Hydrocolloids
Pages 27-41
DOI: https://doi.org/10.1094/1891127381.003
ISBN: 1-891127-38-1
Abstract
Topics Covered
- Hydrocolloid Dispersion and Hydration
- Thickening Agents Versus Gelling Agents
- Gelling Agents
- Thickening Agents
- Importance of the Uniformity of Substitution
- Compatibiltiy of Hydrocolloid Combinations
- Relative Cost of Hydrocolloids
Introduction to Chapter
Hydrocolloids serve two basic functions in food systems: they stabilize the product and they affect the texture of the product.
In this handbook, to “stabilize” a food product refers to the prevention of physical change in the product resulting 1) from separation of the food product's components over time (e.g., the settling of cocoa particles in chocolate milk or the rising of oil droplets in a salad dressing) and 2) from processing and handling conditions, such as high temperatures (e.g., the melting and running of a bakery filling subjected to oven heat). “Texture” refers to that of the finished food product. The hydrocolloid could be providing extra body and mouthfeel to a beverage or giving a gel structure to a milk-based dessert pudding.
Some of the more common functions hydrocolloids perform in food systems are shown in Table 3-1. Note that they can be classified as stabilizing, affecting texture, or both.
Other functions of food gums are fat replacement or reduction and “fat holdout.” When fat or oil is removed from a formula, it has to be replaced with something, and that something is usually water. The texture of the water must be altered to better imitate the texture contributed by the missing fat or oil. This can be done with food gums. Fat holdout generally refers to the reduction in the amount of oil or fat absorbed by foods that are deep fat fried, such as french fries or battered and breaded chicken or fish. If a film of food gum is applied around these items prior to deep fat frying, the amount of oil or fat absorbed is reduced. Oil absorption can generally be cut in half before a noticeable change in texture or flavor occurs.
