RESVERATROL CONTENT OF SOME WINES OBTAINED FROM DRIED VALPOLICELLA GRAPES - RECIOTO AND AMARONE

Resveratrol (trans-3,5,4'-trihydroxystilbene), a phenolic substance pr esent in both grape skin and wines, is a phytoalexin involved in grey mould resistance. A new interest has surfaced in recent years related to the antioxidative actions of resveratrol, which in vivo could be re lated to the prevention of cardiovascular diseases linked to lipid met abolism, particularly HDL production, while the antifungal activity ma y be of interest in wine production technology. These aspects have led to the publication of a number of papers reporting data on the resver atrol content of several kind of wine: for Italian wines, it ranges be tween 0.5 and 10 ppm, depending on cultivar, area of cultivation, clim ate and wine-making technology. In this work, resveratrol was quantifi ed in samples of two unusual Italian wines, Recioto (sweet) and Amaron e (dry), produced with the same cultivar mixture in the same area (Val policella, Verona, Italy) and with the same grape conditioning techniq ue. After resveratrol extraction, reversed-phase HPLC analysis was car ried out and several elution conditions were tested. The resveratrol c ontent of Recioto and Amarone wines was lower than the values reported in the literature for other wines, ranging between 0.05 and 0.8 ppm.