Constituent of the wall of brown algae of the genus Laminaria, alginate, or alginic acid, is a biopolymer made up of a chain of subunits of mannuronic acid and guluronic acid. There are different alginic acids, whose structure varies according to the number of subunits present in the molecule.
Alginate, like other polysaccharides, is very hydrophilic and has the capacity to retain up to 140 times its own volume in water.
When associated with calcium, alginate forms a gel that modifies the viscosity of liquids. This physico-chemical property is particularly interesting in the stomach. Alginate is indeed known to limit gastroesophageal reflux and to act as a means of protection against acid reflux in the esophagus. It thus forms an anti-reflux barrier and helps in the prevention of heartburn.
Alginate is a biopolymer derived from brown algae. It finds an application at the level of the digestive sphere, in particular in the event of gastro-œsophageal reflux.