5-Methyl-2-hepten-4-one has a hazelnut, metallic, buttery odor
and a hazelnut, buttery, mushroom taste.
(2E)-5-Methyl-2-hepten-4-one has a fruity, hazelnut, and green odor reminding of dried
fruits and a characteristic, nutty, roasted, and nougat-like hazelnut flavor. It was
identified as the character compound of natural hazelnut flavor. Preparation is possible, for example, by Grignard reaction of 2-butyl magnesium chloride with
crotonaldehyde and subsequent oxidation or by reaction of 2-methylbutanoyl
chloride with propene.
The material is used in fragrances as top-note booster in exotic fruit and citrus
notes and in nut, cocoa, coffee, and so on, flavors.
5-Methyl-2-hepten-4-one has a hazelnut, metallic, buttery odor and a hazelnut, buttery, mushroom taste.
Reported found in roasted hazelnuts and roasted filberts.
Aroma characteristics at 1.0%: sweet roasted hazelnuts, rich nutty with a roasted nut skin.
Taste characteristics at 5 ppm: nutty, roasted, coffee, cocoa, brown with an earthy brown and meaty nuance,
sugar fondant, delicate, hazelnut, with macadamia and pecan nuances
