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caffeine

other nitrogen compound

Found in 542 ingredients across the CompKitchen flavor graph.

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

2D Lewis structure of caffeine
2D Lewis Structure
Formula
C8H10N4O2
Molecular weight
194.19 g/mol
PubChem CID
2519 — full record on PubChem

Properties

Odor description
odorless, bitter
Odor threshold — in a food matrix
4.0 ppb – 952 ppb median 478 ppb · 2 published values · see all 2 with sources
Volatility
medium
CAS number
58-08-2
Retention index
2077
Regulatory · United States

FEMA GRAS — Generally Recognized As Safe for flavoring use

✓ Exact match
FEMA number
2224
GRAS publication
GRAS 3
FEMA primary name
CAFFEINE

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.

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.

astringent FlavorDB 2.0
590
bitter, odorless FlavorDB 2.0
1
bitter FlavorDB 2.0
1
odorless, bitter shown above Llm Adjudicated
—
odorless Flavordb Odor Column
—

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.

In a food matrix

4.0 ppb – 952 ppb

Measured in a real food, where the matrix shifts detection — not a clean-water value.

Threshold Matrix Source Paper
4.0 ppb water (food: unknown) Literature corpus 27247775, 28303785, 39458696 +1
952 ppb water (food: tea) Literature corpus 33152893, 41617902

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 (477.785 ppb, the engine's canonical value — see the 2 published values). OAV ≥ 1 = perceptible.

Food Concentration (ppb) OAV Source
tea 28.7 0.06 —

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 caffeine. 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 caffeine in it. Full concentrations are in the OAV table above.

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