trans-2-hexen-1-al

green aldehyde Key food odorant

Found in 1 ingredient across the CompKitchen flavor graph.

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

Key food odorant (individualist)

Dunkel et al. 2014

Identified in the meta-analysis of 227 food samples as one of 151 individualist odorants — appears in <5% of foods, carries the diagnostic signature of specific ingredients. Characteristic odor: green, apple-like.

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

Properties

Odor threshold — orthonasal, in clean water: 17.0 ppb – 110 ppb median 63.5 ppb · 2 published values · see all 2 with sources
CAS number: 6728-26-3
Retention index: 1218

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

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.

Orthonasal, in clean water

17.0 ppb – 110 ppb

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

Threshold	Matrix	Source	Paper
17.0 ppb	water_odor	Leffingwell	—
110 ppb SIDA	water	Dunkel 2014	—

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.

Medium	Median	Range	Values	Papers	Papers agree?
air	25.45 µg/L air	0.0031–429	24	20	no (2.6 decades)
ethanol solution	0.284 ppb	0.284–0.284	1	1	one paper
food matrix	55 ppb	0.0031–1.8e+03	42	35	yes
oil	0.635 ppb	0.3–420	4	4	no (3.1 decades)
unstated	17 ppb	0.0031–1.7e+04	116	86	no (2.3 decades)
water	19.2 ppb	0.017–429	73	63	yes

Found in

Measured impact first, then profile share

Every ingredient known to contain trans-2-hexen-1-al. 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 trans-2-hexen-1-al in it.

pepper

spice

474 cmpds

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