Flavor ingredient regulatory record
2-Pyrrolidone
2-Pyrrolidone is a lactam in the nutty family, FEMA GRAS under FEMA number 4829 (CAS 616-45-5). Its odor is nutty, creamy, slightly sweet, earthy.
- FEMA
- 4829
- CAS
- 616-45-5
- Formula
- C4H7NO
GRAS status: FEMA GRAS. Source: FEMA Flavor Ingredient Library.
Structure
Identity
Also known as: 2-Pyrrolidinone, γ-Butyrolactam, α-Pyrrolidone, γ-Aminobutyric lactam, α-Pyrrolidinone, Butyrolactam, Pyrrolidone, γ-Aminobutyrolactam, 2-Oxopyrrolidine, 2-Pyrol, 4-Aminobutyric acid lactam, γ-Aminobutyric acid lactam.
Can 2-Pyrrolidone be labeled natural?
Nature makes 2-Pyrrolidone, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial 2-Pyrrolidone, same molecule. 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
2-Pyrrolidone is FEMA GRAS under FEMA number 4829. It is cited in the Code of Federal Regulations at 21 CFR 172.515.
European Union and United Kingdom
No EU FL number is on file for 2-Pyrrolidone. That is not a finding either way. The Union List covers defined flavouring substances, so natural complex materials are handled as flavouring preparations under Parts B to F and never receive a number, and substances used as additives sit under Regulation 1333/2008 instead. Confirm the position before EU or UK use.
JECFA (WHO / FAO)
2-Pyrrolidone has not been evaluated by JECFA as a flavouring agent, or no evaluation is on file.
Other US flags
Not on the California Proposition 65 list.
TSCA Inventory status
A flavor ingredient is also an industrial chemical. 2-Pyrrolidone appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 616-45-5, where EPA names it 2-Pyrrolidinone.
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: Nutty, creamy, slightly sweet, earthy.
Taste: Umami, savory, mild.
Where it is used
2-Pyrrolidone is used in dairy, snacks, seasonings and flavoring agents, typically as a nutty note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to 2-Pyrrolidone by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| 4-Hydroxybutyric acid lactone | 3291 | 95% | In nature |
More lactams in this index
2-Pyrrolidone FAQ
Is 2-Pyrrolidone on the FEMA GRAS list?
It is. FEMA number 4829 covers 2-Pyrrolidone. The Code of Federal Regulations lists it at 21 CFR 172.515.
What is the FEMA number for 2-Pyrrolidone?
The FEMA number for 2-Pyrrolidone is 4829 and its CAS registry number is 616-45-5. Its flavor category is nutty.
What is 2-Pyrrolidone used for?
2-Pyrrolidone is described as nutty, creamy, slightly sweet, earthy. On the palate it is umami, savory, mild. It shows up in dairy, snacks, seasonings and flavoring agents.
Is 2-Pyrrolidone natural or artificial?
The process decides for 2-Pyrrolidone. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic 2-Pyrrolidone 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.
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Guides: What Is FEMA GRAS? · Natural vs artificial · Filing a GRAS notification
Check 2-Pyrrolidone in a formula
Screened against FEMA GRAS, 21 CFR and EU rules as you build. Free to start.
Sources and attribution. The FEMA number and GRAS status on this page name a conclusion reached by the Expert Panel of the Flavor and Extract Manufacturers Association of the United States. FDA does not list this substance by FEMA number in its Substances Added to Food inventory. Its identity is attested by EPA TSCA Chemical Substance Inventory, matched on CAS 616-45-5.
FEMA publishes its own entry for this substance in the FEMA Flavor Library, which is the authoritative record 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.