In short
1-Octen-3-one is an unsaturated ketone with a mushroom odour, found in mushrooms. It is extremely potent and used only in traces.
What 1-Octen-3-one smells like
JECFA describes 1-octen-3-one as a colourless liquid with a mushroom odour. Gerard Mosciano's panel (Perfumer & Flavorist, 2001), as The Good Scents Company reproduces it, finds it intense, earthy, metallic and mushroom-like at 0.1%, with vegetative nuances of cabbage and broccoli and minor savoury notes; Wikipedia notes its strong metallic, mushroom-like odour and its part in the smell of metal on skin.
- Leading note
- Mushroom
What makes 1-Octen-3-one distinctive
The smell of mushroom itself, as JECFA describes it, in a single molecule.
How 1-Octen-3-one is used
Its documented use is as a flavouring: JECFA has evaluated it as a flavouring agent, and Sigma-Aldrich sells a food-grade material, diluted in 1-octen-3-ol, noting that it is one of the main volatile flavour compounds of mushroom. In perfumery it is a trace material for mushroom, forest-floor and metallic-skin effects, worked from high dilution because of its strength.
Typical role: modifier (used in small amounts to change the character of a blend).
How 1-Octen-3-one differs from similar materials
- 1-Octen-3-ol
- 1-Octen-3-ol is the alcohol, the rounder mushroom note of fungi; the ketone is more intense and metallic as well as mushroom-like.
Each difference compares the published descriptions of the two materials. Smell varies with grade, supplier and dilution; compare them side by side on blotters before substituting one for another.
Formulation considerations
Extremely potent; work from high dilution.
Identity and classification
- Type
- Aroma chemical
- Origin
- Occurs in nature
- Odour family
- Green
- Note position
- Top to heart note
- Physical form at room temperature
- Liquid
- Also known as
- Amyl vinyl ketone, Oct-1-en-3-one
- CAS number
- 4312-99-6
- Molecular formula
- C8H14O
- Molecular weight
- 126.2 g/mol
- IUPAC name
- oct-1-en-3-one
The CAS number, formula and molecular weight are taken from PubChem compound 61346, whose own record lists this CAS number; checked 24 October 2026.
Safety and compliance
Hazard classification of the neat substance, as PubChem summarises it, read 26 October 2026. Companies notifying the ECHA C&L Inventory classify it (1,594 reports): H302 harmful if swallowed (97.2% of reports). Unless it is harmonised, this is the notifiers' own classification, not a binding one.
This page is general information, not a safety assessment or a specification. Confirm identity, composition, IFRA status and allergen content from your supplier's documents for the lot you hold.
Materials it works with
-
Oakmoss Absolute
Absolute · Chypre / Green — mossy, earthy, inky, forest floor
-
Patchouli Oil
Essential oil · Woody / Chypre — earthy, woody, camphoraceous, dark
-
Vetiver Oil
Essential oil · Woody / Green — earthy, smoky, woody, rooty
Used in formulas and accords
Used in 4 published formulas
1-Octen-3-one is an ingredient in 1 perfume formula and 3 accords in the Formula & Accord Library.
Community formulas
RUŌOD House Originals
Original compositions by RUŌOD House.
Further reading
Questions about 1-Octen-3-one
Is 1-Octen-3-one natural or synthetic?
The molecule occurs in nature. Commercial 1-Octen-3-one may be made by synthesis or obtained from natural sources, so check the supplier's specification if the distinction matters to you.
What is the CAS number of 1-Octen-3-one?
4312-99-6. It was checked against PubChem on 24 October 2026.
Which published formulas use 1-Octen-3-one?
1-Octen-3-one is used in 4 published formulas in the RUŌOD Lab Formula & Accord Library, including Blood Accord, Gardenia Milk and Gasoline Accord. Each is listed with a link under "Used in formulas and accords" on this page.
Sources
- PubChem — compound 61346, checked 24 October 2026.
- PubChem — GHS classification (the ECHA C&L Inventory notifications and any harmonised EU entry), read 26 October 2026.
- PubChem — 1-Octen-3-one (CID 61346): JECFA organoleptic description — odour database.
- The Good Scents Company — 1-octen-3-one (with Mosciano's evaluation) — odour database.
- Wikipedia — Oct-1-en-3-one — published perfumery reference.
- Olfactory profile: the RUŌOD Lab team's synthesis of the published descriptions above, reviewed 26 October 2026. Evidence: more than one published description. Classification and the short description: revision 1. Descriptions of odour are judgement, not measurement.