formic acid

sour acid

Found in 427 ingredients across the CompKitchen flavor graph.

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

2D Lewis Structure

Formula: CH2O2
Molecular weight: 46.025 g/mol
PubChem CID: 284 — full record on PubChem

Properties

Odor description: pungent, vinegar, acidic, sour
Odor threshold — orthonasal, in clean water: 450000 ppb 1 published value · see all 6 with sources
Volatility: high
CAS number: 64-18-6
Retention index: 1531

Regulatory · United States

FEMA GRAS — Generally Recognized As Safe for flavoring use

✓ Exact match

FEMA number: 2487
GRAS publication: GRAS 3
FEMA primary name: FORMIC ACID

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.

Acetic, astringent, fruity, mustard, bready, with a pyruvic acid nuance FlavorDB 2.0

372

formyl, pungent, vinegar FlavorDB 2.0

pungent, vinegar, acidic, sour shown above Llm Adjudicated

—

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

6 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

450000 ppb

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

Threshold	Matrix	Source	Paper
450000 ppb	water_odor	Leffingwell	—

In a food matrix

14.0 ppb – 107 ppb

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

Threshold	Matrix	Source	Paper
0.030 ppb	water (food: rice)	Literature corpus	15675786
Flagged: 234× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.
0.070 ppb	water (food: onion)	Literature corpus	15675786, 28331124, 28491071 +6
Flagged: 100× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.
14.0 ppb	water (food: unknown)	Literature corpus	28331124, 28491071, 29983741 +4
107 ppb	water (food: peanut)	Literature corpus	41103313

Retronasal / in-mouth

83000 ppb

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

Threshold	Matrix	Source	Paper
83000 ppb	water_flavor	Leffingwell	—

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 (60.4415 ppb, the engine's canonical value — see the 6 published values). OAV ≥ 1 = perceptible.

Food	Concentration (ppb)	OAV	Source
peanut	525.8	8.70	—
onion	200.0	3.31	—
rice	0.0	0.00	—

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 formic acid. 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 formic acid in it. Full concentrations are in the OAV table above.

388 cmpds

369 cmpds

13 cmpds

27 cmpds