The ‘original’ carrageenan was extracted from Chondrus Crispus,a red seaweed found in the north Atlantic. Another name for this seaweed is ‘Irish moss’; a name still used in the brewing industry. Chondrus crispus actually contains a mix of carrageenan types, the predominant ones being kappa and lambda. Today Chondrus Crispus is not one of the major sources of carrageenan in world terms. Chondrus Crispus is wild harvested and some is farmed for use in the culinary market.
Today, most carrageenan is extracted from the tropical red species of Kappaphycus and Eucheuma. Kappaphycus is commercially known as “cottonii”. It is primarily grown in Southeast Asia but also elsewhere around the tropics. Eucheuma, commercially known as “spinosum” is mostly cultivated in Africa but also in SE Asia. These species are relatively pure in the carrageenan type they contain. Cottonii is predominantly kappa carrageenan and Spinosum is largely iota carrageenan. This allows greater flexibility in formulation because you are not restricted to the ratios of kappa and iota that happen to occur in the native weedstock.
Gigartina skottsbergii and Sarcothalia crispata are also key species used in the extraction of carrageenan, both are harvested off the coast of Chile and other South American countries. Similar species, Mazzaella, Chondracanthus are harvested in smaller amounts. Unlike the seaweeds previously mentioned, the Gigartinaceae type weeds have the various carrageenan types actually mixed up along the same polymer chain in a ‘hybrid’ type of polymer. They are often referred to as “Hybrid” types and contain mixtures of kappa, iota and lambda carrageenan. These carrageenans are often preferred in some dairy applications.
Hypnea and Furcellaria are other types of carrageenan bearing seaweeds that are occasionally used. Furcellaria is a North Atlantic species and there is a small industry in Estonia. Furcellaria yields a kappa type carrageenan that was historically referred to as Danish agar. It can be used in much the same way as kappa carrageenan.
Further information on carrageenan structure, production, synergy and protein interaction can be accessed using the arrows in the Further Reading box below.