4-methylpentanoic acid
sour acidFound in 100 ingredients across the CompKitchen flavor graph.
Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.
- Formula
- C6H12O2
- Molecular weight
- 116.16 g/mol
- PubChem CID
- 12587 — full record on PubChem
Properties
- Odor description
- cheesy, pungent, sweaty, acidic
- Odor threshold — in air
- 0.400 ppb 1 published value · see all 1 with sources
- Volatility
- high
- CAS number
- 646-07-1
- Retention index
- 14
FEMA GRAS — Generally Recognized As Safe for flavoring use
- FEMA number
- 3463
- GRAS publication
- GRAS 9
- FEMA primary name
- 4-METHYLPENTANOIC ACID
Use-level matrix not extracted for this substance — check the source publication for current ppm guidance.
How this molecule is described
Sources disagree about odour more often than they disagree about chemistry. Rather than show one answer, here is every description on file with how many ingredient records carry it.
Same molecule, unified here — previously counted and displayed as separate compounds.
Ordered by how many independent descriptor streams give each wording, then by how often it appears. The bar is still replication — one source copied onto many ingredients scores high there — so the two can disagree.
Bars are the share of ingredient records carrying each description. High agreement means the sources replicate each other — not necessarily that they are right.
Published thresholds
1 measured value from the literature. Grouped by what was actually measured — a threshold smelled in clean water, tasted in the mouth, or measured in a real food are three different quantities and are not pooled.
In air
0.400 ppbAirborne detection — not comparable to a water threshold.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.400 ppb | air | Nagata 2003 | — |
Only values we can attribute are listed. Where a compendium's licence does not permit public attribution its figures are omitted here, so every number on this page traces to a citable source.
Found in
Measured impact first, then profile shareEvery ingredient known to contain 4-methylpentanoic acid. Ingredients with a measured concentration come first, ranked by odour activity; the rest follow by how large a share of that ingredient's profile this molecule is. The figure beside each is how many different compounds that ingredient has in total — not the concentration of 4-methylpentanoic acid in it.
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