Irish Moss extract or carrageen is a jelly-like substance obtained from the red alga Chondrus crispus. The water-soluble extract is a mixed salt sulfate ester of the polysaccharide complex, composed principally of D-galactopyranose and some L-galactose units, 2-ketoglu-conic acid units, and nonreducing sugar units.
It is commonly used as a thickening agent in many household items such as sauces, toothpaste and even shoe polish. Carrageen is also well known in the medical profession. Historically the plant has been used for laxative purposes and especially prized for its ability to prevent blood clots. In this paper, the researcher breaks down the chemical complexities of carrageen and attempts to understand what exactly makes it such an effective emollient and demulcent.