Effects of Some Yeast on Resveratrol Content During Alcoholic Fermentation

Abstract

The variability of the content of four monomeric forms of resveratrol (3, 5,4’-trihydroxystilbene): trans and cis -resveratrol, , trans and cis -β-Dglucopyranoside in musts of Cagnulari grapes grown in northwest Sardinia, using different strains of the yeast Saccharomyces cerevisiae , was determined by HPLC at different stages of vinification. The first sample was taken after three days, the second 10 days after inoculation of the yeasts and the third after the samples had been stored for two months at 10°C. The data were elaborated by multivariate statistical analysis, considering the variability of the concentrations of the four stilbene forms at different times. The results showed that from the beginning of sampling the form of resveratrol present in the highest amounts was the glucosylated form, but this had already decreased significantly in the second sample. The decrease in the glucosylated forms was not, however, accompanied by a proportional increase in the free forms. In addition, some yeast strains were identified that do not substantially change the total content of the four monomeric forms of resveratol.