3-(methylthio)propionaldehyde

green aldehyde Key food odorant

Found in 423 ingredients across the CompKitchen flavor graph.

Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.

Key food odorant (generalist)

Dunkel et al. 2014

Identified 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.

Source: Angew. Chem. Int. Ed. 2014, 53, 7124–7143

Properties

Odor description: beef, cooked potato, creamy, earthy, fishy, musty, peanut, potato, tomato, vegetable
Odor threshold — orthonasal, in clean water: 0.200 ppb – 1.0 ppb median 0.400 ppb · 3 published values · see all 29 with sources
CAS number: 3268-49-3
Retention index: 1189

Not in FEMA GRAS publications 1-33. Of 3,367 listed flavoring substances, none match this compound name. May still be food-safe under other regulatory routes (FDA 21 CFR 172, EFSA, JECFA) — check femaflavor.org for the authoritative current list.

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.

Also filed as

3-methylthiopropionaldehyde

Same molecule, unified here — previously counted and displayed as separate compounds.

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 ppb

The 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 ppb

Measured 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 ppb

Tasted 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 ppb

Measured 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.

Found in

Measured impact first, then profile share

Every ingredient known to contain 3-(methylthio)propionaldehyde. 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)propionaldehyde in it.

24 cmpds

39 cmpds

52 cmpds

59 cmpds