Alginic acid

E number E400INS 400CAS 9005-32-7

Used as an emulsifier — Codex also lists it as bulking agent, carrier, foaming, agent, gelling agent, glazing agent, humectant, sequestrant, stabilizer, thickener.

Alginic acid is a thickener and gelling agent extracted from brown seaweed. It is the parent acid of the alginate salts, which are more commonly used because they dissolve readily.

Where it is and isn’t permitted

Status of Alginic acid by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
Jurisdiction	Status	Scope and limits	Citation
United StatesFood and Drug Administration	Permitted		21 CFR 184.1011retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFA	Permitted, with conditions	18 food categories no numerical limit (good manufacturing practice) Show every food category 01.2.1.1 Fermented milks (plain), not heat-treated after fermentation — GMP 01.2.1.2 Fermented milks (plain), heat-treated after fermentation — GMP 01.4.1 Pasteurized cream (plain) — GMP 01.4.2 Sterilized and UHT creams, whipping and whipped creams, and reduced fat creams (plain) — GMP 04.1.1.2 Surface-treated fresh fruit — GMP 04.2.2.7 Fermented vegetable (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera) and seaweed products, excluding fermented soybean products of food categories 06.8.6, 06.8.7, 12.9.1, — GMP 06.4.1 Fresh pastas and noodles and like products — GMP 06.4.2 Dried pastas and noodles and like products — GMP 09.2.1 Frozen fish, fish fillets, and fish products, including molluscs, crustaceans, and echinoderms — GMP 09.2.2 Frozen battered fish, fish fillets and fish products, including molluscs, crustaceans, and echinoderms — GMP 09.2.3 Frozen minced and creamed fish products, including molluscs, crustaceans, and echinoderms — GMP 09.2.4.1 Cooked fish and fish products — GMP 09.2.4.2 Cooked molluscs, crustaceans, and echinoderms — GMP 09.2.4.3 Fried fish and fish products, including molluscs, crustaceans, and echinoderms — GMP 09.2.5 Smoked, dried, fermented, and/or salted fish and fish products, including molluscs, crustaceans, and echinoderms — GMP 11.4 Other sugars and syrups (e.g. xylose, maple syrup, sugar toppings) — GMP 12.1.2 Salt substitutes — GMP 14.1.5 Coffee, coffee substitutes, tea, herbal infusions, and other hot cereal and grain beverages, excluding cocoa — GMP	CXS 192-1995 Table Three, INS 400and 18 further provisionsretrieved 2026-09-07

What it is made from

Extracted with alkali from brown seaweeds, chiefly species of Laminaria, Macrocystis and Ascophyllum, then precipitated as the free acid.

Vegan
Vegetarian

CAS registry number: 9005-32-7

Every name it appears under

7 recorded names. A label may use any of them.

E number

E400

INS number

CAS registry number

9005-32-7

As it appears in regulation

Alginic acid

Other names

Alginic acid
E 400

Systematic names

2,6-anhydro-7-deoxy-3-O-(4-O-methyl-beta-D-mannopyranuronosyl)-L-glycero-D-allo-heptonic acid

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

ecfr retrieved 2026-09-07
gsfa retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/alginic-acid.json