Wine is a product of the alcoholic fermentation of must, in which yeasts play a major role. The start of fermentation can be a spontaneous process or we can use commercial starters. In order to understand the influence of certain strains on the sensory profile of wine, it is important to be able to determine their presence, type and concentration on grapes, synthetic must and wine and to monitor their dynamics during alcoholic fermentation. The aim of the thesis was to select a typing method that will enable the tracing of autochthonous strains of wine yeasts during wine fermentation and the determination of their impact on wine quality. In the thesis, we tested two methods for distinguishing between strains. The first was the PCR analysis of interdelta regions, with which we tested the ability to distinguish between commercial wine strains. However, this method proved to be inappropriate due to its non-repeatability and unreliability. Secondly, we used the method of analysis of microsatellite sequences of wine strains, which in most cases (5/7) was able to distinguish between strains of indigenous wine yeasts. To evaluate the method, the stability of microsatellites during fermentation was checked. Fermentation was performed in synthetic must with autochthonous strains, where we monitored its dynamics, microbial growth and dynamics in the relationship between strains from different wine growing regions by analysing microsatellites. By analysing microsatellite sequences, we wanted to predict phenotypic traits of the strains, which we were unable to do so, as it turned out that the most genetically related strains were phenotypically different. Finally, we determined the chemical composition of the synthetic wine.
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