Carrageenophytes are marine plants commonly known as red seaweeds (Rhodophyceae) that contain carrageenan, a polysaccharide used as a hydrocolloid for the manufacture of many food, pharmaceutical and industrial products. Carrageenan constitutes the third most important hydrocolloid in the world after starch and gelatin. The world market for carrageenan was valued at $305 million in 1998. Besides carrageenan, the other hydrocolloids extracted from seaweeds are agar and alginates from agarophytes and brown seaweeds, respectively. The Philippines is the world’s largest producerofcarrageenophytes. From virtually zero production in the 1960s, the country has provided up to 80% of global supply of carrageenan through aquaculture in the 1990s.