Polysaccharides negative charges attributable

The results in Table 10.2 show an excess of negative charges attributable to tannins and other compounds, such as polysaccharides (Tobiason and Hoff, 1989 Tobiason, 1992 Ferrarini et al., 1995 Vemhet et al., 1995). The surface charge density of red wines is neither proportional to the total phenols nor to the tannin concentration. The differences observed are probably due to grape varieties, the richness of the grapes (polysaccharides) and the wine s state of development. 

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