Methods for yeast characterization from industrial products

This work compared the efficiency of four methods for the identification of industrial yeast strains and the establishment of a pattern for yeast characterization to be used during,industrial fermentation processes, allowing the detection of yeast contaminants. Five strains of yeast currently used in the Brazilian fuel alcohol industry (about 99% of the yeast used for this purpose), and yeast strains isolated from the five major beer industries that represent 95% of the Brazilian beer market were evaluated for their growth and absorption of dyes on differential culture media, their total protein electrophoretic patterns (SDS-PAGE), CHEF chromosome separation patterns and RAPD profiles. For the identification of brewing yeast all rested methods were efficient, allowing the identification of at least two different species, one of which was Saccharomyces cerevisiae. The strains used for the fuel alcohol industries were best characterized by SDS-PAGE and RAPD analysis. Those strains share high level of genetic similarity and they are ail known as S. cerevisiae strains. (C) 2000 Academic Press.