DEVELOPMENT OF A METHOD FOR ANALYZING THE VOLATILE THIOLS INVOLVED INTHE CHARACTERISTIC AROMA OF WINES MADE FROM VITIS-VINIFERA L. CV SAUVIGNON BLANC

Volatile thiols were purified from a dichloromethane extract of Sauvig non blanc wine by the reversible combination of the thiols with. p-hyd roxymercuribenzoate, fixation of the resulting complex in an anion exc hange column, and finally release of the thiols with cysteine. By anal yzing the purified thief. extract from 500 mL of wine, using gas chrom atography coupled with mass spectrometry, it was possible to measure t he concentrations of five volatile compounds at once: 4-mercapto-4-met hylpentan-2-one, 3-mercaptohexyl acetate, 3-mercaptohexan-1-ol, 4-merc apto-4-methylpentan-2-ol, and 3-mercapto-3-methylbutan-1-ol. Analysis of 10 typical Sauvignon Blanc nines (Bordeaux, Sancerre) showed that t he first three compounds listed above are expected to be involved in v arietal aroma, as they may be present at concentrations greatly in exc ess of their respective perception thresholds.