Localization of S-Cysteine Conjugates in the Berry: Effect of Skin Contact on Aromatic Potential of Vitis vinifera L. cv. Sauvignon blanc Must

Abstract

The localization in the berry of S-cysteine conjugates, sulfur flavor precursors in the Sauvignon blanc grapes, was studied. The assay of the S-cysteine conjugates showed that the content of 4-mercapto-4-methylpentan-2-one and 4-mercapto-4-methylpentan-2-ol precursors (P-4MMP and P-4MMPOH) were equivalent in the juice and skin, while the concentration of 3-mercaptohexan-1-ol precursor (P-3MH) was almost eight times higher in the skin. In comparison with immediate pressing, skin contact only allowed a modest increase in the concentration of P-4MMP and P-4MMPOH, but it enriched the must considerably with P-3MH. The difference in behavior between the P-4MMP and P-4MMPOH and the P-3MH was explained by their localization within the berries.