A complex polysaccharide occurring in the cell walls of the brown algae (Phaeophyta). Chemical formula (C6H8O6)n and density 1.601 g/cm3 . Algin strongly absorbs water to form a viscous gel. It is produced commercially from a variety of species of Laminaria and from Macrocystis pyrifera in the form of alginates, which are used mainly as a stabilizer and texturing agent in the food industry.