title: Effect of Temperature on the Prevalence ofSaccharomycesNoncerevisiaeSpecies against aS. cerevisiaeWine Strain in Wine Fermentation: Competition, Physiological Fitness, and Influence in Final Wine Composition.
abstract: Saccharomyces cerevisiaeis the main microorganism responsible for the fermentation of wine. Nevertheless, in the last years wineries are facing new challenges due to current market demands and climate change effects on the wine quality. New yeast starters formed by non-conventionalSaccharomycesspecies (such asS. uvarumorS. kudriavzevii) or their hybrids (S. cerevisiaexS. uvarumandS. cerevisiaexS. kudriavzevii) can contribute to solve some of these challenges. They exhibit good fermentative capabilities at low temperatures, producing wines with lower alcohol and higher glycerol amounts. However,S.cerevisiaecan competitively displace other yeast species from wine fermentations, therefore the use of these new starters requires an analysis of their behavior during competition withS. cerevisiaeduring wine fermentation. In the present study we analyzed the survival capacity of non-cerevisiaestrains in competition withS. cerevisiaeduring fermentation of synthetic wine must at different temperatures. First, we developed a new method, based on QPCR, to quantify the proportion of differentSaccharomycesyeasts in mixed cultures. This method was used to assess the effect of competition on the growth fitness. In addition, fermentation kinetics parameters and final wine compositions were also analyzed. We observed that some cryotolerantSaccharomycesyeasts, particularlyS. uvarum, seriously compromisedS. cerevisiaefitness during competences at lower temperatures, which explains whyS. uvarumcan replaceS. cerevisiaeduring wine fermentations in European regions with oceanic and continental climates. From an enological point of view, mixed co-cultures betweenS. cerevisiaeandS. paradoxusorS. eubayanus, deteriorated fermentation parameters and the final product composition compared to singleS. cerevisiaeinoculation. However, in co-inoculated synthetic must in whichS. kudriavzeviiorS. uvarumcoexisted withS. cerevisiae, there were fermentation performance improvements and the final wines contained less ethanol and higher amounts of glycerol. Finally, it is interesting to note that in co-inoculated fermentations, wine strains ofS. cerevisiaeandS. uvarumperformed better than non-wine strains of the same species.
authors.affiliation: Departamento de Biotecnología de los Alimentos, Grupo de Biología de Sistemas en Levaduras de Interés Biotecnológico, Instituto de Agroquímica y Tecnología de los Alimentos (IATA)-CSIC Valencia, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Alonso-Del-Real
authors.affiliation: Departamento de Biotecnología de los Alimentos, Grupo de Biología de Sistemas en Levaduras de Interés Biotecnológico, Instituto de Agroquímica y Tecnología de los Alimentos (IATA)-CSICValencia, Spain; Departament de Genètica, Universitat de ValènciaValència, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Lairón-Peris
authors.affiliation: Departamento de Biotecnología de los Alimentos, Grupo de Biología de Sistemas en Levaduras de Interés Biotecnológico, Instituto de Agroquímica y Tecnología de los Alimentos (IATA)-CSICValencia, Spain; Departament de Genètica, Universitat de ValènciaValència, Spain.
authors.forename: Eladio
authors.initials: E
authors.lastname: Barrio
authors.affiliation: Departamento de Biotecnología de los Alimentos, Grupo de Biología de Sistemas en Levaduras de Interés Biotecnológico, Instituto de Agroquímica y Tecnología de los Alimentos (IATA)-CSIC Valencia, Spain.
authors.forename: Amparo
authors.initials: A
authors.lastname: Querol
keywords: Saccharomyces species; competition; fitness; temperature; wine composition; wine fermentation