Octen mushroom aroma

Uq 1.4378, may occur in the optically active form. It is found, for example, in lavender oil and is a steam-volatile component of mushrooms. l-Octen-3-ol is a liquid with an intense mushroom, forest-earthy odor that can be prepared by a Grignard reaction from vinylmagnesium bromide and hexanal. It is used in lavender compositions and in mushroom aromas. 

Some of the carbonyl compounds and alcohols form important aroma components in various foods. l-Octene-3-one and l-octene-3-ol are the main components of fresh mushroom aromas. From the series of aldehydes, 2-heptenal to 2-decenal are found in potato chips, and 2-nonenal forms an important component of the aroma in carrots. 

Aroma substances are formed by the enzymatic oxidative degradation of the highly unsaturated fatty acids with the participation of lipoxygenases of varying specificity. These aroma substances contribute to the iruld green-metaUic-mushroom aroma of fresh fish. Dilution analyses have shown that these substances are acetaldehyde, propanal, l-octen-3-one, (Z)-l,5-octadien-3-one, (E,Z)-2,6-nonadienal, (Z,Z)-3,6-nonadienal and (E,E)-2,4-decadienal. 

Aroma impact compounds that are universal to all varieties of mushrooms include l-octen-3-ol (1 ppb threshold) and l-octen-3-one (0.05 ppb threshold), both of which have been described as having a fresh, wild-mushroom aroma (15). However, l-octen-3-one also possesses a metallic odor, particularly in the context of oxidized oils (34). 

Among the odorants listed in Table 6.33, l-octen-3-ol (no. 4), the character impact aroma compound of mushrooms [62], is also responsible for the characteristic mush-room-like note of camembert, which is intensified by l-octen-3-one (no. 5). Although the concentration of this ketone is much lower than that of the alcohol, it can be aroma-active in cheese because its odour threshold is 100 times lower than that of the alcohol [60], Methanethiol, methional, dimethylsulphide, dimethyl trisulphide and methylene-bis(methylsulphide) generate the sulphurous odour note, whereas phenyle-thyl acetate is responsible for the floral odour note [61 ]. 

Ney, K.H. and Freytag W.G. (1978) Aroma of mushrooms. Sensory properties of l-octen-3-ol structural analogues. Gordian 78, 144-6 (Chem. Abstr. 89, 174437a). 

Another unusual component Is the potent odorant l-octen-3-one which has been reported to have a mushroom-metallic aroma and has been found in cooked mushroom ( 5) and artichoke ( ). 

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