Flavor ingredient regulatory record
4-Methylpentanoic acid
4-Methylpentanoic acid is an acid in the fruity family, FEMA GRAS under FEMA number 3463 (CAS 646-07-1). Its odor is fruity, sweet, apple, berry, floral.
- FEMA
- 3463
- CAS
- 646-07-1
- JECFA
- 264
- EU FL
- 08.057
- Formula
- C6H12O2
GRAS status: FEMA GRAS, publication 9. Recorded by FDA in the Substances Added to Food inventory under CAS 646-07-1.
Structure
Identity
Also known as: Pentanoic acid, 4-methyl-, Valeric acid, 4-methyl-, Isocaproic acid, 4-Methylvaleric acid, 4,4-Dimethylbutanoic acid, Isobutylacetic acid, Isohexanoic acid, Isohexoic acid, NSC 4126, 4-methylvaleric acid, isocaproic acid, isohexanoic acid.
Can 4-Methylpentanoic acid be labeled natural?
The process decides for 4-Methylpentanoic acid. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic 4-Methylpentanoic acid is artificial. 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-Methylpentanoic acid is FEMA GRAS under FEMA number 3463. 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 08.057, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.
JECFA (WHO / FAO)
JECFA number 264, evaluated at the 49th meeting in 1997. no safety concern at current levels of intake.
Other US flags
Not on the California Proposition 65 list.
TSCA Inventory status
A flavor ingredient is also an industrial chemical. 4-Methylpentanoic acid appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 646-07-1, where EPA names it Pentanoic acid, 4-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, sweet, apple, berry, floral.
Where it is used
4-Methylpentanoic acid is used in beverage, confection, fruit flavors, dairy and savory dishes, typically as a fruity note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to 4-Methylpentanoic acid by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| (E,Z)-4-Methylpent-2-enoic acid | 4180 | 96% | In nature |
| Valeric acid | 3101 | 93% | In nature |
| 3-Methylpentanoic acid | 3437 | 92% | In nature |
| 2-Methylvaleric acid | 2754 | 83% | In nature |
| (E)-2-Pentenoic acid | 4193 | 80% | In nature |
More acids in this index
Methyl-3-pentenoic acid · 3-Methoxybenzoic acid · 5-Oxodecanoic acid · 2-Methoxybenzoic acid · cis-5-Octenoic acid · 3-Methylcrotonic acid
4-Methylpentanoic acid FAQ
Does 4-Methylpentanoic acid have FEMA GRAS status?
4-Methylpentanoic acid holds FEMA GRAS status under FEMA number 3463. The Code of Federal Regulations lists it at 21 CFR 172.515.
How do I cite 4-Methylpentanoic acid by FEMA or CAS number?
Cite 4-Methylpentanoic acid as FEMA 3463 or CAS 646-07-1; both point to the same entry. Its flavor category is fruity.
What does 4-Methylpentanoic acid smell and taste like, and where is it used?
The odor of 4-Methylpentanoic acid is fruity, sweet, apple, berry, floral. Typical uses are beverage, confection, fruit flavors, dairy and savory dishes.
What did JECFA conclude about 4-Methylpentanoic acid?
JECFA evaluated 4-Methylpentanoic acid at the 49th meeting in 1997 under JECFA number 264. The panel concluded: no safety concern at current levels of intake.
Can 4-Methylpentanoic acid be used in the EU and UK?
Yes. FL 08.057 is the Union List entry for 4-Methylpentanoic acid, annex I Part A, under Regulation 1334/2008, and the UK keeps the same list.
Can 4-Methylpentanoic acid be labeled a natural flavor?
Nature makes 4-Methylpentanoic acid, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial 4-Methylpentanoic acid, same molecule. The EU and UK follow the same logic without a middle class; Mercosur and Mexico label synthetic 4-Methylpentanoic acid 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 4-METHYLPENTANOIC ACID under CAS 646-07-1 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.