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 char acterization to be used during,industrial fermentation processes, allowing the detection of yeast contaminants. Five strains of yeast currently used i n the Brazilian fuel alcohol industry (about 99% of the yeast used for this purpose), and yeast strains isolated from the five major beer industries t hat represent 95% of the Brazilian beer market were evaluated for their gro wth and absorption of dyes on differential culture media, their total prote in electrophoretic patterns (SDS-PAGE), CHEF chromosome separation patterns and RAPD profiles. For the identification of brewing yeast all rested meth ods were efficient, allowing the identification of at least two different s pecies, one of which was Saccharomyces cerevisiae. The strains used for the fuel alcohol industries were best characterized by SDS-PAGE and RAPD analy sis. Those strains share high level of genetic similarity and they are ail known as S. cerevisiae strains. (C) 2000 Academic Press.