Ethyl maltol

INS 637CAS 4940-11-8

Used as a flavour enhancer.

Ethyl maltol is maltol's stronger sibling — several times more potent, with a caramel and candyfloss character. Unlike maltol it does not occur in nature at all.

Where it is and isn’t permitted

Status of Ethyl maltol 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

5 food categories

highest permitted level 1,000 mg/kg

Show every food category
  • 01.1.4 Flavoured Fluid Milk Drinks — GMP
  • 01.7 Dairy-based desserts (e.g. pudding, fruit or flavoured yoghurt) — 200 mg/kg
  • 03.0 Edible ices, including sherbet and sorbet — 200 mg/kg
  • 05.2 Confectionery including hard and soft candy, nougats, etc. other than food categories 05.1, 05.3, and 05.4 — 1,000 mg/kg
  • 05.3 Chewing gum — 1,000 mg/kg
CXS 192-1995 Table One, INS 637and 4 further provisionsretrieved 2026-09-07

What it is made from

Produced by chemical synthesis. It has no natural source, so it cannot be declared a natural flavour anywhere.

  • Vegan
  • Vegetarian
CAS registry number
4940-11-8
InChIKey
YIKYNHJUKRTCJL-UHFFFAOYSA-N
PubChem
CID 21059

Every name it appears under

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

E number

  • E637

INS number

  • 637

CAS registry number

  • 4940-11-8

Other names

  • 2-Ethyl pyromeconic acid
  • 2-Ethyl-3-hydroxy-4-pyrone
  • 2-Ethyl-3-hydroxy-4H-pyran-4-one
  • 2-Ethyl-3-hydroxy-4H-pyran-4-one, 99%
  • 2-Ethyl-3-hydroxy-4H-pyran-4-one; Ethyl maltol
  • 2-Ethyl-3-hydroxy-pyran-4-one
  • 2-ethyl-3-hydroxypyran-4-one
  • 2-Ethylpyromeconic acid
  • 3-Hydroxy-2-ethyl-.gamma.-pyrone
  • 3-Hydroxy-2-ethyl-1,4-pyrone
  • 3-Hydroxy-2-ethyl-4-pyrone
  • 3-Hydroxy-2-ethyl-4-pyrone11/8/40
  • 3-Hydroxy-2-ethyl-4H-pyran-4-one
  • 3-Hydroxy-2-ethyl-gamma-pyrone
  • 3-Hydroxy-2-ethyl-laquo gammaRaquo -pyrone
  • 4H-PYRAN-4-ONE, 2-ETHYL-3-HYDROXY-
  • 5-18-01-00135 (Beilstein Handbook Reference)
  • 6-ethyl-3-hydroxy-2-methyl-4H-pyran-4-one
  • BRN 1618110
  • Ethyl Hydroxypyrone
  • ETHYL MALTOL
  • Ethyl maltol (Standard)
  • Ethyl maltol Solution in Methanol, 1000ug/mL
  • Ethyl maltol Solution in Methanol, 100ug/mL
  • Ethyl maltol, >=99%, FCC, FG
  • Ethyl maltol, analytical standard
  • Ethyl maltol, Pharmaceutical Secondary Standard; Certified Reference Material
  • Ethyl maltol, United States Pharmacopeia (USP) Reference Standard
  • Ethylmaltol
  • FEMA 3487
  • FEMA No. 3487
  • INS NO.637
  • INS-637
  • Maltol-ethyl
  • Veltol plus

Systematic names

  • 2-ethyl-3-hydroxy-4H-pyran-4-one

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

  • 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/ethyl-maltol.json