Key odorant · the claim says “primary odorants of wheat bread crust”
A review of bread aroma chemistry reports 2-acetyl-1-pyrroline, (E)-2-nonenal, 3-methylbutanal, 2,3-butanedione, methional and (Z)-2-nonenal as primary odorants of wheat bread crust, with 2-acetyl-1-pyrroline suggested as the key crust odorant behind its cracker-like note; the crumb has a different set, and these odorants are generated mainly during baking.
Scope: Wheat bread; crust and crumb differ, and odorants depend on ingredients, fermentation and baking. CLM-BREAD-001 ↗
Linked to the odour · the claim says “potent odorants”
Aroma extract dilution analysis identified 39 potent odorants in Cheddar cheese; compounds such as acetic and butanoic acids, dimethyl trisulfide, methional and 1-octen-3-one differed most between cheeses ripened for different times.
Scope: Cheddar ripened for 6 to 14 months; cheese aroma varies widely between cheese types. CLM-CHEDDAR-001 ↗
Linked to the odour · the claim says “may be partly responsible for typical popcorn aroma”
A comparison of popped popcorn hybrids suggested that volatiles including 2-furfurylthiol, methional, 4-vinylguaiacol, 2-pentylfuran, guaiacol and 2-acetylpyrrole may be partly responsible for typical popcorn aroma.
Scope: Six hot-air-popped hybrids; the links are correlations stated tentatively by the authors, without olfactometry. CLM-POPCORN-001 ↗
Checked against PubChem and Wikidata on 2026-10-02 (identifier check run 37063263965). Every name SmellBook uses must resolve to the same single PubChem compound.
WHAT THIS MEANS
SmellBook lists a molecule only where a VERIFIED claim names it, in the role and scope that claim states. A molecule reported in a smell's evidence is not the whole smell: most smells come from many compounds together, and the studies measured particular samples, such as one cultivar, an essential oil or a cooked product.