alginic acid

an insoluble, colloidal acid, (C6H8O6)n, found in the cell walls of various kelps, especially brown kelps, known chiefly in the form of its salts, and used as a thickening or stabilizing agent in foodstuffs, especially ice cream, and for sizing paper.

a white or yellowish powdery polysaccharide having marked hydrophilic properties. Extracted from kelp, it is used mainly in the food and textile industries and in cosmetics and pharmaceuticals. Formula: (C 6 H 8 O 6) n; molecular wt: 32 000–250 000