Distinctive chemical and aromatic composition of red wines produced by Saccharomyces cerevisiae co-fermentation with indigenous and commercial non-Saccharomyces strains

The use of Saccharomyces cerevisiae and non-Saccharomyces yeast species as mixed starters has advantages over pure culture fermentation because of increased wine sensory characteristics. The aim of the present study was to evaluate the divergences of wine compositions fermented by indigenous non-Saccharomyces strains (Torulaspora delbrueckii TD12 and Lachancea thermotolerans LT9) or commercial non-Saccharomyces strains (T. delbrueckii Prelude and L. thermotolerans Concerto) combined with S. cerevisiae D254, respectively. Results evidenced that although belong to the same species, the content of chemical and aromatic compounds of red wines produced by indigenous and commercial strains was significantly different after alcoholic fermentation (ALF) and malolactic fermentation (MLF). TD12/D254 was characterized with a higher amount of glycerol, ethyl esters, and volatile acids, whilst Prelude/D254 was distinguished by a higher intensity of isoamyl acetate and a lower production of acetic acid. LT9/D254 increased the intensity of higher alcohols, esters, and β-damascenone compared with Concerto/D254. After MLF, the diversities variation of glycerol and lactic acid were increased, but acetic acid and most volatile compounds were reduced. TD12/D254 obtained better aromatic quality as assessed by calculating the odor activity values (OAVs). Our results highlighted the strain-specificity of non-Saccharomyces strains in shaping the aromatic characteristic of wine, and suggested that more attention should be paid to the strain-specific characteristics when selecting non-Saccharomyces strains to improve aroma diversity and quality of the wine. In this regard, the indigenous strain is a suitable choice because of better adaptation to fermentation conditions and generating typical sensory characteristics specific to the wine region