INTERACTIONS BETWEEN TOXIC FATTY-ACIDS FOR YEASTS AND COLLOIDS, CELLULOSE AND YEAST GHOST USING THE EQUILIBRIUM DIALYSIS METHOD IN A MODEL WINE SYSTEM

The capacity of different materials (yeast walls, colloids and cellulo se) to bind octanoic acid and decanoic acid was investigated in a mode l wine. The interactions between these toxic fatty acids and the solub le or insoluble material was shown using the equilibrium dialysis meth od. Yeast walls adsorb decanoic acid and to a lesser extent octanoic a cid which confirms previous results. In comparison, colloids from both grape or yeast weakly bind decanoic acid and do not significantly bin d octanoic acid. No interactions between cellulose and fatty acid were observed. According to the yeast wall composition, lipids seem to pla y a key role for binding. With regards to our results, the effect of c olloids on fermentation rate and malolactic activity is discussed.