Potassium alginate

E number E402INS 402CAS 9005-36-1

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

Potassium alginate is a seaweed thickener and gelling agent used where a sodium-free preparation is wanted.

Where it is and isn’t permitted

Status of Potassium 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 184.1610retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

8 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
  • 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 402and 8 further provisionsretrieved 2026-09-07

What it is made from

Extracted from brown seaweed and isolated as the potassium salt.

  • Vegan
  • Vegetarian
CAS registry number
9005-36-1

Every name it appears under

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

E number

  • E402

INS number

  • 402

CAS registry number

  • 9005-36-1

As it appears in regulation

  • Potassium alginate

Other names

  • E 402
  • Potassium alginate

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/potassium-alginate.json