Carrageenans are gel-forming hydrocolloids extracted from the cell walls of marine red algae, such as Eucheuma, Chondrus, Gigartina, Hypnea. Carrageenan is a hydrophilic colloid. The chemical structure of carrageenan is calcium, potassium, sodium, ammonium salts of polysaccharide sulfate composed of galactose and dehydrated galactose.