The aim of this work was to produce yeast biomass using three different strains of the yeast Saccharomyces cerevisiae and to evaluate the technological properties of the strains by analysing the resulting yeast biomass. If the strains used prove to be good producers of yeast biomass, they would be used for large scale production of yeast biomass outside the laboratory. We used strain ZIM 2113 isolated from must Kraljevina from Dolenjska wine region, strain ZIM 3704 isolated from cider from Carinthia, which metabolizes maltose well and strain of commercial dry yeast of Di-go brand. The strains were propagated to the appropriate concentration in two different liquid media (YPD broth and apple juice), the growth of the cells was monitored during propagation by measuring the optical density and growth curves were obtained. The most intense growth was observed with strain ZIM 3704. Also, when the number of yeast cells was determined using a microscope, the highest value was observed for strain ZIM 3704. This was followed by determination of water content in the produced yeast biomass by drying to constant mass. No major differences were observed in the analysis of yeast biomass of each strain. The technological properties of different yeast strains were evaluated by determining the rising potential. Using the method of measuring the rising time of the dough, the shortest rising time of the dough was measured for the strain of commercial yeast; for the strains ZIM 2113 and ZIM 3704, the measured times were significantly longer.
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