Some clues about the changes in wine aroma composition associated to the maturation of "neutral" grapes.

This paper presents a study of the influence of the harvesting date on concentrations of odorants in Moristel wines of two vintages. The wine made from grapes harvested early facilitated the accumulation of acetaldehyde (associated with low polyphenols concentrations) and higher concentrations of branched acids. A reason for these greater levels could be the lack of reduction factors (NADH or NADPH).

Influence of viticulture practices on grape aroma precursors and their relation with wine aroma.

Background: The effects of two different operations in the vineyard (basal leaf plucking and head trimming) on the synthesis of aromatic precursors in the grape and their impact on wine aroma have been studied and compared with a control sample. The study was carried out over two consecutive years with four different varieties. Glycosidic precursors were analysed in grapes and volatile compounds were studied in the wines.