3-(methylthio)propanal
sulfurous sulfide Key food odorantFound in 388 ingredients across the CompKitchen flavor graph.
Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.
- Formula
- C4H8OS
- Molecular weight
- 104.17 g/mol
- PubChem CID
- 18635 — full record on PubChem
Key food odorant (generalist)
Dunkel et al. 2014Identified in the meta-analysis of 227 food samples as one of 16 generalist odorants — appears in >25% of foods, typically from generic Maillard, lipid-oxidation, or fermentation pathways. Characteristic odor: cooked potato.
Properties
- Odor description
- cooked potato, savory, sulfurous, meaty
- Odor threshold — orthonasal, in clean water
- 0.200 ppb – 1.0 ppb median 0.400 ppb · 3 published values · see all 29 with sources
- Volatility
- high
- CAS number
- 3268-49-3
- Retention index
- 908
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
29 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
0.200 ppb – 1.0 ppbThe reference measurement — smelled in water. OAV is computed against this.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.200 ppb | water_odor | Leffingwell | — |
| 0.400 ppb SIDA | water | Dunkel 2014 | — |
| 1.0 ppb SIDA | water | Rychlik 1998 · 2 studies | — |
In a food matrix
0.090 ppb – 50.0 ppbMeasured in a real food, where the matrix shifts detection — not a clean-water value.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.090 ppb | water (food: rice) | Literature corpus | 41675126 |
| 0.200 ppb SIDA | water (food: hungarian-type salami) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.200 ppb SIDA | water (food: smoked cooked loin (pork)) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.200 ppb SIDA | water (food: extruded wheat flour) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.310 ppb SIDA | water (food: soy sauce) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.430 ppb SIDA | water (food: pink guava) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.430 ppb SIDA | water (food: reference standard (water)) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.430 ppb SIDA | water (food: longjing green tea infusion) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 0.430 ppb SIDA | water (food: coffee) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 1.4 ppb SIDA | water (food: japanese soy sauce) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 1.4 ppb SIDA | water (food: beef vegetable gravy) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 1.4 ppb SIDA | water (food: pork vegetable gravy) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 1.8 ppb SIDA | water (food: hand-squeezed grapefruit juice) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 1.8 ppb SIDA | water (food: litsea pungens fruit) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 5.2 ppb SIDA | water (food: coffee) | Literature corpus | 33714268, 10552650, 19778056 +11 |
| 15.5 ppb | water (food: milk) | Literature corpus | 10552650, 39479676 |
| 35.6 ppb SIDA | water (food: bread) | Literature corpus | 33714268, 28274420, 28490062 |
| 50.0 ppb SIDA | water (food: unknown) | Literature corpus | 33714268, 19778056, 33152860 +2 |
| 907 ppb | water (food: tea) | Literature corpus | 39877541 |
| Flagged: 648× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden. | |||
| 908 ppb | water (food: lime) | Literature corpus | 26213023 |
| Flagged: 649× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden. | |||
Retronasal / in-mouth
5.0 ppbTasted rather than smelled — a different sense, not comparable.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.050 ppb SIDA | oil_retronasal | Rychlik 1998 · 1 studies | — |
| Flagged: 100× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden. | |||
| 5.0 ppb SIDA | water_retronasal | Rychlik 1998 · 2 studies | — |
| 5.0 ppb | water_flavor | Leffingwell | — |
Other matrix
0.050 ppb – 0.520 ppbMeasured in a non-aqueous medium (oil, starch, cellulose).
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.050 ppb SIDA | oil_orthonasal | Rychlik 1998 · 1 studies | — |
| 0.270 ppb SIDA | starch | Rychlik 1998 · 1 studies | — |
| 0.520 ppb SIDA | wine matrix (12% ethanol) (food: red wine) | Literature corpus | 33714268, 10552650, 19778056 +11 |
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 (1.0 ppb, the engine's canonical value — see the 29 published values). OAV ≥ 1 = perceptible.
| Food | Concentration (ppb) | OAV | Source |
|---|---|---|---|
| lime | 908.0 | 908 ⚡ | Corpus paper |
| milk | 725.0 | 725 ⚡ | Corpus paper |
| omelet | 180.0 | 180 ⚡ | Corpus paper |
| coffee | 104.0 | 104 ⚡ | Corpus paper |
| bread | 20.2 | 20.2 ⚡ | Corpus paper |
| tea | 8.5 | 8.49 | Corpus paper |
| soybean sauce | 1.1 | 1.13 | — |
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 3-(methylthio)propanal. 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 3-(methylthio)propanal in it. Full concentrations are in the OAV table above.
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