Search results for "Wine fermentation"

Differential Contribution of the Parental Genomes to a S. cerevisiae × S. uvarum Hybrid, Inferred by Phenomic, Genomic, and Transcriptomic Analyses, …

2020

In European regions of cold climate, S. uvarum can replace S. cerevisiae in wine fermentations performed at low temperatures. S. uvarum is a cryotolerant yeast that produces more glycerol, less acetic acid and exhibits a better aroma profile. However, this species exhibits a poor ethanol tolerance compared with S. cerevisiae. In the present study, we obtained by rare mating (non-GMO strategy), and a subsequent sporulation, an interspecific S. cerevisiae × S. uvarum spore-derivative hybrid that improves or maintains a combination of parental traits of interest for the wine industry, such as good fermentation performance, increased ethanol tolerance, and high glycerol and aroma productions. G…

Effect of temperature on the prevalence of Saccharomyces non-cerevisiae species against a S. cerevisiae wine strain in wine fermentation: competition…

2017

Saccharomyces cerevisiae is 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-conventional Saccharomyces species (such as S. uvarum or S. kudriavzevii) or their hybrids (S. cerevisiae x S. uvarum and S. cerevisiae x S. 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. cerevisiae can competitively displace other yeast species from wine fermentations,…

The Use of Mixed Populations of Saccharomyces cerevisiae and S. kudriavzevii to Reduce Ethanol Content in Wine: Limited Aeration, Inoculum Proportion…

2017

Saccharomyces cerevisiae is the most widespread microorganism responsible for wine alcoholic fermentation. Nevertheless, the wine industry is currently facing new challenges, some of them associate with climate change, which have a negative effect on ethanol content and wine quality. Numerous and varied strategies have been carried out to overcome these concerns. From a biotechnological point of view, the use of alternative non-Saccharomyces yeasts, yielding lower ethanol concentrations and sometimes giving rise to new and interesting aroma, is one of the trendiest approaches. However, S. cerevisiae usually outcompetes other Saccharomyces species due to its better adaptation to the fermenta…

Inoculation of Torulaspora delbrueckii as a bio-protection agent in winemaking

2018

International audience; In oenology, bio-protection consists in adding bacteria, yeasts or a mixture of microorganisms on grape must before fermentation in order to reduce the use of chemical compounds such as sulphites. More particularly, non-Saccharvinyces yeasts are used as a total or partial alternative to sulphites. However, scientific data capable of proving the effectiveness of adding these yeasts on grape must is lacking. This study reports the analysis of antimicrobial and antioxidant effects of one non-Saccharamyces yeast, Torulaspora delbruecicii, inoculated at the beginning of the white winemaldng process in two Burgundian wineries as an alternative to sulphiting. The implantati…

Beneficial effects of Candida zemplinina in wine fermentation: lower alcohol level and higher glycerol content

2012

Effects of temperature, pH and sugar concentration on the growth parameters of Saccharomyces cerevisiae, S. kudriavzevii and their interspecific hybr…

2008

The effects of temperature, pH and sugar concentration (50% glucose + 50% fructose) on the growth parameters of Saccharomyces cerevisiae T73, S. kudriavzevii IFO 1802T and the hybrid strain S. cerevisiae × S. kudriavzevii W27 were studied by means of response surface methodology based in a central composite circumscribed design. Lag phase could not be properly modelled in the wine model system, where yeasts started the fermentation in few hours after inoculation. In the case of the maximum specific growth rate (μ max), the temperature was the most important variable for three yeasts, although the effects of sugar concentration (in T73 and W27) and pH (W27 and 1802) were also significan…

Indigenous yeast communities in the environment of ‘‘Rovello bianco’’ grape variety and their use in commercial white wine fermentation

2009

The indigenous yeast communities associated with several vineyard habitats were analysed. Wild yeasts were isolated, differentiated at strain level and identified. A phylogenetic tree based on partial 26S rRNA genes was constructed. The strains were characterized and the indigenous Saccharomyces cerevisiae GR1 was then used to carry out a vinification process and compared with a commercial yeast. Wines obtained were subjected to chemical and sensory analysis. The comparison between the two products highlighted differences due to the fer- menting strains employed. The vineyard environment was found to strongly influence the composition of yeast communities, thus, confirming the theory of ‘te…

Yeast ecology of vineyards within Marsala wine area (western Sicily) in two consecutive vintages and selection of autochthonous Saccharomyces cerevis…

2012

In this work, the yeast ecology associated with the spontaneous fermentation of Grillo cultivar grapes from 10 vineyards was analyzed from grape harvest till complete consumption of must sugars. The microbiological investigation started with the plate count onto two culture media to distinguish total yeasts (TY) and presumptive Saccharomyces (PS). Yeasts were randomly isolated and identified by a combined genotypic approach consisting of restriction fragment length polymorphism (RFLP) of 5.8S rRNA gene and 26S rRNA and sequencing of D1/D2 domain of the 26S rRNA gene, which resulted in the recognition of 14 species belonging to 10 genera. The distribution of the yeasts within the vineyards s…

Mitotic Recombination and Genetic Changes in Saccharomyces cerevisiae during Wine Fermentation

2000

Natural strains of Saccharomyces cerevisiae are prototrophic homothallic yeasts that sporulate poorly, are often heterozygous, and may be aneuploid. This genomic constitution may confer selective advantages in some environments. Different mechanisms of recombination, such as meiosis or mitotic rearrangement of chromosomes, have been proposed for wine strains. We studied the stability of the URA3 locus of a URA3/ura3 wine yeast in consecutive grape must fermentations. ura3/ura3 homozygotes were detected at a rate of 1 x 10(-5) to 3 x 10(-5) per generation, and mitotic rearrangements for chromosomes VIII and XII appeared after 30 mitotic divisions. We used the karyotype as a meiotic marker an…

The Use of Mixed Populations of

2017

Saccharomyces cerevisiae is the most widespread microorganism responsible for wine alcoholic fermentation. Nevertheless, the wine industry is currently facing new challenges, some of them associate with climate change, which have a negative effect on ethanol content and wine quality. Numerous and varied strategies have been carried out to overcome these concerns. From a biotechnological point of view, the use of alternative non-Saccharomyces yeasts, yielding lower ethanol concentrations and sometimes giving rise to new and interesting aroma, is one of the trendiest approaches. However, S. cerevisiae usually outcompetes other Saccharomyces species due to its better adaptation to the fermenta…