Emerging Natural Hydrocolloids

Rheology and Functions

Seyed M.A. Razavi

• Publisher: Wiley
• Year: 2019
• Print ISBN:
  9781119418665
• Edition: 1
• eBook ISBN:
  9781119418542
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

The first guide devoted to the functions, structures, and applications of natural hydrocolloids

In today's health-conscious climate, the demand for natural food products is growing all the time. Natural hydrocolloids, therefore, have never been more popular. With their thickening, stabilizing, gelling, fat replacing, and binding qualities, these naturally occurring, plant-based polymers can fulfil many of the same functions as commercial ingredients like xanthan, guar, gum Arabic, pectin, and starch. Moreover, certain health benefits have been linked with their often biological active compounds and high-fiber compositions, including potential prebiotic effects and the reduction of blood cholesterol levels.

Application of these novel hydrocolloids is, however, still underexplored. Emerging Natural Hydrocolloids aims to remedy this by providing a thorough overview of their structure–function relationships, rheological aspects, and potential utility in mainly the food and pharmaceutical industries. This accessible, quick-reference guide features:  

• A comprehensive and up-to-date survey of the most significant research currently available on natural hydrocolloids
• Examinations of the major functions and rheological aspects of novel hydrocolloids
• Information on the potential applications of biopolymers within both foods and pharmaceutical systems
• Collaborations from an international team of food scientists

Emerging Natural Hydrocolloids: Rheology and Functions offers scientists, engineers, technologists, and researchers alike a unique and in-depth account of the uncharted world of novel hydrocolloids, their uses, properties, and potential benefits.

1
Introduction to Emerging Natural Hydrocolloids

Seyed M.A. Razavi

Food Hydrocolloids Research Center, Department of Food Science and Technology, Ferdowsi University of Mashhad, PO Box: 91775‐1163, Mashhad, Iran

1.1 Introduction

Hydrocolloids, also known as gums, are a diverse group of long‐chain and hydrophilic polymers with high molecular weight which are readily dispersive, fully or partially soluble, and prone to swell in water, thus producing colloidal systems of different structures. Therefore, a hydrocolloid is a highly water‐soluble (or water‐dispersible) material that readily dissolves (or disperses) to form highly hydrated entities of colloidal dimensions (1–1000 nm) [1,2]. Hydrocolloids generally produce a dispersion, which is intermediate between a true solution and a suspension, and exhibit the properties of a colloid [3]. Each dissolved polymer molecule of a hydrocolloid ingredient is deemed to interact strongly via hydrogen bonding with its surrounding water molecules as well as with any neighboring hydrocolloid molecules. Due to the tendency of these large hydrophilic macromolecules to overlap and join together into entangled networks and macroscopic gels, most hydrocolloids have the capability to function as viscosity modifiers and thickeners in aqueous media at relatively low concentrations [4]. The presence of many hydroxyl groups in their structures conspicuously increases the affinity for binding water, rendering them hydrophilic. At sufficiently high concentrations, the hydrocolloids become entangled with each other, forming loose networks (gel) that change their rheological properties [5].

The term food hydrocolloid includes all the polysaccharides and proteins that are widely used in a variety of food processing sectors to control and regulate such a colloidal state. Food hydrocolloids are from various natural sources: agar and carrageenan are from seaweeds, guar gum and locust bean gum from plant seeds, pectin from citrus or apple peels, xanthan gum and gellan gum from microorganisms, and chitin and chitosan from animals [1]. Food hydrocolloids exhibit multiple functions in foods, including thickening, gelling, water holding, dispersing, stabilizing, film forming, and foaming, and have been used as a texture modifier in almost every kind of food product. Because of their interesting properties, food hydrocolloids are widely used as food additives to obtain particular functional properties [3]. In fact, food hydrocolloids are important parts of our daily diet in food systems such as yogurt, ice cream, cheese, mayonnaise and salad dressing, dessert jellies, bakery products, and so on [ 2,6]. The food industry especially has been using a large number of hydrocolloids in recent years as ingredients. Although they are often applied at low concentration (less than 1% of the final product), they significantly influence the textural, rheological, and sensory properties of the final products. These substances are best known as powerful thickeners but perform an extraordinary number of other functions essential to food quality. They impart food texture and structure, and they play a role in flavor release, appearance, and shelf stability [7,8]. They are actually not emulsifiers, because they lack the characteristic lipophilic and hydrophilic linkage in the molecular structure [9]. However, they can stabilize emulsions by increasing the viscosity of the continuous phase or by interaction with surface‐active substances. In recent years, food hydrocolloids have been recognized as healthy sources of fiber as well [10].

In general, hydrocolloids are natural‐origin biopolymers, but this does not mean that one cannot produce hydrocolloids through synthetic means. All kinds of hydrocolloids can be obtained from both renewable and non‐renewable resources. For many reasons, preference is being given to the renewable hydrocolloids. Due to the recent trends in the demand for all‐natural products by consumers, the aim is to replace the existing non‐renewable and synthetic hydrocolloids by renewable ones for different applications in industry, so we need to find novel natural hydrocolloids to provide certain unique features for the purpose. In order to introduce the novel hydrocolloids' potential and applicability in industries, it is necessary to explore the emerging natural hydrocolloids with the desired properties. In this chapter, some aspects of the hydrocolloids including hydrocolloid classification and functions are highlighted. In addition, a brief review of the chapters is presented at the end of this chapter.

1.2 World Market of Hydrocolloids

The global hydrocolloids market has been growing tremendously due to the increasing demand for healthy and natural products by health‐...

Table of contents

• Cover
• Table of Contents
• About the Editor
• List of Contributors
• Preface
• 1 Introduction to Emerging Natural Hydrocolloids
• 2 Dilute Solution Properties of Emerging Hydrocolloids
• 3 Steady Shear Rheological Properties of Emerging Hydrocolloids
• 4 Transient and Dynamic Rheological Properties of Emerging Hydrocolloids
• 5 Hydrocolloids Interaction Elaboration Based on Rheological Properties
• 6 Sage (Salvia macrosiphon) Seed Gum
• 7 Balangu (Lallemantia royleana) Seed Gum
• 8 Qodume Shirazi (Alyssum homolocarpum) Seed Gum
• 9 Espina Corona (Gleditsia amorphoides) Seed Gum
• 10 Qodume Shahri (Lepidium perfoliatum) Seed Gum
• 11 Persian Gum (Amygdalus scoparia Spach)
• 12 Gum Tragacanth (Astragalus gummifer Labillardiere)
• 13 Cashew Tree (Anarcadium occidentale L.) Exudate Gum
• 14 Brea Tree (Cercidium praecox) Exudate Gum
• 15 Chubak (Acanthophyllum glandulosum) Root Gum
• 16 Marshmallow (Althaea officinalis) Flower Gum
• 17 Opuntia ficus‐indica Mucilage
• 18 Emerging Technologies for Isolation of Natural Hydrocolloids from Mucilaginous Seeds
• 19 Purification and Fractionation of Novel Natural Hydrocolloids
• 20 Improving Texture of Foods using Emerging Hydrocolloids
• 21 New Hydrocolloids in Ice Cream
• 22 Novel Hydrocolloids for Future Progress in Nanotechnology
• 23 Edible/Biodegradable Films and Coatings from Natural Hydrocolloids
• 24 Health Aspects of Novel Hydrocolloids
• Index
• End User License Agreement