Differential Analysis of Proteins Involved in Ester Metabolism in two Saccharomyces cerevisiae Strains during the Second Fermentation in Sparkling Wine Elaboration

Abstract

The aromatic metabolites derived from yeast metabolism determine the characteristicsof aroma and taste in wines, so they are considered of great industrial interest. Volatile estersrepresent the most important group and therefore, their presence is extremely important for theflavor profile of the wine. In this work, we use and compare twoSaccharomyces cerevisiaeyeast strains:P29, typical of sparkling wines resulting of second fermentation in a closed bottle; G1, a flor yeastresponsible for the biological aging of Sherry wines. We aimed to analyze and compare the effect ofendogenous CO2overpressure on esters metabolism with the proteins related in these yeast strains, tounderstand the yeast fermentation process in sparkling wines. For this purpose, protein identificationwas carried out using the OFFGEL fractionator and the LTQ Orbitrap, following the detection andquantification of esters with gas chromatograph coupled to flame ionization detector (GC-FID)and stir-bar sorptive extraction, followed by thermal desorption and gas chromatography-massspectrometry (SBSE-TD-GC-MS). Six acetate esters, fourteen ethyl esters, and five proteins involvedin esters metabolism were identified. Moreover, significant correlations were established betweenesters and proteins. Both strains showed similar behavior. According to these results, the use of thisflor yeast may be proposed for the sparkling wine production and enhance the diversity and thetypicity of sparkling wine yeasts.