Mangrove Jack's Carrageenan is a clarifier and is used to clear protein during the boil when mash brewing.
Irish Moss and Eucheuma are two of the many seaweed sources of carrageenans. Follow your beer recipe guidance for use.
Contains: Semi-refined carrageenan (derived from red seaweed Eucheuma).
Further Reading on Carrageenans and Irish Moss:
Irish moss and formulated carrageenans are sometimes used to enhance the effectiveness of fining (clarifying) beer with isinglass. In this situation the carrageenans are known as “auxiliary finings.” Because the carrageenans have a similar electrical charge to that of the yeast cells they assist in creating the yeast-isinglass matrix and facilitate a more effective sedimentation process.
Ryder, David S., and Joseph Power. “Miscellaneous ingredients in aid of process.” In Handbook of brewing, eds. F. G. Priest and G. G. Stewart, 354–355. New York: Taylor and Francis, 2006.
George Philliskirk Craft Beer and Brewing Magazine