Ammonium alginate

E number E403INS 403CAS 9005-34-9

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

Ammonium alginate is a seaweed-derived thickener and stabiliser, one of the alginate family used to gel and thicken without heat.

Where it is and isn’t permitted

Status of Ammonium alginate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 184.1133retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

9 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
  • 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
  • 11.4 Other sugars and syrups (e.g. xylose, maple syrup, sugar toppings) — GMP
CXS 192-1995 Table Three, INS 403and 9 further provisionsretrieved 2026-09-07

What it is made from

Made by neutralising alginic acid, extracted from brown seaweed, with ammonia.

  • Vegan
  • Vegetarian
CAS registry number
9005-34-9
InChIKey
GKFPPCXIBHQRQT-UHFFFAOYSA-N
PubChem
CID 6850754

Every name it appears under

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

E number

  • E403

INS number

  • 403

CAS registry number

  • 9005-34-9

As it appears in regulation

  • Ammonium alginate

Other names

  • Ammonium alginate
  • E 403
  • GKFPPCXIBHQRQT-UHFFFAOYSA-N
  • Kaltostat

Systematic names

  • 3-((6-carboxy-3,4-dihydroxy-5-methoxytetrahydro-2H-pyran-2-yl)oxy)-4,5-dihydroxy-6-methoxytetrahydro-2H-pyran-2-carboxylic acid
  • 6-(2-carboxy-4,5-dihydroxy-6-methoxyoxan-3-yl)oxy-4,5-dihydroxy-3-methoxyoxane-2-carboxylic 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/ammonium-alginate.json