Irish moss is not actually a "moss" but a type of seaweed that has been used for centuries in Ireland as a healing sea vegetable, prepared in soups and puddings. It is traditionally brewed as a broth to release its beneficial nutrients. It was a staple during the Irish famine of 1845-1852. It can also be soaked and blended as irish moss gel and added to various foods and drinks as a nutritive thickening agent. It is a very mucilaginous seaweed which wouldn't normally be eaten like other varieties. The unprocessed seaweed is considered nutritious, but is almost tasteless, with only subtle sweetness. It is a natural source of the polysaccharide carrageenan. This is used to make carrageenan extract, which is an ingredient that is widely found in the food industry as a gelling medium. Suitable for the vegan diet.