Hydrocolloids are polysaccharides or proteins that are hydrophilic (water-loving) and form gels, thick suspensions, or thickeners when dispersed in water. They are widely used in the food industry as stabilizers, thickeners, and gelling agents to control texture, viscosity, and stability of food systems.
Hydrocolloids are made from various natural sources such as seaweeds, plants, animals, and microorganisms. Examples of plant-based hydrocolloids are xanthan gum, carrageenan, guar gum, and pectin. Examples of animal-based hydrocolloids are gelatine and casein. Microbial hydrocolloids include xanthan gum and gellan gum.
Starch is considered as a hydrocolloid in food systems. Hydrocolloids made from starch are usually obtained by chemical or enzymatic hydrolysis of native starch, which breaks down the starch molecule into smaller, more water-soluble fragments. These fragments can form gel-like structures in water, and can be used to thicken, stabilize, or emulsify food products. Some examples of hydrocolloids made from starch include starch hydrolysates, maltodextrins, and cyclodextrins.
Modified and native starches represent more than 85% of all hydrocolloids used in food systems (Wanous, 2004)
Some common hydrocolloids used in food systems are:
- Gum arabic
- Carrageenan
- Guar gum
- Xanthan gum
- Pectin
- Gelatin
- Agar
- Alginate
- Chitosan
- Locust bean gum.