Resveratrol and other phenolics in white wines from Spain

Abstract

Phenols have antioxidant properties, owed by their phenolic hydroxyls, which seem to be responsible for the physiological effects attributed to moderate wine consumption [5,8]. In red vinification, since the musts are macerated with the skins, red wines have a higher content of phenolic compounds. Nevertheless, the phenolics present in white wines seem to be more active than those in red wines [18]. It is important to profile the phenolic compounds present in white wines responsible for this effect. First, we studied resveratrol and piceid isomers [16], because the trans forms are the major compounds in the root of Polyganum cuspidatum, used in traditional oriental medicine for several purposes, among them the treatment of cardiovascular diseases and cancer. These compounds inhibit LDL oxidation [4], block platelet aggregation [2,13], inhibit eicosanoid synthesis [9,13] and show anticancer activity [6]. Different groups of phenolics are present in white wines [5,17]. Due to the importance of these compounds, we attempted to try to identify and quantify the maximum number of these compounds since any one of them may act as an antioxidant. Besides stilbenes (resveratrol and piceid), the presence of 31 phenolic compounds has been studied in white wines, including phenolic acids, trans and cis hydroxycinnamic acids and derivatives, flavan-3-ols, flavonols, and the oligomeric procyanidins, by HPLC [3]. Here, we report the concentration of stilbenes and phenolics present in white wines.