Gelling agents are food additives used to thicken and stabilize various foods, like jellies, desserts and candies, to provide the foods with texture through a gel formation.
Typical gelling agents include natural gum, starches, pectin, agar ,gelatin and gellan gum.Often they are based on polysaccharides or proteins.some stabilizers and thickening agents are gelling agents too.
Among all of them,we would like to pay attention to gellan gum,the most expensive and effective one.
Gellan gum is a water-soluble anionic polysaccharide produced by the bacterium Sphingomonas elodea (formerly Pseudomonas elodea).As a food additive, gellan gum was first approved for food use in Japan (1988). Gellan gum has subsequently been approved for food, non-food, cosmetic and pharmaceutical uses by many other countries such as US, Canada, China, Korea and the European Union etc.
It is widely used as a thickener, emulsifier, and stabilizer. It has E number E418.Pure gellan gum is one of the most expensive hydrocolloids. Its cost in use, however, is competitive with the other much lower priced hydrocolloids.
Gellan gum, is often used as a gelling agent, alternative to agar, in microbiological culture. With heat resistance of 120°C . Gellan Gum was identified to be an especially useful and effective gelling agent in culturing thermophilic microorganisms. One needs only approximately half the amount of gellan gum as agar to get an equivalent gel strength, though the exact texture and quality depends on the concentration of the divalent cations present. Gellan gum is also used as gelling agent in plant cell culture on Petri dishes, as it provides a very clear gel, facilitating light microscopical analyses of the cells and tissues.
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