E400 (Alginic acid) is a complex carbohydrate, linear edible polysaccharide derived from Algin, a natural biodegradable component, a biological polysaccharide and colloidal carbohydrate.

It appears in the form of a white powder. 

What it is used for and where

Algin is a natural, gelling, soluble polymer found in marine algae and extracted from brown algae such as Turbinaria, Cystoseira, Sargassum, Hormophysa. It is available as propylene glycol alginate, ester, precipitate or paste.

Food

Algin is added in dairy products, candies, sweets, jellies. It has the number E400 in the list of European food additives as thickener and stabilizer..

Cosmetics

Binder agent. Ingredient that is used in cosmetic, food and pharmaceutical products as an anti-caking agent with the function of making the product in which it is incorporated silky, compact and homogenous. The binder, either natural such as mucilage, gums and starches or chemical, may be in the form of a powder or liquid.

Skin conditioning agent. It is the mainstay of topical skin treatment by restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants.

Surfactant - Suspending agent. Cosmetic or pharmaceutical suspensions are known to be thermodynamically unstable and it is therefore essential to include in the formulation a suspending agent capable of dispersing any sedimented particulates and reducing the rate of sedimentation. The presence of this agent increases the consistency of the suspension medium and exerts a protective colloidal action with a surfactant action.

Other uses

It is used in thickening textile paints, paper and textile sizing.

CAS: 9005-32-7

EC number 232-680-1