Flavor ingredient regulatory record

epsilon-Decalactone

epsilon-Decalactone is a lactone in the fruity family, FEMA GRAS under FEMA number 3613 (CAS 5579-78-2). Its odor is sweet, creamy, coconut, peach, tropical.

FEMA
3613
CAS
5579-78-2
JECFA
241
EU FL
10.029
Formula
C10H18O2
EC
226-963-9

GRAS status: FEMA GRAS, publication 12. Recorded by FDA in the Substances Added to Food inventory under CAS 5579-78-2.

Structure

2D structure of epsilon-Decalactone
Structure of epsilon-Decalactone, C10H18O2. Drawn from the canonical SMILES.

Identity

IUPAC name 7-butyloxepan-2-one
CAS number 5579-78-2
FEMA number 3613
Molecular formula C10H18O2
Molecular weight 170.25 g/mol
SMILES CCCCC1CCCCC(=O)O1
InChIKey YKVIWISPFDZYOW-UHFFFAOYSA-N
PubChem CID 62583
EC number 226-963-9
FDA UNII 662W32KL4O
EPA DTXSID DTXSID8047551
Chemical class Lactone
Boiling point 108 °C
Flash point 37 °C

Also known as: 2-Oxepanone, 7-butyl-, Decanoic acid, 6-hydroxy-, ε-lactone, 7-Butyl-2-oxepanone, ε-Decalactone, (±)-ε-Decalactone, 6-Decanolide, 7-butyloxepan-2-one, 2-oxepanone, 7-butyl-, 6-butylhexanolide, 6-hydroxydecanoic acid epsilon-lactone, 7-butyl-2-oxepanone, e-decalactone.

Can epsilon-Decalactone be labeled natural?

Nature makes epsilon-Decalactone, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial epsilon-Decalactone, same molecule. The EU and UK grant the natural claim only to that natural route; Mercosur and Mexico call synthetic material 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

epsilon-Decalactone is FEMA GRAS under FEMA number 3613. 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 10.029, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.

JECFA (WHO / FAO)

JECFA number 241, evaluated at the 49th meeting in 1997. 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.

TSCA Inventory status

A flavor ingredient is also an industrial chemical. epsilon-Decalactone appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 5579-78-2, where EPA names it 2-Oxepanone, 7-butyl-.

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: Sweet, creamy, coconut, peach, tropical.

Where it is used

epsilon-Decalactone is used in beverage, confection, dairy, fruit flavors and bakery, typically as a fruity note.

Structurally similar flavor ingredients

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

MaterialFEMASimilarityOccurrence
1,6-Hexalactam423575%In nature
delta-Decalactone236141%In nature
Hydroxynonanoic acid delta-lactone335640%In nature
5-Hydroxyundecanoic acid lactone329439%In nature
gamma-Decalactone236037%In nature

More lactones in this index

gamma-Undecalactone · 2-(2-Hydroxyphenyl)-cyclopropanecarbocyclic acid delta-lactone · Phthalide · 5-Hydroxy-8-undecenoic acid delta-lactone · gamma-Decalactone · delta-Decalactone

epsilon-Decalactone FAQ

Does epsilon-Decalactone have FEMA GRAS status?

epsilon-Decalactone holds FEMA GRAS status under FEMA number 3613. The Code of Federal Regulations lists it at 21 CFR 172.515.

How do I cite epsilon-Decalactone by FEMA or CAS number?

Cite epsilon-Decalactone as FEMA 3613 or CAS 5579-78-2; both point to the same entry. Its flavor category is fruity.

What does epsilon-Decalactone smell and taste like, and where is it used?

The odor of epsilon-Decalactone is sweet, creamy, coconut, peach, tropical. Typical uses are beverage, confection, dairy, fruit flavors and bakery.

What did JECFA conclude about epsilon-Decalactone?

JECFA evaluated epsilon-Decalactone at the 49th meeting in 1997 under JECFA number 241. The panel concluded: No safety concern at current levels of intake when used as a flavouring agent.

Can epsilon-Decalactone be used in the EU and UK?

Yes. FL 10.029 is the Union List entry for epsilon-Decalactone, annex I Part A, under Regulation 1334/2008, and the UK keeps the same list.

Can epsilon-Decalactone be labeled a natural flavor?

The process decides for epsilon-Decalactone. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic epsilon-Decalactone is artificial. The EU and UK grant the natural claim only to that natural route; Mercosur and Mexico call synthetic material identical-to-natural.

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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 EPSILON-DECALACTONE under CAS 5579-78-2 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.