Flavor ingredient regulatory record

4-Hydroxy-2,5-dimethyl-3(2H)-furanone

4-Hydroxy-2,5-dimethyl-3(2H)-furanone is a furanone in the fruity family, FEMA GRAS under FEMA number 3174 (CAS 3658-77-3). Its odor is strawberry, caramel, cotton candy, burnt pineapple.

FEMA
3174
CAS
3658-77-3
JECFA
1446
EU FL
13.010
Formula
C6H8O3
EC
222-908-8

GRAS status: FEMA GRAS, publication 4. Recorded by FDA in the Substances Added to Food inventory under CAS 3658-77-3.

Structure

2D structure of 4-Hydroxy-2,5-dimethyl-3(2H)-furanone
Structure of 4-Hydroxy-2,5-dimethyl-3(2H)-furanone, C6H8O3. Drawn from the canonical SMILES.

Identity

IUPAC name 4-hydroxy-2,5-dimethylfuran-3-one
CAS number 3658-77-3
FEMA number 3174
Molecular formula C6H8O3
Molecular weight 128.13 g/mol
SMILES CC1=C(O)C(=O)C(C)O1
InChIKey INAXVXBDKKUCGI-UHFFFAOYSA-N
PubChem CID 19309
EC number 222-908-8
FDA UNII 20PI8YZP7A
EPA DTXSID DTXSID0041517
Chemical class Furanone
Boiling point 216 °C
Flash point 94 °C

Also known as: 3(2H)-Furanone, 4-hydroxy-2,5-dimethyl-, 2,5-Dimethyl-4-hydroxy-3(2H)-furanone, 2,5-Dimethyl-4-hydroxy-2,3-dihydrofuran-3-one, 4-Hydroxy-2,5-dimethyl-2H-furan-3-one, 2,5-Dimethyl-4,5-dihydrofuran-3-ol-4-one, 4-Hydroxy-2,5-dimethyl-2,3-dihydrofuran-3-one, Furaneol, 2,5-Dimethyl-3-hydroxy-4-oxo-4,5-dihydrofuran, Alletone, Pineapple ketone, 4-Hydroxy-2,5-Dimethyl-3-oxo-2,3-dihydrofuran, 4-Hydroxy-2,5-dimethyl-3-furanone.

Can 4-Hydroxy-2,5-dimethyl-3(2H)-furanone be labeled natural?

Since 4-Hydroxy-2,5-dimethyl-3(2H)-furanone is found in nature, US labeling follows how it was obtained: natural flavor from a natural source and a natural process, artificial when 4-Hydroxy-2,5-dimethyl-3(2H)-furanone is synthesized. In the EU and UK the natural claim likewise needs the natural route, while Mercosur and Mexico keep a third class, identical-to-natural, for the synthetic material.

United States
Natural or artificial, by process
European Union and UK
Natural only from natural material
Mercosur and Mexico
Natural or identical-to-natural

How each market defines the classes: natural vs artificial flavor under 21 CFR 101.22.

Regulatory status, with citations

United States

4-Hydroxy-2,5-dimethyl-3(2H)-furanone is FEMA GRAS under FEMA number 3174. It is cited in the Code of Federal Regulations at 21 CFR 172.515.

21 CFR 172.515

European Union and United Kingdom

Listed on the Union List of flavouring substances as FL 13.010, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (EFSA). The UK retains the same list.

JECFA (WHO / FAO)

JECFA number 1446, evaluated at the 63rd meeting in 2004. no safety concern at current levels of intake.

JECFA monograph

Other US flags

Not on the California Proposition 65 list.

TSCA Inventory status

A flavor ingredient is also an industrial chemical. 4-Hydroxy-2,5-dimethyl-3(2H)-furanone appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 3658-77-3, where EPA names it 3(2H)-Furanone, 4-hydroxy-2,5-dimethyl-.

Active in US commerce

EPA designates this substance active, so no Notice of Activity Form B is required before manufacturing. What active and inactive mean.

EPA publishes no regulatory flags on this listing. What the flags mean.

From the EPA non-confidential TSCA Inventory, July 2026 release. EPA also maintains a confidential portion it does not publish. Search the Inventory by CAS number.

Odor and taste

Odor: Strawberry, caramel, cotton candy, burnt pineapple. Detectable at about 0.04 ppm.

Taste: Sweet, strawberry, caramel.

Where it is used

4-Hydroxy-2,5-dimethyl-3(2H)-furanone is used in strawberry, pineapple, caramel and tropical, typically as a fruity note.

Structurally similar flavor ingredients

Flavor ingredients with a GRAS determination closest to 4-Hydroxy-2,5-dimethyl-3(2H)-furanone by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.

MaterialFEMASimilarityOccurrence
4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one363494%In nature
Maltol265691%In nature
2,5-Dimethylfuran-3(2H)-one410188%Not determined
2-Ethyl-4-hydroxy-5-methyl-3(2H)-furanone362383%In nature
4-Hydroxy-5-methyl-3(2H)-furanone363579%In nature

More furanones in this index

4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one

4-Hydroxy-2,5-dimethyl-3(2H)-furanone FAQ

Is 4-Hydroxy-2,5-dimethyl-3(2H)-furanone FEMA GRAS?

Yes. The FEMA Expert Panel lists 4-Hydroxy-2,5-dimethyl-3(2H)-furanone as GRAS under FEMA number 3174. It is also codified at 21 CFR 172.515.

What are the FEMA and CAS numbers for 4-Hydroxy-2,5-dimethyl-3(2H)-furanone?

4-Hydroxy-2,5-dimethyl-3(2H)-furanone is FEMA 3174, CAS 3658-77-3. FEMA files it in the fruity flavor category.

Does 4-Hydroxy-2,5-dimethyl-3(2H)-furanone count as natural in the US and the EU?

4-Hydroxy-2,5-dimethyl-3(2H)-furanone occurs in nature, so the label depends on the route: 4-Hydroxy-2,5-dimethyl-3(2H)-furanone won from a natural source by a physical, enzymatic or microbiological process is natural flavor in the United States, and synthesized 4-Hydroxy-2,5-dimethyl-3(2H)-furanone is artificial. The EU and UK follow the same logic without a middle class; Mercosur and Mexico label synthetic 4-Hydroxy-2,5-dimethyl-3(2H)-furanone identical-to-natural.

Is 4-Hydroxy-2,5-dimethyl-3(2H)-furanone on the EU Union List?

4-Hydroxy-2,5-dimethyl-3(2H)-furanone is on the EU Union List of flavouring substances as FL 13.010 (Annex I Part A) under Regulation 1334/2008.

Has JECFA evaluated 4-Hydroxy-2,5-dimethyl-3(2H)-furanone?

Yes. JECFA number 1446, evaluated at the 63rd meeting in 2004. Conclusion: no safety concern at current levels of intake.

How is 4-Hydroxy-2,5-dimethyl-3(2H)-furanone described, and where does it show up?

Flavorists describe 4-Hydroxy-2,5-dimethyl-3(2H)-furanone as strawberry, caramel, cotton candy, burnt pineapple. On the palate it is sweet, strawberry, caramel. Its odor threshold is about 0.04 ppm. It is used in strawberry, pineapple, caramel and tropical.

Ingredient lookup

Check an ingredient

Start typing to search the ingredient corpus.

Or browse every ingredient page, A to Z.

Guides: What Is FEMA GRAS? · Natural vs artificial · Filing a GRAS notification

Check 4-Hydroxy-2,5-dimethyl-3(2H)-furanone in a formula

Screened against FEMA GRAS, 21 CFR and EU rules as you build. Free to start.

Sources and attribution. The identity and regulatory facts on this page are taken from the FDA Substances Added to Food inventory, a US government record, which lists this substance as 4-HYDROXY-2,5-DIMETHYL-3(2H)-FURANONE under CAS 3658-77-3 and carries its FEMA number, its JECFA flavor number. The inventory is searchable at FDA. FDA records its technical effect as flavoring agent or adjuvant.

A FEMA GRAS conclusion is reached by the Expert Panel of the Flavor and Extract Manufacturers Association of the United States, and the FEMA number names that conclusion. FEMA publishes its own entry for this substance in the FEMA Flavor Library, which is the authoritative record of what the Panel decided and is worth reading alongside this page.

Ambrose Compliance is not affiliated with, endorsed by, or sponsored by FEMA. FEMA and FEMA GRAS are used here as identifiers for a published regulatory determination, not as marks of any relationship between FEMA and Ambrose.

About this page. Facts come from the FDA Substances Added to Food inventory, the Code of Federal Regulations, the EPA TSCA Inventory, the EU Union List, JECFA and the Ambrose database, with FEMA's published determination cited where it applies; parts of the text are written by Ambrose AI, which can make mistakes. Check the cited source before relying on anything here. This is not regulatory or legal advice.