"Wild Yeast
Many Rías Baixas winemakers now favour fermenting their grapes with the native yeasts found in their vineyards. Though it can be challenging to make wine with wild yeasts, they believe the resulting aromas are a more authentic reflection of the characteristics of the Albariño grape and their terroir."
http://www.telegraph.co.uk/food-and-drink/wine/wild-yeast-fermenting-risky-radical-but-the-route-to-better-wine/
https://www.theglobeandmail.com/life/food-and-wine/wine/what-is-wild-yeast-the-ingredient-thats-all-the-rage-in-wine-beer-and-cider/article34148939/
And eventually:
Csoma, H., et al., 2010, “Biological diversity of Saccharomyces yeasts of spontaneously fermenting wines in four wine regions: Comparative genotypic and phenotypic analysis”, IntJ FoodMicrobiol140, 239–248.
McGuireD., etal., 2011, “Selection and characterization of autochthonous yeast starter strains isolated from Portuguese musts”, 9e SymposiumInternationalD'OenologieDe Bordeaux.
Pretorius, I. S., 2000, “Tailoringwineyeastfor the new millennium: novel approaches to the ancient art of wine-making”, Yeast16, 675-729.
Rodriguez-Palero, et al., 2013, “SelectionofanautochthonousSaccharomycesstrainstarterfor alcoholicfermentationofSherrybase wines”, J IndMicrobiolBiotechnol40, 613–623.
Tosi, E., etal., 2009, “Evidence of different fermentation behaviours of two indigenous strains of Saccharomyces cerevisiae and Saccharomyces uvarum isolated from Amarone wine”, J ApplMicrobiol107, 210–218.
Tristezza, M., etal., 2012, “Autochthonous fermentation starters for the industrial production of Negroamaro wines”, J IndMicrobiolBiotechnol39, 81–92.
Csoma
Abstract Article history: Received 4 July 2009 Received in revised form 16 February 2010 Accepted 13 March 2010 Keywords: Wine Yeasts Biodiversity Fermentation Secondary metabolites Combination of molecular genetic analysis (karyotyping, PCR-RFLP of MET2, the ITS1-ITS2 region and the NTS region) and physiological examination (melibiose and mannitol utilization, sugar-, ethanol- and copper tolerance, killer activity, fermentation vigor and production of metabolites) of yeasts isolated from spontaneously fermenting wines in four wine regions revealed very high diversity in the Saccharomyces cerevisiae populations. Practically each S. cerevisiae isolate showed a unique pattern of properties. Although the strains originating from the same wine were quite similar in certain traits, they showed diversity in other properties. These results indicate that alcoholic fermentation in grape wines is performed by highly diverse yeast consortia rather than by one or two dominating strains. The less frequent Saccharomyces uvarum strains were less diverse, showed lower karyotype variability, were Mel+, Man+, more sensitive to 60% sugar, and ethanol or copper in the medium. They produced less acetic acid and fermented better at 14 °C than most of the S. cerevisiae isolates, but certain S. cerevisiae strains showed comparably high fermentation rates at this temperature, indicating that it is not a general rule that S. uvarum ferments better than S. cerevisiae at low temperatures. The segregation of certain traits (melibiose utilization, mannitol utilization and copper resistance) in both species indicates that the genomes can easily change during vegetative propagation. The higher diversity among the S. cerevisiae isolates suggests that the S. cerevisiae genome may be more flexible than the S. uvarum genome and may allow more efficient adaptation to the continuously changing environment in the fermenting wine.
Csoma
Abstract Article history: Received 4 July 2009 Received in revised form 16 February 2010 Accepted 13 March 2010 Keywords: Wine Yeasts Biodiversity Fermentation Secondary metabolites Combination of molecular genetic analysis (karyotyping, PCR-RFLP of MET2, the ITS1-ITS2 region and the NTS region) and physiological examination (melibiose and mannitol utilization, sugar-, ethanol- and copper tolerance, killer activity, fermentation vigor and production of metabolites) of yeasts isolated from spontaneously fermenting wines in four wine regions revealed very high diversity in the Saccharomyces cerevisiae populations. Practically each S. cerevisiae isolate showed a unique pattern of properties. Although the strains originating from the same wine were quite similar in certain traits, they showed diversity in other properties. These results indicate that alcoholic fermentation in grape wines is performed by highly diverse yeast consortia rather than by one or two dominating strains. The less frequent Saccharomyces uvarum strains were less diverse, showed lower karyotype variability, were Mel+, Man+, more sensitive to 60% sugar, and ethanol or copper in the medium. They produced less acetic acid and fermented better at 14 °C than most of the S. cerevisiae isolates, but certain S. cerevisiae strains showed comparably high fermentation rates at this temperature, indicating that it is not a general rule that S. uvarum ferments better than S. cerevisiae at low temperatures. The segregation of certain traits (melibiose utilization, mannitol utilization and copper resistance) in both species indicates that the genomes can easily change during vegetative propagation. The higher diversity among the S. cerevisiae isolates suggests that the S. cerevisiae genome may be more flexible than the S. uvarum genome and may allow more efficient adaptation to the continuously changing environment in the fermenting wine.
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