Nowadays most commonly used starter culture in winemaking is yeast strain Saccharomyces cerevisiae. Its main advantage is ability to complete alcoholic fermentation process without unnecessary halts and formation of unwanted fermentation products. However, it is becoming more and more interesting to use other non-Saccharomyces yeast strains of genera Hanseniaspora, Pichia, Starmerella, Torulaspora, Meschnikowia, Lachancea, forming numerous secondary metabolic products that improve wine’s quality and complexity. Aforementioned strains are also interesting for the production of less alcohol-rich wines. In order to avoid stuck or sluggish fermentations, we studied impact of addition of various non-Saccharomyces yeast strains in combination with S. cerevisiae on the course of alcoholic fermentation of must and many characteristics of thus produced young wines (technological, aromatic, metabolic characteristics). We used commercially available starter cultures of non-Saccharomyces yeast strains, known by their commercial names Biodiva (Torulaspora delbrueckii), Laktia (Lachancea thermotolerans), and Flavia (Metschnikowia pulcherrima). Wines produced in such manner had a more complex aromatic profile due to a more pronounced varietal aroma and presence of many esters and higher alcohols. Samples contained an average of 7,64 g/L glycerol (literature ranges of glycerol content between 5 and 14 g/L). As expected the wine sample fermented by lactic acid producing Laktia starter, had lower pH value (3.3) and higher total acidity that other samples, but received lowest scores according to Buxbauman method of sensory analysis. As the sole sample, it was categorized to the table wine category with the geographical indication or regional wine with protected geographical indication (PGI). The rest of the wine samples were categorized as quality wines with protected geographical origin (PGO). There were no halts during fermentation process. We have also noted that wine samples, in which yeast strain S. cerevisiae was added later, completed the process faster and at higher fermentation rate.
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