Effects of co-fermentation with Lachancea thermotolerans or Metschnikowia pulcherrima on concentration of aroma compounds in Pinot Blanc wine

Slovakian strains of Lachancea thermotolerans and Metschnikowia pulcherrima were used in sequential co-fermentation with Saccharomyces cerevisiae in small-scale production of Pinot Blanc wine from the Small Carpathian wine region in Slovakia. Aroma compounds of the produced wines were analysed using solid-phase microextraction coupled to gas chromatography-mass spectrometry. Thirty-six aroma compounds were quantified, demonstrating no significant differences in concentrations of almost half of them, including acetic acid, ethyl acetate, 2,3-butanediol and butanoic acid. Wines produced with non-Saccharomyces yeasts did not contain increased concentrations of aroma-active esters, but contained increased concentrations of methionol and decreased concentrations of furfural. Wine produced with L. thermotolerans contained increased concentrations of 2-phenylethanol, diethyl succinate and phenylethyl acetate, together with an increased concentration of 3-methylbutanoic acid. Wine produced with M. pulcherrima contained increased concentrations of 2-phenylethanol and diethyl succinate, together with a decreased concentration of acetaldehyde. Results of the study demonstrate that L. thermotolerans and M. pulcherrima, when used in a co-culture with S. cerevisiae, can modulate the composition of Pinot Blanc wine regarding aroma compounds, thereby positively contributing to its quality.