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isopentanoic acid

dairy acid

Found in 1 ingredient across the CompKitchen flavor graph.

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

Properties

Odor threshold — orthonasal, in clean water
410 ppb – 700 ppb median 555 ppb · 2 published values · see all 21 with sources
CAS number
503-74-2
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.

Published thresholds

21 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

410 ppb – 700 ppb

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

Threshold Matrix Source Paper
410 ppb water_odor Leffingwell —
700 ppb SIDA water Rychlik 1998 · 5 studies —

In a food matrix

12.0 ppb – 1200 ppb

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

Threshold Matrix Source Paper
12.0 ppb water (food: goat milk) Literature corpus 19753606, 28331124, 36337648 +4
100 ppb water (food: litsea pungens fruit) Literature corpus 19753606, 28331124, 36337648 +4
250 ppb water (food: longjing green tea infusion) Literature corpus 19753606, 28331124, 36337648 +4
490 ppb water (food: reference standard (water)) Literature corpus 19753606, 28331124, 36337648 +4
1200 ppb water (food: japanese soy sauce) Literature corpus 19753606, 28331124, 36337648 +4
1200 ppb water (food: beef vegetable gravy) Literature corpus 19753606, 28331124, 36337648 +4
1200 ppb water (food: pork vegetable gravy) Literature corpus 19753606, 28331124, 36337648 +4

Retronasal / in-mouth

26.0 ppb – 750 ppb

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

Threshold Matrix Source Paper
26.0 ppb SIDA oil_retronasal Rychlik 1998 · 1 studies —
750 ppb SIDA water_retronasal Rychlik 1998 · 1 studies —

In air

0.078 ppb

Airborne detection — not comparable to a water threshold.

Threshold Matrix Source Paper
0.078 ppb air Nagata 2003 —

Other matrix

6.0 ppb – 250 ppb

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

Threshold Matrix Source Paper
6.0 ppb SIDA starch Rychlik 1998 · 1 studies —
22.0 ppb SIDA oil_orthonasal Rychlik 1998 · 1 studies —
22.0 ppb oil (sunflower oil) (food: gouda cheese) Literature corpus 19753606, 28331124, 36337648 +4
22.0 ppb oil (sunflower oil) (food: cocoa beans) Literature corpus 19753606, 28331124, 36337648 +4
22.0 ppb oil (sunflower oil) (food: cocoa powder) Literature corpus 19753606, 28331124, 36337648 +4
78.0 ppb ethanol/water (food: rum / red wine) Literature corpus 19753606, 28331124, 36337648 +4
78.0 ppb ethanol/water 40/60 (food: rum (aged)) Literature corpus 19753606, 28331124, 36337648 +4
120 ppb wine matrix (12% ethanol) (food: rum / red wine) Literature corpus 19753606, 28331124, 36337648 +4
250 ppb SIDA cellulose 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.

Thresholds in published tables

Numbers printed in open-access papers, grouped by the medium the table states. Median and full range of the values; “agree” means two or more papers whose middle 80% of values sit within 100×. Not reviewed.

MediumMedianRangeValuesPapersPapers agree?
air 490 µg/L air 0.0018–3.91e+03 1210 no (6.3 decades)
ethanol solution 1045 ppb 8–2.83e+04 1513 no (2.5 decades)
food matrix 250 ppb 0.54–1.3e+05 4736 no (2.3 decades)
model wine or beer 33 ppb 33–33 11 one paper
not applicable 33 ppb 33–33 11 one paper
oil 22 ppb 9–320 43 yes
starch or other 6 ppb 5.5–24 33 yes
unstated 137.2 ppb 0.05–5e+04 7868 no (2.1 decades)
water 490 ppb 1.3–1.8e+03 3028 yes

Found in

Measured impact first, then profile share

Every ingredient known to contain isopentanoic 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 isopentanoic acid in it.

wine
beverage alcoholic
565 cmpds
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