| In the last years in Castilla la Mancha (Spain), changes are developing directed to the improvement of the wine quality and the market where they are directed. Due to the aroma is one of the sensory characteristics more valued in Enology, its involution, especially in those wines form less aromatic varieties, is one of the biotechnology challenge that research applied centres linked to this sector has raised at present.; To that, enzymatic preparations of fungal origin are used in Enology. They are a mix of glucanases with non specific activity, that may trigger collateral reactions. Therefore the study of more specific enzymatic activities (beta-glucosidases), would be the base to a new research line on applied biotechnology at the field of enzymes from wine yeasts. Their use would be a response to the current trends which go to the natural products, offering an alternative to the cocktails that are used at present.; For all that it believed opportunely to direct the present doctoral thesis to set up a rapid method to quantify the beta-glucosidasic activity in wine yeasts, to characterizing the found enzymes and to check their effect on wines of white varieties with different aromatic potential from Castilla la Mancha region.; The found results offer to the sector a protocol to search wine yeasts with beta-glucosidasic activity and a method to isolate and to quantify aroma precursors of different grape varieties. On the other hand, as results of the application of this methodology, it has been obtained a Non Saccharomyces enzymatic extract (from Debaryomyces pseudopolymorphus ) isolated from wine ecosystem that present a good behaviour on wine.; This extract can hydrolyze the precursors liberating the volatile compounds thanks to the specific reactions more controlled than the enzymatic preparations of fungal origin, for what it can replace them, getting in this way, a more genuine product that only it would be "work of yeasts". |
