COMPARISON OF ETHANOL TOLERANCE OF FREE AND IMMOBILIZED SACCHAROMYCES-UVARUM YEASTS

O-2 consumption and CO2 production of free and immobilized Saccharomyc es uvarum in the presence of ethanol were compared. The protective eff ect of immobilization on the yeast ethanol tolerance at 5-20 % of etha nol was more evident in CO2 production than in O-2 consumption. CO2 pr oduction by the yeast immobilized in calcium alginate and calcium pect ate gel beads was approximately 2.5-times higher than by the free yeas t at 5 and 10 % of ethanol. 4-Fold increase of CO2 production was obse rved at 15 % ethanol. Immobilization in calcium-containing carriers (a lginate, pectate) resulted in enhanced activities of yeasts compared t o the kappa-carrageenan carrier.