RT info:eu-repo/semantics/doctoralThesis
T1 Estudio de la biodiversidad de levaduras procedentes de uva verdejo de la D.O. Rueda
A1 López Enríquez, Lorena
A2 Universidad de Valladolid. Escuela de Doctorado
K1 Levadura
K1 Yeast diversity
K1 Diversidad de levaduras
K1 Strain biotyping
K1 Biotipificación de cepas
K1 Wine yeast
K1 Levadura vínica
K1 2414.10 Micología (Levaduras)
AB The diversity of wine yeast species is directly influenced by climate, annual weather conditions, topography of vineyard plots, genetic diversity of vineyards, viticultural management system, and oenological practices. Understanding the interaction between these factors and the microbiota associated with the winemaking process and their contribution for the production of differentiated and quality wines is currently a challenge of interest.This work began with the molecular study of 484 isolates of native wine yeasts obtained from the spontaneous fermentation of grapes of the Verdejo variety, considering three different vineyards, two vintages and five stages of the winemaking process. Molecular characterisation determined the composition of the yeast communities related to each fermentation stage, demonstrating a high inter- and intraspecies genetic variability. In addition, this classification allowed the study of the biodiversity of the yeast populations associated with each vineyard and each vintage, showing a decrease in diversity as the fermentation progresses, a common population structure marked by the dominance and ubiquity of some genetic groups, and yeast populations characteristic of each vineyard and vintage.The technological application of the study of native yeast populations requires the evaluation of the oenological traits of the different genetic groups. For this purpose, both their fermentative behaviour and their enzymatic profile in relation to the production of oenologically relevant enzymatic activities were considered. These results proved an important intra-species technological variability and underlined the oenological potential of some Saccharomyces cerevisiae and Wickerhamomyces anomalus isolates.Native strains were selected based on previous identification, characterisation, and technological behaviour, and mixed fermentation trials were proposed by sequential inoculation of non-Saccharomyces and S. cerevisiae yeasts, using Verdejo grapes. The development of the mixed fermentations revealed an optimal kinetic evolution and an adequate implantation of the yeast strains used as starter cultures. The analysis of the volatile organic compounds in the wines showed a singular aromatic profile, highlighting the influence of the native microbiota on the characteristics of the final product and its importance in the quality, typicity and uniqueness of these wines.
YR 2024
FD 2024
LK https://uvadoc.uva.es/handle/10324/69450
UL https://uvadoc.uva.es/handle/10324/69450
LA spa
NO Escuela de Doctorado
DS UVaDOC
RD 01-sep-2024