A rapid method for testing yeast resistance to ethanol for the selection of strains suitable for winemaking

摘要

The paper presents a rapid and convenient method for assessing the yeast tolerance to ethanol. An isothermal calorimeter with 24 sample cells for microbial cultures was used to monitor the growth of yeast cultures on glucose-peptone broth at 30°C, in the presence of various concentrations of ethanol added from the beginning. The apparatus detects the heat evolved during the yeast growth and records it under the form of the so-called “growth thermograms”. These curves are then analyzed using a specialized mathematical apparatus to derive values of various parameters which describe the effect of the ethanol on the yeast growth, such as the concentration which inhibits 50% of the microbial growth (LD50) or the minimum inhibitory concentration (MIC).