Flavor ingredient regulatory record
Isoamyl isothiocyanate
Isoamyl isothiocyanate is an isothiocyanate in the sulfur family, FEMA GRAS under FEMA number 4423 (CAS 628-03-5). Its odor is pungent, mustard-like, sharp, earthy.
- FEMA
- 4423
- CAS
- 628-03-5
- JECFA
- 1887
- Formula
- C6H11NS
GRAS status: FEMA GRAS, publication 23. Recorded by FDA in the Substances Added to Food inventory under CAS 628-03-5.
Structure
Identity
Also known as: Butane, 1-isothiocyanato-3-methyl-, Isothiocyanic acid, isopentyl ester, 1-Isothiocyanato-3-methylbutane, Isopentyl isothiocyanate, 3-Methylbutyl isothiocyanate, 3-methylbutyl isothiocyanate, 1-isothiocyanato-3-methylbutane, butane, 1-isothiocyanato-3-methyl-, isopentyl isothiocyanate, isoamyl isothiocyanate [fhfi], isothiocyanic acid, isopentyl ester, 3-methylbutylisothiocyanate.
Can Isoamyl isothiocyanate be labeled natural?
The process decides for isoamyl isothiocyanate. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic isoamyl isothiocyanate 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
Isoamyl isothiocyanate is FEMA GRAS under FEMA number 4423. 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 Isoamyl isothiocyanate. 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 1887, evaluated at the 69th meeting in 2008. no safety concern at current levels of intake.
Other US flags
Not on the California Proposition 65 list.
Odor and taste
Odor: Pungent, mustard-like, sharp, earthy.
Where it is used
Isoamyl isothiocyanate is used in condiments, seasonings, savory dishes and snacks, typically as a sulfur note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to Isoamyl isothiocyanate by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| Butyl isothiocyanate | 4082 | 97% | In nature |
| Hexyl isothiocyanate | 4422 | 80% | In nature |
| 5-(Methylthio)pentyl isothiocyanate | 4416 | 80% | In nature |
| Amyl isothiocyanate | 4417 | 78% | In nature |
| 5-Hexenyl isothiocyanate | 4421 | 78% | In nature |
More isothiocyanates in this index
3-(Methylthio)propyl isothiocyanate · 2-Butyl isothiocyanate · Hexyl isothiocyanate · Isopropyl isothiocyanate · 5-(Methylthio)pentyl isothiocyanate · Methyl isothiocyanate
Isoamyl isothiocyanate FAQ
Does isoamyl isothiocyanate have FEMA GRAS status?
Isoamyl isothiocyanate holds FEMA GRAS status under FEMA number 4423. The Code of Federal Regulations lists it at 21 CFR 172.515.
How do I cite isoamyl isothiocyanate by FEMA or CAS number?
Cite isoamyl isothiocyanate as FEMA 4423 or CAS 628-03-5; both point to the same entry. Its flavor category is sulfur.
What does isoamyl isothiocyanate smell and taste like, and where is it used?
The odor of isoamyl isothiocyanate is pungent, mustard-like, sharp, earthy. Typical uses are condiments, seasonings, savory dishes and snacks.
What did JECFA conclude about isoamyl isothiocyanate?
JECFA evaluated isoamyl isothiocyanate at the 69th meeting in 2008 under JECFA number 1887. The panel concluded: no safety concern at current levels of intake.
Is isoamyl isothiocyanate approved in the EU?
No EU FL number is on file for isoamyl isothiocyanate. It has a JECFA evaluation (JECFA 1887), which the EU list draws on, but the Union List entry itself should be confirmed before EU use.
Can isoamyl isothiocyanate be labeled a natural flavor?
Nature makes isoamyl isothiocyanate, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial isoamyl isothiocyanate, same molecule. The EU and UK follow the same logic without a middle class; Mercosur and Mexico label synthetic isoamyl isothiocyanate identical-to-natural.
Ingredient lookup
Check an ingredient
Start typing to search the ingredient corpus.
Or browse every ingredient page, A to Z.
Guides: What Is FEMA GRAS? · Natural vs artificial · Filing a GRAS notification
Check Isoamyl isothiocyanate in a formula
Screened against FEMA GRAS, 21 CFR and EU rules as you build. Free to start.
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 ISOAMYL ISOTHIOCYANATE under CAS 628-03-5 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.