Description
Menthone has a characteristic odor similar to menthol. May be
prepared by oxidation of menthol.
Chemical Properties
Menthone has a characteristic mint-like odor.
Occurrence
Reported found in severalstereoisomersin nature; l-menthone is a constituent of the essential oils of Russian and
American peppermint, geranium, Andropogon gragrans, Mentha timija and Mentha arvensis; d-menthone is present in the essential
oils of Barosma pulchellum, Nepeta japonica Maxim., and others. d-Isomenthone has been reported isolated from Micromeria abis sinica Benth., Pelargonium tomentosum Jacquin and others; l-isomenthone has been identified in Réunion geranium, Pelargonium
capitau and others. Also reported found in lemon peel oil, black currants, celery seed, cinnamon, peppermint, cornmint, pennyroyal
and other mentha oils, nutmeg, thymus, cocoa, mushrooms, starfruit, coriander leaf, rice, tarragon, calamus, buckwheat, sweet and
bitter fennel, cherimoya, buchu oil, clam and sweet grass oil.
Uses
(±)-Menthone is a Menthol derivative. A volatile flavor compound found in human milk, red and black rice bran and specialty rice types.
Definition
ChEBI: (-)-menthone is a menthone that is cyclohexanone substituted by a methyl and an isopropyl group at positions 5 and 2 respectively (the 2S,5R-stereoisomer). It is an enantiomer of a (+)-menthone.
Preparation
By oxidation of menthol.
Aroma threshold values
Detection: 170 ppb; aroma characteristics at 1.0%: minty, cooling, sweet, refreshing, peppermint fresh,
slightly dirty woody, camphoraceous with a green herbal anise nuance.
Taste threshold values
Taste characteristics at 50 ppm: cooling, peppermint, fresh green, minty, herbal, dirty mentholic with a
refreshing camphoraceous nuance.
Flammability and Explosibility
Notclassified
Metabolism
H?m?l?inen (1912) claimed that menthone was probably oxidized in the rabbit to ketomenthone, since the glucuronide produced was converted by warm dilute H2SO4 to a substance which was probably △4(8 -p-menthen-3-one (pulegone). Williams (1940), however, showed that it underwent reduction in the rabbit with the production of d-neomenthol. The presence of l-menthol, the other possible reduction product, was not detected and it appeared that the biological reduction was asymmetric (Williams, 1959).
