Impact of Sequential Inoculation with the Non-Saccharomyces T. delbrueckii and M. pulcherrima Combined with Saccharomyces cerevisiae Strains on Chemicals and Sensory Profile of Rose Wines

Controlled inoculations of non-Saccharomyces yeasts are becoming increasingly used to produce high-quality wines due to their enological potential. In this study, we evaluated the impact of sequential inoculation with the commercial non-Saccharomyces yeasts (Torulaspora delbrueckii and Metschnikowia pulcherrima) in combination with Saccharomyces cerevisiae on the chemical and sensory profile of rose wines. Sequential inoculation with T. delbrueckii produced wines with an overall reduction in esters, mainly explained by the lower concentrations of ethyl esters of medium-chain fatty acids and isoamyl acetate. The lower ester concentrations of these wines were related to a reduction in fruity descriptors. An increase was observed, however, in other minor esters such as cinnamates and ethyl esters of branched acids. Zinc, ethyl isobutyrate, and ethyl dihydrocinnamate were selected as potential markers for this fermentation strategy. Sequential inoculation with M. pulcherrima resulted in rose wines with an enhanced ester profile, reduced acetaldehyde, and increased anthocyans and tannins. Compared to the control wines fermented with S. cerevisiae, the changes observed in these wines were far subtler, especially for the volatile profile, sensory characteristics, and color parameters, with isobutyl hexanoate and isoamyl butyrate being selected as potential markers.

Automated summary

Controlled inoculations of non-Saccharomyces yeasts are increasingly used in winemaking for their enological potential. Sequential inoculation with Torulaspora delbrueckii led to a reduction in esters, while Metschnikowia pulcherrima enhanced ester profile in rose wines. Compared to control wines fermented with Saccharomyces cerevisiae, changes in these wines were subtler, with specific compounds identified as potential markers.