Influence of cold pre-fermentation treatments on the major volatile compounds of three wine varieties.

The volatile compounds of wines made from three grape varieties (Monastrell, Cabernet Sauvignon and Syrah) using three pre-fermentation techniques (grape freezing, dry-ice and cold maceration) and a control treatment were measured. The different winemaking practices, which are intended to increase the aromatic properties of wines, produced results that depended on the variety concerned. For example, freezing the Cabernet Sauvignon and Syrah grapes produced different results compared with the respective controls, whereas few changes were found on freezing the Monastrell wine. Differences were significant in the case of some volatile compounds. Linear discriminant analysis allowed some grouping of the varieties at sampling but not of the pre-fermentation techniques used.