EFFECT OF IMMOBILIZED YEASTS ON THE QUALITY OF BOTTLE-FERMENTED SPARKLING WINE

To eliminate the difficult clarification process in bottle fermented s parkling wine production, four variations of Ca-alginate entrapment te chnique were applied for immobilization of a Saccharomyces bayanus sta rter strain. Biocatalyzer prepared on the usual way of Ca-alginate ent rapment technique (A) was compared to that prepared by coating the alg inate beads with a cell-free alginate layer (B). Both types of biocata lyzers were investigated in two levels of cell loading (1, 2) and comp ared to the traditional free-cell fermentation (K) as a control. Chemi cal analysis of sparkling wines after three months of aging on yeast s howed little differences only in few parameters. The organoleptic qual ity of sparkling wines was not adversely affected by either types of b iocatalyzers. The cell retention capacity of biocatalyzers characteriz ed by the limpidity of sparkling wine was not satisfactory using bioca talyzer without coating. A significantly better cell retention could b e achieved by the use of cell-free alginate coating, but the adhesion of the coat to the surface of the beads needs further improvement.