Comparative Analysis of Concentrations of trans-and cis-Resveratrol in Must and Wine from Eleven Different Grapevines Grown in Hokkaido, Northern Japan

Abstract

It has been suggested that resveratrol (RT) has a protective effect against cardiovascular diseases. We analyzed the concentration of RT in must and wine samples made from nine varieties of red and two of white grapes grown in Hokkaido, Japan, by a combination of normal and reverse phase high-performance liquid chromatography. The sum of trans-and cis-RT concentrations in the must differed significantly among the grapes, ranging from 0.04 to 0.41 mg/L. After alcoholic fermentation, the RT concentrations in the red wines increased to 0.50∼2.76 mg/L due to maceration with skin, but those in the white ones scarcely changed. The ratios of trans-RT to the cis-form in the must samples were in the range of 3.0 to 12.0, but an increasing level of cis-RT was usually observed in the wine samples. In red wine samples, after malolactic fermentation, the RT concentrations were found to be increased 1.1-to 1.9-fold compared with those measured at the end of alcoholic fermentation. In contrast, the amounts of piceid (RT glucoside), quantified as the RT equivalent after β-glucosidase digestion, decreased in the wines. It was therefore assumed that the increase in RT might have resulted from the hydrolysis of piceid during malolactic fermentation.