press
• Year: 2014
• Print ISBN:
  9780124046108
• eBook ISBN:
  9780124046856
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

This selection of key presentations from the Food Structures, Digestion and Health conference is devoted to the unique and challenging interface between food science and nutrition, and brings together scientists across several disciplines to address cutting-edge research issues. Topics include modeling of the gastrointestinal tract, effect of structures on digestion, and design for healthy foods. New knowledge in this area is vital to enable the international food industry to design of a new generation of foods with enhanced health and sensory attributes. The multidisciplinary approach includes research findings by internationally renowned scientists, and presents new research findings important and pertinent to professionals in both the food science and nutrition fields. - Describes the science underpinning typical food structures providing guidance on food structure in different conditions - Includes novel approaches to the design of healthy foods using real-world examples of applied research and design written by top leaders in the area - Describes and validates model systems for understanding digestion and predicting digestion kinetics

Section 1

Understanding Food Structures in Natural and Processed Foods and their Behavior During Physiological Processing

Outline

Chapter 1. Understanding Food Structures

Chapter 2. Processing of Food Structures in the Gastrointestinal Tract and Physiological Responses

Chapter 3. The Basis of Structure in Dairy-Based Foods

Chapter 4. The Milk Fat Globule Membrane

Chapter 1

Understanding Food Structures

The Colloid Science Approach

Eric Dickinson School of Food Science and Nutrition, University of Leeds, Leeds, UK

Abstract

Food is a highly complex form of soft condensed matter. This complexity arises from the biological diversity of raw materials, the many ingredients that are typically combined together, and, most especially, the subtle changes in molecular interactions and microstructure induced by food processing and storage. In order to rationalize this complexity, it is convenient to assume the key attributes of texture, rheology, and physical stability are determined by the spatial organization of a small number of generic structural entities—biopolymers, aggregates, particles, networks, droplets, and bubbles. This chapter describes recent advances in this field of food colloid science with particular reference to various kinds of emulsion-based systems. Attention is directed towards the crucial role of the macromolecular ingredients, proteins, and polysaccharides in controlling the formation and stabilization of these emulsion structures. The underlying objective is to provide fundamental insight into methods for formulating food products with enhanced health-related attributes.

Keywords

structure; colloids; nanoscience; emulsions; particles; encapsulation; gelation; aeration; rheology; digestion

Contents

Introduction 3

On Colloid Terminology in the Age of “Nano” 8

Essential Principles of Structure Formation and Stabilization 11

Some Specific Types of Food Emulsion Structuring 20

Multilayer Emulsions 20

Pickering Emulsions 23

Double Emulsions 26

Emulsion Gels 29

Aerated Emulsions 32

Relationship of Structure to Sensory Perception 34

Relationship of Structure to Digestion and Health 36

References 41

Introduction

As diet-related health problems continue to increase globally, there is recognition within the research community of the need for more detailed knowledge of the behavior of foods as they are processed within the human digestive system. Individual foods differ considerably in their nutrient composition and also in terms of the matrix materials within which the nutrients are embedded. During eating, the breakdown property of the food matrix is a major controlling factor for the perception of texture and flavor in the mouth. After swallowing, the processing of the disrupted food matrix in the gastrointestinal tract influences the perception of postprandial satiety and bioavailability of nutrients. It seems reasonable to assert that, in order for food technologists to continue to be able to develop nutritious foods from healthier combinations of ingredients, there is an underlying requirement to understand more fully the changing structural behavior of foods during eating and digestion.

The challenges posed by the complex dietary health issues are made more extreme by the potentially conflicting demands of consumers that food should be simultaneously tasty, wholesome, healthy, and cheap. According to the food industry, it is generally necessary for processed foods to contain high levels of fat, salt, and sugar in order to meet existing consumer expectations with respect to flavor and texture. Nevertheless, well-founded concern over the adverse health implications of the overconsumption of certain types of lipids has led the industry to develop alternative “low-fat” and “reduced fat” food products. In addition, the identification and widespread public recognition of the health-promoting properties of certain bioactive compounds has generated commercial opportunities for marketing high-value specialist products containing encapsulated bioactives (nutraceuticals). On the downside, however, many of the notionally healthier products containing less fat (or salt or sugar) are often perceived by consumers as being of inferior organoleptic quality. This is because the methods used to modify food composition have effects on other essential food characteristics such as taste, appearance, and texture (Velikov and Pelan, 2008). Furthermore, many of the specialist products containing added health-beneficial nutraceuticals may be regarded as expensive “niche” products of significant benefit only to a small fraction of consumers with specific recognized medical conditions. Overshadowing these commercial trends is one further problem: the available evidence suggests that a large proportion of the consumers in Western societies are not easily persuaded to compromise their eating pleasure, or to increase their grocery shopping expenditure, simply for the sake of some promised long-term health benefits. Hence, the successes of governments and industry in modifying eating habits for the sake of improving long-term well-being remain disappointingly limited.

Against this challenging background, the food technologist aims to develop cheap healthier alternatives to existing processed foods without diminishing the consumer’s organoleptic experience. Understanding how this can be done requires detailed insight into the relationship between the composition and processing of the food and its multifaceted properties—nutritional, sensory, and physicochemical. These days it is an implicit belief of most food researchers that one important piece of information, the food structure, is a prerequisite to determining how the ingredient composition and processing conditions are mechanistically related to the product properties. There was perhaps once a time when the subject of food structure was solely the specialist domain of the food microscopist, but that time has long since gone. Structural information is now an essential requirement of all those concerned with the control of food ingredient functionality during food manufacture, storage, and digestion.

So what is meant by “food structure”? The answer depends to some extent on the perspective of the observer—as physicist, chemist, biologist, or engineer. The ...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Preface
• Section 1. Understanding Food Structures in Natural and Processed Foods and their Behavior During Physiological Processing
• Section 2. Impact of Food Structures and Matrices On Nutrient Uptake and Bioavailability
• Section 3. Modelling the Gastrointestinal Tract
• Section 4. Food Developments to Meet the Modern Challenges of Human Health
• Index