In recent years, non-Saccharomyces yeasts are frequently used for wine fermentation in addition to Saccharomyces yeasts, which can have a positive effect on wine quality, especially wine aroma, if properly inoculated. In this work, we investigated how sequential inoculation can affect the course of fermentation of white must (Welschriesling variety, 2019 vintage). We inoculated two samples with non-Saccharomyces yeast only under the trade name Gaïa, species Metscnikowia fructicola; after three days, we then sequentially inoculated four samples with Saccharomyces yeast - two with S. cerevisiae and two with S. bayanus. The progress of fermentation was monitored gravimetrically. Fermentation with non-Saccharomyces yeast only did not come to an end and fermented more slowly than the sequentially inoculated samples. Differences in fermentation kinetics were observed between the different Saccharomyces yeast strains. Upon completion of fermentation, we also performed sensory analyses of the wines using three different methods: Flash profiling method (in which the sample sequentially fermented with S. bayanus obtained the best score). In the CATA method ("check all that apply"), the most frequent descriptors were aroma of medium intensity, fruity and apples. On the nine-point hedonic scale, the non-Saccharomyces yeast samples were the most likeable.
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