Polysaccharide and volatile composition of Cabernet wine affected by different over-lees ageing

The influence of different over-lees ageing conditions on the soluble polysaccharides?? glycosyl residue and volatile composition of Cabernet wine was addressed in this work. Specific operating conditions have been considered: wine ageing on fine white lees, wine ageing on fine red lees, wine ageing on fine second-passage white lees and short ageing on rough red lees, which were compared with ageing without lees. The ageing on lees led to an increase in all wine polysaccharide glycosyl residues, with the exception of glucose, xylose and myo-inositol, and to volatile profile modifications. Different behaviours could be observed between the four types of lees, giving important hints for a rational use of them in winemaking. In particular, the use of red grape-derived lees caused the major release of polysaccharides; on the other hand, white grape-derived lees were more effective in enhancing ester content. Second-passage lees did not lead to any increase in wine polysaccharides, whereas they allowed aroma changes, and short ageing on rough red lees caused the greatest adsorption of several volatiles.