Profound Analysis of the Impact of Indigenous Saccharomyces cerevisiae Strains on the Chemical and Sensorial Profile of Assyrtiko Wine

This study focused on the impact of four indigenous Saccharomyces cerevisiae (S. cerevisiae) strains (S6-A6Y6, S10-A6Y10, S20-A26Y5, and S14-K33Y14) isolated from the Greek terroir on the sensorial profile of Assyrtiko wines. Aroma-active volatiles in the produced wines were identified using gas chromatography-olfactometry/mass spectrometry (GC-O/MS). Additionally, volatile thiols were quantified by GC/MS analysis and results were correlated to descriptive sensory analysis. Wine sensory profiles revealed changes in the perception of tropical nuances and acidity. S. cerevisiae S10-A6Y10 resulted in a more complex profile, while S. cerevisiae S14-K33Y14 introduced smoked wood notes associated with the presence of Furaneol. All strains enhanced volatile thiol production, with 3-sulfanylhexan-1-ol (3SH), its acetate (3SHA), and benzenemethanethiol (BM) exceeding their respective perception thresholds. This study is the first to combine qualitative and quantitative data to differentiate the aromatic fingerprint of Assyrtiko wines solely on the basis of the fermentation inoculum, highlighting the significant influence of indigenous S. cerevisiae strains on the final sensorial profile.