Flavor ingredient regulatory record

2-Acetoxy-3-butanone

2-Acetoxy-3-butanone is an ester in the fruity family, FEMA GRAS under FEMA number 3526 (CAS 4906-24-5). Its odor is sweet, fruity, apple, caramel, estery.

FEMA
3526
CAS
4906-24-5
JECFA
406
EU FL
09.186
Formula
C6H10O3

GRAS status: FEMA GRAS, publication 11. Recorded by FDA in the Substances Added to Food inventory under CAS 4906-24-5.

Structure

2D structure of 2-Acetoxy-3-butanone
Structure of 2-Acetoxy-3-butanone, C6H10O3. Drawn from the canonical SMILES.

Identity

IUPAC name 3-oxobutan-2-yl acetate
CAS number 4906-24-5
FEMA number 3526
Molecular formula C6H10O3
Molecular weight 130.14 g/mol
SMILES CC(=O)OC(C)C(C)=O
InChIKey ZKPTYCJWRHHBOW-UHFFFAOYSA-N
PubChem CID 521246
FDA UNII 2L4E9Q73KY
EPA DTXSID DTXSID60964154
Chemical class Ester
Boiling point 75 °C
Flash point 20 °C

Also known as: 2-Butanone, 3-(acetyloxy)-, 2-Butanone, 3-hydroxy-, acetate, 3-(Acetyloxy)-2-butanone, 3-Acetoxy-2-butanone, Acetoin acetate, 3-Acetyloxy-2-butanone, Acetic acid 1-methyl-2-oxopropyl ester, 3-Oxobutan-2-yl acetate, acetoin acetate, 3-acetoxy-2-butanone, 2-butanone, 3-(acetyloxy)-, 3-(acetyloxy)-2-butanone.

Can 2-Acetoxy-3-butanone be labeled natural?

Since 2-Acetoxy-3-butanone is found in nature, US labeling follows how it was obtained: natural flavor from a natural source and a natural process, artificial when 2-Acetoxy-3-butanone is synthesized. The EU and UK follow the same logic without a middle class; Mercosur and Mexico label synthetic 2-Acetoxy-3-butanone identical-to-natural.

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

2-Acetoxy-3-butanone is FEMA GRAS under FEMA number 3526. 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 09.186, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.

JECFA (WHO / FAO)

JECFA number 406, evaluated at the 51st meeting in 1998. No safety concern at current levels of intake when used as a flavouring agent.

JECFA monograph

Other US flags

Not on the California Proposition 65 list.

Odor and taste

Odor: Sweet, fruity, apple, caramel, estery.

Where it is used

2-Acetoxy-3-butanone is used in beverage, confection, fruit flavors, bakery and desserts, typically as a fruity note.

Structurally similar flavor ingredients

Flavor ingredients with a GRAS determination closest to 2-Acetoxy-3-butanone by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.

MaterialFEMASimilarityOccurrence
Propyl acetate292588%In nature
2,3-Hexanedione255886%In nature
3-Oxobutanal dimethyl acetal338178%In nature
Methyl thiobutyrate331078%In nature
2-Methyl-5-(methylthio)furan336676%In nature

More esters in this index

alpha-Terpinyl acetate · 2-Phenoxyethyl propionate · Butyl anthranilate · Ethyl butyrate · Cinnamyl formate · Butyl salicylate

2-Acetoxy-3-butanone FAQ

Does 2-Acetoxy-3-butanone have FEMA GRAS status?

2-Acetoxy-3-butanone holds FEMA GRAS status under FEMA number 3526. It is also codified at 21 CFR 172.515.

How do I cite 2-Acetoxy-3-butanone by FEMA or CAS number?

Cite 2-Acetoxy-3-butanone as FEMA 3526 or CAS 4906-24-5; both point to the same entry. FEMA files it in the fruity flavor category.

Can 2-Acetoxy-3-butanone be labeled a natural flavor?

2-Acetoxy-3-butanone occurs in nature, so the label depends on the route: 2-Acetoxy-3-butanone won from a natural source by a physical, enzymatic or microbiological process is natural flavor in the United States, and synthesized 2-Acetoxy-3-butanone is artificial. The EU and UK grant the natural claim only to that natural route; Mercosur and Mexico call synthetic material identical-to-natural.

Can 2-Acetoxy-3-butanone be used in the EU and UK?

2-Acetoxy-3-butanone is on the EU Union List of flavouring substances as FL 09.186 (Annex I Part A) under Regulation 1334/2008.

Has JECFA evaluated 2-Acetoxy-3-butanone?

Yes. JECFA number 406, evaluated at the 51st meeting in 1998. Conclusion: No safety concern at current levels of intake when used as a flavouring agent.

What does 2-Acetoxy-3-butanone smell and taste like, and where is it used?

The odor of 2-Acetoxy-3-butanone is sweet, fruity, apple, caramel, estery. Typical uses are beverage, confection, fruit flavors, bakery and desserts.

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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 ACETYL METHYL CARBINYL ACETATE under CAS 4906-24-5 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.