2-acetylthiazole

sulfurous thiazole

Found in 29 ingredients across the CompKitchen flavor graph.

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

2D Lewis Structure

Formula: C5H5NOS
Molecular weight: 127.17 g/mol
PubChem CID: 520108 — full record on PubChem

Properties

Odor description: roast, nut, sulfur
Odor threshold — orthonasal, in clean water: 10.0 ppb 1 published value · see all 3 with sources
Volatility: high
CAS number: 24295-03-2
Retention index: 1020

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.

Descriptions on file

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.

roast, nut, sulfur shown above Flavornet Cas

—

chocolate, hazelnut, nut, nutty, popcorn, roast, roasted peanuts, sulfur FlavorDB 2.0

roast, nut, sulfur, chocolate, hazelnut, nutty, popcorn, roasted peanuts FlavorDB 2.0

nutty, roasted FlavorDB 2.0

baked, rice, grain FlavorDB 2.0

roasted, rich FlavorDB 2.0

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

3 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

10.0 ppb

The reference measurement — smelled in water. OAV is computed against this.

Threshold	Matrix	Source	Paper
10.0 ppb SIDA	water	Rychlik 1998 · 1 studies	—

Retronasal / in-mouth

10.0 ppb

Tasted rather than smelled — a different sense, not comparable.

Threshold	Matrix	Source	Paper
10.0 ppb	water_flavor	Leffingwell	—
10.0 ppb SIDA	water_retronasal	Rychlik 1998 · 1 studies	—

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 (10.0 ppb, the engine's canonical value — see the 3 published values). OAV ≥ 1 = perceptible.

Food	Concentration (ppb)	OAV	Source
rice	10.0	1.00	Corpus paper
lard	0.4	0.04	PMID 25036492

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 share

Every ingredient known to contain 2-acetylthiazole. 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 2-acetylthiazole in it. Full concentrations are in the OAV table above.

432 cmpds

✓1 13 cmpds

28 cmpds

54 cmpds