Several main wine polysaccharides, isolated from a red wine and characterized in terms of composition and structural organization, have been microfiltered separately in a colloid-free synthetic wine to determine their respective incidence on the permeation fluxes of an hydrophilic organic microfiltration membrane. Most wine polysaccharides induced a significant decrease of the permeation flux density. The permeation flux decline were concentration-dependent and differed according to the nature and the composition of the polysaccharide tested. The hydrodynamic volume seemed to play a major role in determining the reduction of membrane permeability. Considering the mean amounts of the different polysaccharides in wines, it appeared that yeast mannoproteins displayed the strongest incidence on wine filtrability for the considered membrane. However, microfiltration experiments performed with a mixture of all polysaccharides tested pointed out that the pectic polysaccharides had a protective effect against the flux decrease induced by mannoproteins. The flux decline related to polysaccharides during wine microfiltration appears then to depend more on the respective amounts of the different polysaccharides than on the total polysaccharide content.
- hydrophilic membrane
- pectic polysaccharides
- Copyright 1999 by the American Society for Enology and Viticulture