Î'utochthonous Saccharomyces cerevisiae strains enhance aroma variability and typicity of wines; RNAseq-based transcriptome comparison under winemaking conditions.

This study aimed to isolate indigenous Saccharomyces cerevisiae strains from spontaneous fermentations and assess their effects on the fermentative performance, chemical composition (oenological parameters, organic acids, glycerol, volatile compounds) and organoleptic profiles of wines produced, using two commercial strains serving as control. The gene expression patterns of the isolated yeasts were further explored, employing RNA-seq during fermentation, and linked with the oenological traits. Our study revealed that native strains, supported volatilome, promoting esters and terpenes formation, affecting fruity, floral and sweet attributes and contributing to distinct wine aroma compared to the control ones. Additionally, differences in organic acid and glycerol contents were found among wines. Transcriptomes of the indigenous yeasts identified different genomic responses and explained the variations in metabolites production between strains. In conclusion, the data obtained highlight the importance of understanding yeast's generic backgrounds to achieve promising sensory characteristics in wines, while preserving the identity of a region.