A biocatalyst was prepared by immobilization of Saccharomyces cerevisiae st
rain AXAZ-1 on apple pieces. It was examined by electron microscope and stu
died during the fermentation of grape must for batch wine-making. The immob
ilized yeast showed an important operational stability without any decrease
of its activity even at low temperatures (1-12 degreesC). Specifically, at
6 degreesC the biocatalyst favored wine production within 8 days, which is
less time than is required for the natural fermentation of grape must. At
1 degreesC wine production was effected in 1 month. This speeding up of the
fermentation could be accepted and adopted by the industry for scaling up
the wine-making process. Total and volatile acidities were similar to those
found in dry wines. The concentrations of higher alcohols (propanol-l and
isobutyl alcohol) were low. The presence of amyl alcohols proved to be temp
erature dependent and decreased with the temperature decrease. The values o
f ethyl acetate concentrations were relatively high, up to 154 mg/L. This p
robably contributes to the fruity aroma and excellent taste of the produced
wines. There was no indication of vinegar odor in the product given that t
he volatile acidity was <0.47 g of acetic acid/L. From the CC-MS analysis i
t was concluded that cell immobilization did not create serious changes in
the product (wine) with regard to the qualitative composition of the aroma
compounds.