nona-2,4-dienal

green aldehyde

Found in 4 ingredients across the CompKitchen flavor graph.

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

Properties

Odor description: fatty
Odor threshold — orthonasal, in clean water: 0.090 ppb – 2.6 ppb median 1.3 ppb · 2 published values · see all 12 with sources
CAS number: 6750-03-4
Retention index: 1672

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

12 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

0.090 ppb – 2.6 ppb

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

Threshold	Matrix	Source	Paper
0.090 ppb	water_odor	Leffingwell	—
2.6 ppb	water/ethanol 6:4 (food: american bourbon whisky)	Literature corpus	—

In a food matrix

0.019 ppb – 0.290 ppb

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

Threshold	Matrix	Source	Paper
0.019 ppb	water (food: longjing green tea infusion)	Literature corpus	—
0.046 ppb	water (food: green tea infusion (jingshan cha))	Literature corpus	—
0.190 ppb	water (food: beef vegetable gravy)	Literature corpus	—
0.190 ppb	water (food: pork vegetable gravy)	Literature corpus	—
0.190 ppb	water (food: reference standard (water))	Literature corpus	—
0.290 ppb	water (food: tea)	Literature corpus	—
27.0 ppb	water (food: milk)	Literature corpus	—
Flagged: 142× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.
67.9 ppb	water (food: rum)	Literature corpus	—
Flagged: 357× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.
81.0 ppb	water (food: beef)	Literature corpus	—
Flagged: 426× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden.

Other matrix

2500 ppb

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

Threshold	Matrix	Source	Paper
2500 ppb	oil (sunflower oil) (food: cocoa beans)	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.

Found in

Measured impact first, then profile share

Every ingredient known to contain nona-2,4-dienal. 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 nona-2,4-dienal in it.

65 cmpds

431 cmpds

438 cmpds

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 nona-2,4-dienal, or compare two ingredients side-by-side.