Flavor ingredient regulatory record
2-Methylhexanoic acid
2-Methylhexanoic acid is an acid in the fruity family, FEMA GRAS under FEMA number 3191 (CAS 4536-23-6). Its odor is fruity, fatty, waxy, floral.
- FEMA
- 3191
- CAS
- 4536-23-6
- JECFA
- 265
- EU FL
- 08.035
- Formula
- C7H14O2
GRAS status: FEMA GRAS, publication 4. Recorded by FDA in the Substances Added to Food inventory under CAS 4536-23-6.
Structure
Identity
Also known as: Hexanoic acid, 2-methyl-, Caproic acid, α-methyl-, α-Methylcaproic acid, 2-Hexanecarboxylic acid, 2-Methylcaproic acid, (±)-2-Methylhexanoic acid, 2-methylcaproic acid, hexanoic acid, 2-methyl-, 2-hexanecarboxylic acid, alpha-methylcaproic acid, 2-methyl-hexanoic acid, .alpha.-methylcaproic acid.
Can 2-Methylhexanoic acid be labeled natural?
The process decides for 2-Methylhexanoic acid. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic 2-Methylhexanoic acid is artificial. The EU and UK follow the same logic without a middle class; Mercosur and Mexico label synthetic 2-Methylhexanoic acid 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-Methylhexanoic acid is FEMA GRAS under FEMA number 3191. It is cited in the Code of Federal Regulations at 21 CFR 172.515.
European Union and United Kingdom
Listed on the Union List of flavouring substances as FL 08.035, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.
JECFA (WHO / FAO)
JECFA number 265, evaluated at the 49th meeting in 1997. No safety concern at current levels of intake when used as a flavouring agent.
Other US flags
Not on the California Proposition 65 list.
TSCA Inventory status
A flavor ingredient is also an industrial chemical. 2-Methylhexanoic acid appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 4536-23-6, where EPA names it Hexanoic acid, 2-methyl-.
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: Fruity, fatty, waxy, floral.
Where it is used
2-Methylhexanoic acid is used in beverage, confection, dairy and flavoring agents, typically as a fruity note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to 2-Methylhexanoic acid by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| Hexanoic acid | 2559 | 92% | In nature |
| 4-Ethyloctanoic acid | 3800 | 84% | In nature |
| 2-Methylheptan-3-one | 4000 | 83% | In nature |
| 2-Methylheptanoic acid | 2706 | 80% | In nature |
| 5-Methylhexanoic acid | 3572 | 79% | In nature |
More acids in this index
(E,E)-2,4-Hexadienoic acid · cis-3-Hexenoic acid · 3-Methoxybenzoic acid · Hept-2-enoic acid · cis-4-(2,2,3-Trimethylcyclopentyl)butanoic acid · 5-Oxododecanoic acid
2-Methylhexanoic acid FAQ
Is 2-Methylhexanoic acid on the FEMA GRAS list?
It is. FEMA number 3191 covers 2-Methylhexanoic acid. The Code of Federal Regulations lists it at 21 CFR 172.515.
What is the FEMA number for 2-Methylhexanoic acid?
The FEMA number for 2-Methylhexanoic acid is 3191 and its CAS registry number is 4536-23-6. Its flavor category is fruity.
What is 2-Methylhexanoic acid used for?
2-Methylhexanoic acid is described as fruity, fatty, waxy, floral. It shows up in beverage, confection, dairy and flavoring agents.
What did JECFA conclude about 2-Methylhexanoic acid?
JECFA evaluated 2-Methylhexanoic acid at the 49th meeting in 1997 under JECFA number 265. The panel concluded: No safety concern at current levels of intake when used as a flavouring agent.
Is 2-Methylhexanoic acid approved in the EU?
Yes. FL 08.035 is the Union List entry for 2-Methylhexanoic acid, annex I Part A, under Regulation 1334/2008, and the UK keeps the same list.
Is 2-Methylhexanoic acid natural or artificial?
Nature makes 2-Methylhexanoic acid, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial 2-Methylhexanoic acid, same molecule. 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 2-METHYLHEXANOIC ACID under CAS 4536-23-6 and carries its FEMA number, its JECFA flavor number. The inventory is searchable at FDA. FDA records its technical effect as flavor enhancer, 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.