Yeast stress responses to acclimation for sparkling wine production

Identificador:  TDX:2383

Handle: https://hdl.handle.net/20.500.11797/TDX2383

Autors:  Borrull Riera, Anna

Resum:
he present doctoral thesis deepends knowledge of the stress responses of yeast during acclimation process to perform secondary fermentation for sparkling wine production. The main stress factor, ethanol has as synergic effect with many others. Even acclimation process of yeast cells before being inoculated into secondary fermentation have been done by winemakers for ages, the lag phase after inoculation and the short cell proliferation indicate cells yeast are not completely adapted. Such a complex scenario should be studied to avoid cells susceptible to death which would stop fermentation before finishing. A cytological, metabolomic and lipidomic study has been done of acclimated cells; pointing out the conditions (as sugar and oxygen availability) to get the best cellular diagnostic as possible and the key factors (as vacuolar activity and morphology, carbohydrate reserves, reactive oxygen spices accumulation or membrane rigidity) which could confirm yeasts are ready to perform secondary fermentation.