Glycosyl residue composition and polysaccharide families in natural Spanish sparkling wines: the role of grape variety and time of aging in presence and absence of yeast lees

Résumé

Main polysaccharides io wines include polysaccharides rich io arabioose and galactose, rhamnogalacturonans and homogalacturonans from grape berries, but also manooproteins and glucans which are released by yeast during fermentation and duriog ageing on yeast lees. These compounds have an importan! iofluence on the organoleptic properties of sparkling wioes. Consequently, the variables grape variety that the wioes are made from and their agiog time in bottle can affect polysaccharide composition and sensory quality of wines. Therefore, this work addresses to evaluate the role of grape variety and aging in presence and absence of yeast lees on polysaccharide composition of sparkling wines. For this purpose different autochthonous grape varieties from Spain (Verdejo, Viura, Malvasía, Albarín, Godello, Garnacha and Prieto Picudo) were used to elabora te monovarietal sparkling wines. Samples for analysis were taken after 9 and 18 months of agiog on yeast lees in bottle (T9M and Tl8M) and after that 12 months of aging in bottle in absence of yeast lees (T9M+ 12MB and T18M+ 12MB). Glycosyl residue composition and polysaccharide families ofnatural sparkliog wines were determined by GC-MS [1]. Glycosyl residue composition and polysaccharide families allowed a differentiation of wines accordiog to time of aging io bottle in presence and absence of yeast lees. ln general all polysaccharide famílies decreased during the aging io bottle, although the largest decline occurred in absence of yeast lees. Polysaccharide famílies profile was maintained in all samples during the two aging teclmíques. Applyiog the discrimínant analysis, an accurate classification of sparkling wines by grape variety and aging in presence and absence of yeast lees was obtained. As a result, these compounds may play an importan! role, as oenological compounds, to differentiate varietal sparkling wines.