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phenylacetic acid

sour acid Key food odorant

Found in 422 ingredients across the CompKitchen flavor graph.

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

2D Lewis structure of phenylacetic acid
2D Lewis Structure
Formula
C8H8O2
Molecular weight
136.15 g/mol
PubChem CID
999 — full record on PubChem

Key food odorant (intermediary)

Dunkel et al. 2014

Identified in the meta-analysis of 227 food samples as one of 57 intermediary odorants — appears in 5–25% of foods.

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

Properties

Odor description
honey, floral, sweet, waxy
Odor threshold — orthonasal, in clean water
5500 ppb – 10000 ppb median 7750 ppb · 2 published values · see all 16 with sources
Volatility
high
CAS number
103-82-2
Retention index
2550
Regulatory · United States

FEMA GRAS — Generally Recognized As Safe for flavoring use

✓ Exact match
FEMA number
2878
GRAS publication
GRAS 3
FEMA primary name
PHENYLACETIC 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.

Also filed as
benzeneacetic acid

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.

honey, flower Flavornet Cas, Flavornet Name, FlavorDB 2.0, Flavordb Odor Column 4 sources agree
2
chemical FlavorDB 2.0, Flavordb Odor Column 2 sources agree
1
civet, floral, flower, honey, honeysuckle, sour, sweet, waxy FlavorDB 2.0
406
butter, roasted, chemical, corn FlavorDB 2.0
4
honey-like FlavorDB 2.0
3
honey-like, beeswax-like FlavorDB 2.0
2

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

16 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

5500 ppb – 10000 ppb

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

Threshold Matrix Source Paper
5500 ppb SIDA water Rychlik 1998 · 2 studies —
10000 ppb water_odor Leffingwell —

In a food matrix

1.4 ppb – 6100 ppb

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

Threshold Matrix Source Paper
1.4 ppb water (food: bread) Literature corpus —
1.5 ppb water (food: rice) Literature corpus —
8.1 ppb water (food: unknown) Literature corpus —
28.0 ppb water (food: fish) Literature corpus —
68.0 ppb water (food: green tea infusion (jingshan cha)) Literature corpus —
68.0 ppb water (food: longjing green tea infusion) Literature corpus —
6100 ppb water (food: reference standard (water)) Literature corpus —
12000 ppb water (food: beef vegetable gravy) Literature corpus —
Flagged: 176× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.
12000 ppb water (food: pork vegetable gravy) Literature corpus —
Flagged: 176× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.

Other matrix

26.0 ppb – 360 ppb

Measured in a non-aqueous medium (oil, starch, cellulose).

Threshold Matrix Source Paper
26.0 ppb wine matrix (12% ethanol) (food: red wine) Literature corpus —
150 ppb citrate buffer ph 3.8 (food: orange juice (reconstituted from concentrate)) Literature corpus —
186 ppb oil (sunflower oil) (food: gouda cheese) Literature corpus —
360 ppb oil (sunflower oil) (food: cocoa beans) Literature corpus —
360 ppb oil (sunflower oil) (food: cocoa powder) Literature corpus —

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 (68.0 ppb, the engine's canonical value — see the 16 published values). OAV ≥ 1 = perceptible.

Food Concentration (ppb) OAV Source
milk 4000.0 58.8 ⚡ Corpus paper
red wine 4.0 0.06 Corpus paper

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

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