Application of NMR for the assessment of physiological and sensorial performances of Saccharomyces cerevisiae strains as candidate starters for the production of sparkling wine

The autolysis of yeasts cells in sparkling wines production has a key role for foam formation, wine stability and aroma composition. The present research was focused on the application of NMR spectroscopy on a group of isolated Saccharomyces cerevisiae strains to compare their autolysis patterns and select the most promising candidates as sparkling wine starters. The strains clustered in three groups with different autolysis profiles, comprising compounds reported to play significant roles in foam quality, aroma, mouthfeel, taste and cell stress protection, such as nucleotides, amino acids and cyto-protective molecules like myo-inositol and choline. Seven strains were then selected and characterized by sensory analysis. Correlation analysis linked autolysis metabolites to sensory traits, including odor and in-mouth descriptors, as well as foam properties. The strains were grouped in four couples with differing technological potential, showing varying potential for foam stabilization (higher levels of choline and myo-inositol), odor complexity and fineness (higher levels of nucleotides), in mouth persistence (related to myo-inositol), odor intensity (correlated with the levels of uridine and tyrosine). NMR analysis showed to be an application to monitor autolysis markers being a powerful tool to select starter strains for in sparkling wines production.