Mixture of polysaccharides, similar to agar-agar, which is obtained by extraction with hot water from certain red algae, e.g. Chondrus crispus of the Irish moss. Carrageenan essentially consists of carragenin, a branched-chain polysaccharide.
Carrageenan is mainly used in the food industry as a gelling, emulsifying and stabilizing agent.
Cosmetically, the sodium and potassium salts are used under the INCI designations sodium/potassium carrageenan salt.