Identificação das leveduras isoladas de uvas cultivadas no Vale do Submédio São Francisco e sua utilização na fermentação do mosto de uva

Abstract

The vineyards cultivation and wine manufacture in the São Francisco Submid Valley region is an activity that has been expanding and gaining ground on the domestic and international markets. For preparation of wine in this region selected yeasts are used and imported S. cerevisae species and S. cerevisae species, bayanus variety, this trend may be taking off the typical characteristics of the wines produced in the region. This study aimed to isolate and identify grapes yeasts Vitis viníferas L., cultivated in the São Francisco Submid Valley region and select those that present potential for the fermentative production of wine. Yeasts were isolated and identified using biochemical and molecular evidence. Were isolated 60 indigenous yeasts found in the YM/Agar medium and all belonging to the Group of non-Saccharomyces. According to the physiological/biochemical tests of 60 isolated 20 colonies could not be grouped into no gender. However 40 of these were suggestive of belong to the Hanseniaspora spp gender. From these 17 were identified until the species, being suggestive of Hanseniaspora guilliermondi (anamorph Kloeckera apis). The two non-Saccharomyces strains used in the fermentative trials were identified through the sequencing D1/D2 region of 26S subunit of the ribosomal RNA in Hanseniaspora opuntiae and Cryptococcus flavescens. These lineages identified by molecular biology along with Saccharomyces cerevisae species commercially acquired were used to achieve fermentation in laboratory scale in Chenin blanc, Rosé and Cabernet sauvignon grape must to study the kinetics of fermentation through the determination of cell biomass and pH for seven days. H. opuntiae was nonSaccharomyces yeast whose value cell biomass does not detract from the end of the 168 hours of fermentation. The pH of fermented musts remained on track ideal for production of White, Rosé and Red wine. Affective sensory tests were conducted to determine the aromatic profile of fermented musts by yeasts nonSaccharomyces, H. opuntiae and C. Flavescens and S. cerevisae species. The acceptability of samples and purchase intention of musts in relation to flavourings in White, Rosé and Red wines was evaluated in periods of 72; 96 and 120 hours of fermentation. The variance univariate analysis (ANOVA) held between samples, indicated that the aroma produced by fermented must Chenin blanc by yeast H. opuntiae, presented the highest average acceptance (7.3) within 120 hours, with intent to purchase of 76. The aroma produced by yeasts H. opuntiae and S. cerevisae species in Rosé must presented the highest average acceptance during periods of 72 and 96 hours (7.16 and 7.12) the day of sensory analysis, the xv highest average purchase intention was in period of 96 hours (74%). The highest average acceptance aroma produced by H. opuntiae and S. cerevisae species in fermentation of Cabernet sauvignon must was to periods of 72 and 96 hours (5.26 and 5.66). The maximum percentage of purchase intention of this must was 32. The non-Saccharomyces yeasts particularly apiculates, can contribute to the formation of pleasant aroma. Keywords: non-Saccharomyces, biomass, affective sensory tests.