alpha-ionone
floral ketoneFound in 46 ingredients across the CompKitchen flavor graph.
Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.
- Formula
- C13H20O
- Molecular weight
- 192.30 g/mol
- PubChem CID
- 5282108 — full record on PubChem
Properties
- Odor description
- violet, fruity, woody
- Odor threshold — orthonasal, in clean water
- 2.7 ppb 1 published value · see all 4 with sources
- Volatility
- medium
- CAS number
- 127-41-3
- Retention index
- 71
FEMA GRAS — Generally Recognized As Safe for flavoring use
- FEMA number
- 4144
- GRAS publication
- GRAS 22
- FEMA primary name
- beta-Ionone epoxide
Reported use levels (ppm by food category)
Typical vs maximum reported addition levels in finished food. Use as a regulatory ceiling reference — verify against the current GRAS publication for your product category.
| Food category | Typical (ppm) | Maximum (ppm) |
|---|---|---|
| baked goods | 3 | 15 |
| breakfast cereal | 2 | 10 |
| cheese | 2 | 10 |
| condiments/ relishes | 5 | 25 |
| egg products | 2 | 10 |
| fats/oils | 2 | 10 |
| fish products | 3 | 15 |
| frozen dairy | 5 | 25 |
| fruit ices | 1 | 5 |
| other grains | 3 | 15 |
| processed fruits | 1 | 5 |
| soft candy | 2 | 10 |
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.
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
4 measured values 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.
Orthonasal, in clean water
2.7 ppbThe reference measurement — smelled in water. OAV is computed against this.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 2.7 ppb SIDA | water | Rychlik 1998 · 2 studies | — |
In a food matrix
0.660 ppb – 5.0 ppbMeasured in a real food, where the matrix shifts detection — not a clean-water value.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.660 ppb | water (food: tomato) | Literature corpus | 29086819 |
| 5.0 ppb | water (food: soy sauce) | Literature corpus | 29086819 |
| 784 ppb | water (food: unknown) | Literature corpus | 29086819 |
| Flagged: 157× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden. | |||
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.
Where you'd actually smell it
Odor Activity Value = measured concentration ÷ odor threshold (2.7 ppb, the engine's canonical value — see the 4 published values). OAV ≥ 1 = perceptible.
| Food | Concentration (ppb) | OAV | Source |
|---|---|---|---|
| tomato | 0.9 | 0.34 | Corpus paper |
| soybean sauce | 0.1 | 0.04 | — |
Concentrations from PubMed Central Open Access papers (free literature corpus, MIT-style licensed). Copper = OAV ≥ 10 (strongly perceptible). Green = OAV ≥ 1 (perceptible).
Found in
Measured impact first, then profile shareEvery ingredient known to contain alpha-ionone. 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 alpha-ionone in it. Full concentrations are in the OAV table above.
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