Dynamics of alcoholic fermentation and the quality of white organic wines produced with selected yeasts

The dynamics, duration and specificity of alcoholic fermentation are among the factors determining the quality of white wines. These features depend mostly on technological parameters such as temperature (16°C, 20°C) and amount of total sugars (180 g/dm³, 220 g/dm³). The aim of the current study was to assess the fermentation activity of yeast Saccharomyces cerevisiae from EXCELLENCE® line, intended for production of wines under Organic and National Organic Program (NOP) standards. The used yeasts have a high fermentation activity and are characterized with relatively fast alcoholic fermentation. The result showed that there was no difference in the dynamics of alcoholic fermentation of yeast strains from the used lines. The quick fermentation of sugars was observed in the initial (lag phase) and in the final stage (silent fermentation). However, the experimental variants with different sugar contents completed the process at the same time. A straightforward relationship between the fermentation of sugars and the changes in pH was not observed. According to the mass of the obtained yeast lees, there was a clear difference between all experimental variants. Nevertheless, the mass of the obtained yeast lees for all variants was lower than the normatively allowed. Keywords: yeast, alcoholic fermentation, dynamics, sugars, relative density, pH