Flavor ingredient regulatory record

Propyleneglycol monobutyrate

Propyleneglycol monobutyrate is an ester in the fruity family, FEMA GRAS under FEMA number 4488 (CAS 29592-95-8). Its odor is sweet, fruity, buttery, creamy.

FEMA
4488
CAS
29592-95-8
JECFA
1979

GRAS status: FEMA GRAS, publication 24. Recorded by FDA in the Substances Added to Food inventory under CAS 29592-95-8.

Structure

Under review

The structure for Propyleneglycol monobutyrate is still under identity review, so no drawing is shown until the record is confirmed.

Identity

CAS number 29592-95-8
FEMA number 4488
FDA UNII 1Y0H57TG56
EPA DTXSID DTXSID80865497
Chemical class Ester
Boiling point 227 °C

Also known as: Butanoic acid, monoester with 1,2-propanediol, Butyric acid, monoester with 1,2-propanediol, Butyric acid, ester with 1,2-propanediol, Propylene glycol monobutyrate, propylene glycol 1-butyrate, butanoic acid, 2-hydroxypropyl ester, 2-hydroxypropyl butyrate, 2-hydroxypropyl butanoate, butanoic acid, monoester with 1,2-propanediol, propane-1,2-diol 1-butyrate, propylene glycol, monobutyrate, 2-hydroxypropylbutyrate.

Can Propyleneglycol monobutyrate be labeled natural?

Nature occurrence: Not yet found in nature (provisional).

Nature occurrence has not been settled for this substance, so the natural or artificial class is not stated here. The FEMA GRAS status does not depend on it.

Regulatory status, with citations

United States

Propyleneglycol monobutyrate is FEMA GRAS under FEMA number 4488. It is cited in the Code of Federal Regulations at 21 CFR 172.515.

21 CFR 172.515

European Union and United Kingdom

No EU FL number is on file for Propyleneglycol monobutyrate. 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)

JECFA number 1979, evaluated at the 73rd meeting in 2010. 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. Propyleneglycol monobutyrate appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 29592-95-8, where EPA names it Butanoic acid, monoester with 1,2-propanediol.

Inactive in US commerce

EPA designates this substance inactive, so a Notice of Activity Form B is required before anyone manufactures or processes it again. Being FEMA GRAS does not change that. 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, fruity, buttery, creamy.

Where it is used

Propyleneglycol monobutyrate is used in beverage, confection, bakery, dairy and flavoring, typically as a fruity note.

Structurally similar flavor ingredients

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

MaterialFEMASimilarityOccurrence
Propyleneglycol mono-2-methylbutyrate446793%Not determined

More esters in this index

Ethyl 4-(acetylthio)butyrate · Isobutyl salicylate · Allyl cinnamate · Butyl laurate · Allyl phenylacetate · Ethyl 3-oxohexanoate

Propyleneglycol monobutyrate FAQ

Is propyleneglycol monobutyrate FEMA GRAS?

Yes. The FEMA Expert Panel lists propyleneglycol monobutyrate as GRAS under FEMA number 4488. It is also codified at 21 CFR 172.515.

What are the FEMA and CAS numbers for propyleneglycol monobutyrate?

Propyleneglycol monobutyrate is FEMA 4488, CAS 29592-95-8. FEMA files it in the fruity flavor category.

Is propyleneglycol monobutyrate approved in the EU?

No EU FL number is on file for propyleneglycol monobutyrate. It has a JECFA evaluation (JECFA 1979), which the EU list draws on, but the Union List entry itself should be confirmed before EU use.

Has JECFA evaluated propyleneglycol monobutyrate?

Yes. JECFA number 1979, evaluated at the 73rd meeting in 2010. Conclusion: No safety concern at current levels of intake when used as a flavouring agent.

How is propyleneglycol monobutyrate described, and where does it show up?

Flavorists describe propyleneglycol monobutyrate as sweet, fruity, buttery, creamy. It is used in beverage, confection, bakery, dairy and flavoring.

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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 PROPYLENEGLYCOL MONOBUTYRATE under CAS 29592-95-8 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.