Application technologique d'un lysat industriel de levure à la stabilisation tartrique et protéique des vins blancs

Polysaccharides play an important role in wine stability, due to their ability to take part in colloidal equilibrium ; addition of yeast derivative products are a novel rapid way to enrich colloidal structure of white wines and to increase their stability. Different amounts of an industrial formulate made by thermal lysis of yeast cell walls, and their effects on tartaric and protein stability were evaluated for three white wines, fifteen days and ten months after bottling. The lysate had some good stabilizing properties in the short period, but it determined a loss in stability of wines in long storage conditions (both tartaric and protein) ; this effect was strongly affected by dosage. A possible explanation could be linked to interactions between colloidal particles determining an increase in their size during storage time ; the consequent precipitation phenomena could determine a loss in stabilizing factors of wines during bottle storage ; this effect seemed to be emphasized by the added lysat