Methoxy-2-methyl-2-butanethiol

Important aroma compounds of black currant berries have been identified mainly by GC-O techniques by Latrasse et al. [119], Mikkelsen and Poll [115] and Varming et al. [7] and those of black currant nectar and juice by Iversen et al. [113]. The most important volatile compounds for black currant berry and juice aroma include esters such as 2-methylbutyl acetate, methyl butanoate, ethyl butanoate and ethyl hexanoate with fruity and sweet notes, nonanal, /I-damascenone and several monoterpenes (a-pinene, 1,8-cineole, linalool, ter-pinen-4-ol and a-terpineol) as well as aliphatic ketones (e.g. l-octen-3-one) and sulfur compounds such as 4-methoxy-2-methyl-butanethiol (Table 7.3, Figs. 7.3, 7.4, 7.6). 4-Methoxy-2-methylbutanethiol has a characteristic catty note and is very important to blackcurrant flavour [119]. 

Methoxy-2-methyl-2-butanethiol [2H3]methoxy Guth and Grosch, 1993c... 

Methoxy-a-tetralone (137), which on formylation at room temperature followed by treatment with n-butanethiol in presence of p-toluenesulfonic acid gave the compound (138), which was converted with lithium dimethylcopper and acetic anhydride to (139). Subjection of (139) to dehydrogenation, hydrolysis and methylation, respectively, yielded (140) which was converted to tetralone (141) by reduction, hydrolysis and methylation of pyralidine enamine. Alkylation of (141) with 2-... 

Methionol (= 3-(Methylthio)-propanol) (thioether alcohol) 4-Methoxy-2-methyl-2-butanethiol (alkyl thiol) Methyl allyl disulfide (alkyl disulfide)... 

Rigaud, J., Etievant, R, Henry, R., Latrasse, A. (1986). Le methoxy-4-methyl-2-butanethiol-2, un constituant majeur de I arome du bourgeon de cassis. Sci. Aliment, 6, 213-220. 

As for the potent odorants in green tea (sen-cha) drinks, the eleven components shown in hgure 17.7 are found to be important contributors to its characteristics. Using the AEDA method, the characteristic sulfur components, such as 4-methoxy-2-methyl-2-butanethiol, 4-mercapto-4-methyl-2-pentanone, and methional, were identihed from the green tea for the first time. Among these eleven components, P-damascenone and methional were reported to increase after the heating process (hgure 17.4), then theorized to have a remarkable effect on the tea drink quality. 

Red currant flavor The flavor of red currants is principally due to ( )-2- hexenal, ( )-2- hexen-l-ol, and hexanal (see alkanals). In black currants the im-pact compound 4-methoxy-2-methyl-2-butanethiol (C6H14OS, Mr 134.24, CAS [94087-83-9]) is responsible for the typical feline note. Terpene compounds such as 1,8- cineole, linalool, a-terpineol (see p-menthenols), citronellol and /S- damascenone, fruit esters (e.g., ethyl butanoate), the butter note of 2,3-butanedione, 4-methoxyacetophenone (CgHmOj, Mr 150.18, CAS [100-06-1]) and 2-isopropyl-3-methoxy-pyrazine (see pyrazines) complete the aroma. In the aroma industry buchu leaf oil is used to generate the black currant note. 

The aroma of natural oils is of special interest. The most important aroma substances of two extra vierge olive oils with different aromas are shown in Table 14.7. In oil I, green, fruity, and fatty notes are predominant while in oil II, the compounds with a green odor are concealed by an aroma substance with a blackcurrant odor, possibly due to a special variety of the olives. The compound involved is the extremely intensive odorant 4-methoxy-2-methyl-2-butanethiol... 

Blackcurrant flavor is very popular in Europe, and is associated with numerous health-related functional foods and with alcoholic drinks (cassis liqueur). The key aroma component in blackcurrant is 2-methoxy-4-methyl-4-butanethiol (18). Characterizing flavors for melons include (Z)-6-nonenal, which contributes a typical melon aroma impression, and (Z,Z)-3,6-nonadienol for watermelon rind aroma impact (22). 2,6-Dimethyl-5-hepten-l-al (MelonaF ) has not been identified in melon, but it provides a melon-like note in compounded flavors (11). The flavor of muskmelons is more complex, with methyl 2-methylbutanoate, Z-3-hexenal, -2-hexenal, and ethyl 2-methylpropanoate identified as the primary, non-characterizing odorants (32). 

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