The master thesis aimed to verify the influence of inoculation of must with
Hanseniaspora yeasts on the kinetics of alcoholic fermentation and the sensory
characteristics of the resulting wine. Since non-Saccharomyces yeasts cannot complete
alcoholic fermentation, we added S. cerevisiae to complete the process. The
experiment used two yeast species of the genus Hanseniaspora (H. uvarum and H.
opuntiae) isolated from two different locations. The Hanseniaspora species were. H.
uvarum (HU) was isolated from the Podravje wine region and H. opuntiae (HO) from
the natural environment of Hawaii. The yeasts were inoculated into must Welsh
Riesling, vintage 2019, from the Podravje winegrowing region. S. cerevisiae was
added to the must samples inoculated with different cell concentrations of
Hanseniaspora yeasts (10, 100, 1000 cells/mL) after 24 hours or after 72 hours
depending on the set scheme that carried out the fermentation until the end, and during
the addition, we also change the temperature in the incubator. The process was
monitored gravimetrically and the mass of each fermenter was measured daily. After
the alcoholic fermentation, wine samples were sent for physicochemical analysis using
WineScanTM. We also performed a sensory evaluation, where we found that the wine
sample with the addition of HO yeast tasted the best. The wine into which we
inoculated the yeast H. opuntiae had the most dominant descriptor fruity, followed by
flowers and honey. Samples with inoculated yeast H. opuntiae and a concentration of
1000 cells/mL had a more harmonious, fuller taste and flavour, and a more pleasant
aroma, as expected. The wine yeasts H. uvarum at a concentration of 1000 cells/mL
showed faster fermentation kinetics and adaptation to the must.
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