Use of Indigenous Hanseniaspora vineae and Metschnikowia pulcherrima Co-fermentation With Saccharomyces cerevisiae to Improve the Aroma Diversity of Vidal Blanc Icewine

Abstract

Using novel non-<i>Saccharomyces</i> strains is regarded as an effective way to improve the aroma diversity of wines to meet the expectations of consumers. The non-<i>Saccharomyces</i> Hanseniaspora vineae and <i>Metschnikowia pulcherrima</i> have good aromatic properties useful for the production of table wine. However, no detailed information is available on their performances in icewine fermentation. In this study, simultaneous and sequential fermentation trials of indigenous <i>M. pulcherrima</i> CVE-<i>MP</i>20 or <i>H. vineae</i> CVE-<i>HV</i>11 with <i>S. cerevisiae</i> (<i>SC</i>45) were performed in 50-L fermenters of Vidal icewine, respectively. The results showed that <i>SC</i>45 cofermented with different non-<i>Saccharomyces</i> strains could generate a distinct aroma quality of icewine compared with four <i>S. cerevisiae</i> strain monocultures as evidenced by principal component analysis (PCA). Mixed fermentation of <i>MP</i>20/<i>SC</i>45 produced higher contents of acetate esters and β-damascenone with lower C₆ alcohols relative to <i>SC</i>45 monoculture. Interestingly, <i>HV11</i>/<i>SC</i>45 generated the highest amounts of C₆ alcohols [(Z)-3-hexen-1-ol and (E)-3-hexen-1-ol], higher alcohols (isobutanol, isopentanol, and 2-phenylethanol), acetate esters (2-phenethyl acetate and isoamyl acetate), <i>cis</i>-rose oxide, β-damascenone, and phenylacetaldehyde. Compared with simultaneous inoculation, sequential inoculation could achieve higher aroma diversity and produce higher intensity of fruity, flowery, and sweet attributes of icewine as assessed by calculating the odor activity values (OAVs). Our results verified the desired enological characteristics of <i>H. vineae</i> strain in icewine fermentation and also demonstrated that using indigenous non<i>-Saccharomyces</i> and <i>Saccharomyces</i> strains is a feasible way to improve aroma diversity of icewine products, which could provide an alternative way to meet the requirement of wine consumers for diversified aromatic quality.