Isolation of new types of yeasts strains from indigenous flora of Iaşi vineyards

Abstract

The alcoholic fermentation of grapes must is highly desired when the yeasts are tolerant to high osmotic pressure due to high concentrated sugar and resistant to the toxic effects of the high alcohol concentration. In this context, the research led to the selections made from Iasi vineyard – Copou vine centre of new yeast strains with strong alcooligen character, Sacchoramyces genus. New strains of isolated and selected yeasts have the ability to achieve full alcoholic fermentation and has a good tolerance to high alcohol concentrations (15.0 to 16.0 vol % alcohol). They may also restart the alcoholic fermentation when the process was stopped at a concentration of 8.5 to 11.5% alcohol by volume and still have a residual sugar content of 60 - 100 g/L.