Metatartaric acid

E number E353INS 353CAS 39469-81-3

Used as an acidity regulator — Codex also lists it as emulsifier, stabilizer, thickener.

Metatartaric acid is used in winemaking to stop tartrate crystals forming in the bottle. It is a wine treatment rather than a general food acid.

Where it is and isn’t permitted

Status of Metatartaric acid by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationNot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

1 food category

highest permitted level 100 mg/kg

CXS 192-1995 Table One, INS 353, food category 14.2.3retrieved 2026-09-07

What it is made from

Made by heating tartaric acid, which partially polymerises it. Its effect is temporary, since it slowly reverts to tartaric acid in the bottle.

  • Vegan
  • Vegetarian
CAS registry number
39469-81-3
InChIKey
KWBYTEOPKORPPY-UHFFFAOYSA-N
PubChem
CID 92024228

Every name it appears under

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

E number

  • E353

INS number

  • 353

CAS registry number

  • 39469-81-3
  • 4450-95-7

Other names

  • 2,2'-(3,6-Dioxo-1,4-dioxane-2,5-diyl)bis(2-hydroxyacetic acid)
  • 2,2'-(3,6-Dioxo-1,4-dioxane-2,5-diyl)bis(hydroxyacetic acid)
  • Ditartaric acid
  • E 353
  • I+/-2,I+/-5-Dihydroxy-3,6-dioxo-1,4-dioxane-2,5-diacetic acid
  • KWBYTEOPKORPPY-UHFFFAOYSA-N
  • METATARTARIC ACID

Hazard reference values

Values set by assessing bodies. A body that has not set a value is not listed here.
TypeValuePopulationAssessed byOpinion
ADI240 mg/kg bw/dayconsumersEFSA FAF2020

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

  • 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/metatartaric-acid.json