Protective agents may minimize osmotic and thermal stresses in wine yeasts. In the present work, the tolerance of ten strains of Saccharomyces cerevisiae - two wild types and eight descendants - against three stressful agents - acetic acid, ethanol, and pH - was studied by spot dilution assay, with or without the addition of six protective vegetal extracts.
The extracts were prepared using olive pulps (cultivar Carolea), black grapes (cultivar Gaglioppo), black grape skins and black grape seeds (cultivar Magliocco canino), pomegranate albedo and pomegranate arils.
The six vegetal extracts exhibited significantly different effects on the ten yeast strains and, in general, they allow cells to overcome the stressful agents’ effects when added to the culture medium, thus, permitting to retrieve better growth rate of the yeast cells.
These results reveal interesting implications on the possibility to use protective agents in winemaking.
Article based on the poster presented at the at the 12th edition of Enoforum (Vicenza, Italy, May 21-23, 2019).