The impact of hybrid yeasts on the aroma profile of cool climate Riesling wines

Abstract The current study highlights the effects of intra- and interspecific hybrid yeasts of the genus Saccharomyces (S.) on the alcoholic fermentation and formation of aroma compounds in cool climate Riesling wines. Three different hybrid yeasts: S. cerevisiae x S. paradoxus (SC x SP), S. cerevisiae x S. kudriavzevii (SC x SK) and S. cerevisiae var. cerevisiae x S. cerevisiae var. bayanus (SC x SB) were investigated. The species S. cerevisiae var. bayanus (SB) was chosen as control variant. It has been demonstrated that the hybrid yeasts have the ability to preserve positive properties while, suppressing undesired properties from the parental yeast species. The hybrid SC x SK showed an increase of desired acetate esters and monoterpenes. The concentrations of higher alcohols were higher in wines fermented by SC x SP, compared to the other variants. SC x SP fermentations resulted in decreased concentrations of L-malate and sulphites.