Flavor ingredient regulatory record
cis-5-Octenal
cis-5-Octenal is an aldehyde in the fruity family, FEMA GRAS under FEMA number 3749 (CAS 41547-22-2). Its odor is green, fruity, grassy, cucumber, fresh.
- FEMA
- 3749
- CAS
- 41547-22-2
- JECFA
- 323
- EU FL
- 05.128
- Formula
- C8H14O
GRAS status: FEMA GRAS, publication 14. Recorded by FDA in the Substances Added to Food inventory under CAS 41547-22-2.
Structure
Identity
Also known as: 5-Octenal, (5Z)-, 5-Octenal, (Z)-, (5Z)-5-Octenal, (Z)-5-Octenal, (z)-oct-5-enal, 5-octenal, (5z)-, 5-octenal, cis-, (z)-5-octen-1-al, (5z)-5-octenal, (5z)-oct-5-enal, 5-octenal, (z)-, z-5-octenal.
Can cis-5-Octenal be labeled natural?
Nature makes cis-5-Octenal, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial cis-5-Octenal, 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
cis-5-Octenal is FEMA GRAS under FEMA number 3749. 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 05.128, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.
Purity. At least 85%; secondary component 10-15% trans-5-octenal
JECFA (WHO / FAO)
JECFA number 323, evaluated at the 51st meeting in 1998. 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. cis-5-Octenal appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 41547-22-2, where EPA names it 5-Octenal, (5Z)-.
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 regulatory flags
| Flag | EPA definition | What it obliges |
|---|---|---|
| PMN | Indicates a commenced PMN substance. | Nothing new. The substance already went through premanufacture review and someone filed a notice of commencement, which is why it is on the Inventory. It is an existing chemical and needs no new premanufacture notice. Read more |
PMN does not establish: The flag records how the substance arrived, not what may be done with it. Check the flags beside it.
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: Green, fruity, grassy, cucumber, fresh.
Where it is used
cis-5-Octenal is used in beverage, savory dishes, fruit flavors and snacks, typically as a fruity note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to cis-5-Octenal by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| cis-6-Nonenal | 3580 | 97% | In nature |
| (E)-4-Nonenal | 4302 | 97% | In nature |
| Oct-2-enal | 3215 | 96% | In nature |
| Nona-2(trans),6(cis)-dienal | 3377 | 96% | In nature |
| 2-trans,6-trans Nonadienal | 3766 | 96% | In nature |
More aldehydes in this index
Paraldehyde · 3-(2-Furyl)acrolein · 2-(p-Tolyl)propionaldehyde · trans-2-Decenal · 4-Methyl-2-(methylthiomethyl)-2-pentenal · Oct-2-enal
cis-5-Octenal FAQ
Is cis-5-Octenal on the FEMA GRAS list?
It is. FEMA number 3749 covers cis-5-Octenal. The Code of Federal Regulations lists it at 21 CFR 172.515.
What is the FEMA number for cis-5-Octenal?
The FEMA number for cis-5-Octenal is 3749 and its CAS registry number is 41547-22-2. Its flavor category is fruity.
What is cis-5-Octenal used for?
cis-5-Octenal is described as green, fruity, grassy, cucumber, fresh. It shows up in beverage, savory dishes, fruit flavors and snacks.
What did JECFA conclude about cis-5-Octenal?
JECFA evaluated cis-5-Octenal at the 51st meeting in 1998 under JECFA number 323. The panel concluded: No safety concern at current levels of intake when used as a flavouring agent.
Is cis-5-Octenal approved in the EU?
Yes. FL 05.128 is the Union List entry for cis-5-Octenal, annex I Part A, under Regulation 1334/2008, and the UK keeps the same list.
Is cis-5-Octenal natural or artificial?
The process decides for cis-5-Octenal. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic cis-5-Octenal 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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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 CIS-5-OCTENAL under CAS 41547-22-2 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.