Carrageenan, also known as carrageenan and carrageenan. Carrageenan is a hydrophilic colloid extracted from some red algae seaweed. Its chemical structure is calcium, potassium, sodium and ammonium salts of polysaccharide sulfate composed of galactose and dehydrated galactose. Due to the different binding forms of sulfate, it can be divided into K-type (Kappa), I-type (Iota) and L-type (Lambda). The utilization of carrageenan, the raw material for making carrageenan, originated hundreds of years ago. A kind of seaweed, commonly known as Irish Moss, is now called Chondrus crispus, which is often collected by local residents and boiled in milk with sugar, cooled and solidified before eating. /kloc-At the beginning of the 8th century, the Irish made this seaweed into powder and introduced it to the United States. Later, some companies began commercial production and began to sell it under the name of sea moss farina, which was widely used in milk and various foods. 19th century, the United States began to refine carrageenan industrially, and it was not until119th century that the carrageenan industry really developed in the United States. China began to produce carrageenan in Hainan Island in 1973. The key depends on its composition and origin. From the data found, it can be eaten.