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