AUTHOR=Zhang Bo-Qin , Luan Yu , Duan Chang-Qing , Yan Guo-Liang 

TITLE=Use of Torulaspora delbrueckii Co-fermentation With Two Saccharomyces cerevisiae Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile

JOURNAL=Frontiers in Microbiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2018.00606

DOI=10.3389/fmicb.2018.00606

ISSN=1664-302X

ABSTRACT=<p>The use of selected <italic>Saccharomyces</italic> and non-<italic>Saccharomyces</italic> strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous <italic>Torulaspora delbrueckii</italic> (<italic>TD</italic>12), simultaneous and sequential inoculation with two <italic>Saccharomyces</italic> strains (indigenous icewine yeast <italic>SC</italic>45 and commercial yeast BDX) with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that <italic>T. delbrueckii</italic> co-fermented with different <italic>S. cerevisiae</italic> strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA. Mixed fermentation of <italic>SC</italic>45/<italic>TD</italic>12 produced higher contents of higher alcohol (3-methyl-1-pentanol and phenylethyl alcohol), ethyl esters (ethyl decanoate and ethyl butanoate), terpenes and phenylacetaldehyde with less fatty acids (hexanoic acid, octanoic acid) and acetic acid, while BDX/<italic>TD</italic>12 generated more C<sub>6</sub> alcohol (1-hexanol) and acetate esters (ethyl acetate and isoamyl acetate). Compared to simultaneous inoculation, sequential inoculation could achieve higher aroma diversity, and generate higher intensity of fruity, flowery and sweet attributes of wine as assessed by calculating the odor activity values. The different <italic>S. cerevisiae</italic> strain and inoculation method in alcoholic fermentation could further influence the formations of aromatic compounds in malolactic fermentation. Our results highlighted the importance of <italic>S. cerevisiae</italic> strain in shaping the aromatic quality of wine in mixed fermentation, and also suggested that using different <italic>S. cerevisiae</italic> strains with distinct aromatic characteristics co-fermentation with specific non-<italic>Saccharomyces</italic> strain is a potential way to increase the aromatic diversity and quality of wine product, which could provide an alternative way to meet the requirement of wine consumers for diversified aromatic quality.</p>