Skip to main content

2,4,5-trimethylthiazole

sulfurous thiazole

Found in 16 ingredients across the CompKitchen flavor graph.

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

2D Lewis structure of 2,4,5-trimethylthiazole
2D Lewis Structure
Formula
C6H9NS
Molecular weight
127.21 g/mol
PubChem CID
61653 — full record on PubChem

Properties

Odor description
earth
Odor threshold — orthonasal, in clean water
50.0 ppb 2 published values · see all 2 with sources
Volatility
high
CAS number
13623-11-5
Retention index
1387
Regulatory · United States

FEMA GRAS — Generally Recognized As Safe for flavoring use

✓ Exact match
FEMA number
3325
GRAS publication
GRAS 5
FEMA primary name
2,4,5-Trimethylthiazole

Use-level matrix not extracted for this substance — check the source publication for current ppm guidance.

Source: FEMA GRAS publications 1-33.

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
2,4,5-trimethyl-thiazole

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

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.

earth shown above Flavornet Cas
—
chocolate, cocoa, coffee, earth, hazelnut, musty, nutty, vegetable FlavorDB 2.0
14

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

2 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

50.0 ppb

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

Threshold Matrix Source Paper
50.0 ppb water_odor Leffingwell —
50.0 ppb SIDA water 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.

Found in

Measured impact first, then profile share

Every ingredient known to contain 2,4,5-trimethylthiazole. 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 2,4,5-trimethylthiazole in it.

See all 16 ingredients with Pro

The inverted compound index is a Pro feature — reverse-search any of 5,240 flavor molecules across the full graph.

Into the chemistry?

Get a molecule-level pairing breakdown each week — which ingredients share a compound, and why it matters at the table. Free, no spam.

Prefer an account? Create a free account to save pairings and unlock the full chemistry.

Try the pairing tools to see which ingredient combinations rely on 2,4,5-trimethylthiazole, or compare two ingredients side-by-side.