title: The grape must non-Saccharomyces microbial community: impact on volatile thiol release.
abstract: Several studies have reported the beneficial influence of non-Saccharomyces yeasts and their potential applications in the wine industry, mainly in mixed-culture fermentation with S. cerevisiae. The potential impact of 15 non-Saccharomyces strains from 7 species on 4-methyl-4-sulfanylpentan-2-one (4MSP) and 3-sulfanylhexan-1-ol (3SH) release in model medium and Sauvignon Blanc must was evaluated after partial fermentation. Whereas the impact of non-Saccharomyces on 4MSP release in both media was low, some M. pulcherrima, T. delbrueckii and K. thermotolerans strains had a high capacity to release 3SH, despite their minimal fermentation activity. As previously demonstrated for Saccharomyces yeast, this contribution is strain dependant. Taking into account their dynamic and quantitative presence during the whole process, the real impact of non-Saccharomyces yeast on 4MSP and 3SH release was evaluated using a recreated community simulating the yeast ecosystem. Our results revealed a positive impact on 3SH release in Sauvignon Blanc wines by promoting non-Saccharomyces yeast activity and delaying the growth of S. cerevisiae. Some non-Saccharomyces yeast strains are capable of making a positive contribution to volatile thiol release in wines, essentially during the pre-fermentation stage in winemaking, when this microbiological sub-population is dominant.
authors.affiliation: Université de Bordeaux-Segalen, ISVV, Bordeaux Aquitaine, USC INRA/IPB/UBS, 210 Chemin de Leysotte, CS 50008, 33882 Villenave d'Ornon Cedex, France.
authors.forename: Katharina
authors.initials: K
authors.lastname: Zott
authors.forename: Cécile
authors.initials: C
authors.lastname: Thibon
authors.forename: Marina
authors.initials: M
authors.lastname: Bely
authors.forename: Aline
authors.initials: A
authors.lastname: Lonvaud-Funel
authors.forename: Denis
authors.initials: D
authors.lastname: Dubourdieu
authors.forename: Isabelle
authors.initials: I
authors.lastname: Masneuf-Pomarede
mesh_terms: D005285:Fermentation; D000441:Hexanols / Q000378:metabolism*; D010422:Pentanones / Q000378:metabolism*; D012440:Saccharomyces / Q000254:growth & development; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D027843:Vitis / Q000382:microbiology; D014920:Wine / Q000382:microbiology*; D015003:Yeasts / Q000254:growth & development*
chemical_list: D000441:Hexanols; D010422:Pentanones; D013438:Sulfhydryl Compounds; C530764:4-methyl-4-sulfanylpentan-2-one; C477019:3-mercaptohexanol