3-Mercapto-2-methylpropanol, an odorous compound recently identified in red
wines, was extracted from a red wine variety, using a low-temperature vacu
um distillation coupled with a specific reversible thiol capture. The analy
sis of the diacetylated wine extract by enantioselective multidimensional g
as chromatography with mass spectrometry detection revealed the presence of
only one enantiomer, (R)-3-mercapto-2-methylpropanol. Although both of the
optical isomers are characterized by the same broth and sweat odour, they
have very different odour thresholds. The amounts of (R)-3-mercapto-2-methy
lpropanol in young Cabernet-Sauvignon and Merlot wines can exceed its perce
ption threshold, thus suggesting its contribution to the aroma of these win
es.