Other applications of carrageenans include uses in pharmaceutical, cosmetics, and various coatings such as paints and inks. Common food uses of carrageenans are in ice cream and pudding. The third class of phycolloids are the algins or algenic acids. Algins is a major constituent of all brown algae. There are some 897 known chemical members of this family.
Alginic acids are commercially important in the production of rubber and textiles.
Before World War II, Japan was the only major producer of algenic acid. During the war, the California algenic acid industry was made. The salts of algins produce a clear, tough film which is used extensively as thickeners, coagulants, or flocculants in many foods. Microalgae is generally referred to as organisms that are less than 2mm in diameter. Today, microalgae are cultivated directly for food or for products produced by the algal cell.