Saccharomyces cerevisiae is an organism used in brewing industries for wine and beer fermentation. Brewers source it basically from foreign suppliers which make the price of beer and wine too high for local consumers. This study was aimed at isolating and identifying yeast strains from indigenous/local drinks, enriching and utilizing them in beer brewing as a substitute to the imported brewer’s yeast. The isolates, PWY from palm wine and BBY from burukutu, were enriched and tested for the characters necessary for beer brewing and compared with the commercial brewer’s yeast (CBY) which was used in top fermented beer brewing. The tested characteristics include ethanol production, sugar fermentation and flocculation ability, stress tolerance and hydrogen sulfide production during fermentation. Results showed that the isolates neither produced hydrogen sulfide gas nor ferment lactose and raffinose but were able to ferment the other sugars tested. Flocculation ability was high and they grew well in the presence of high ethanol in the fermenting mash even more than 15%(v/v). They were all viable at different degree of 96.6%, 83.0% and 91.0% for PWY, BBY and CBY respectively. The Saccharomyces spp isolated grew well between 37oC and 45oC for PWY and BBY respectively while CBY showed no growth at higher temperature of 45oC. The three isolates showed good tolerance to different stress conditions of high temperature, ethanol and sugar conditions. These local drinks can be useful if utilized for Saccharomyces cerevisiae isolation and enrichment for use in brewing industries as a substitute to the imported brewer’s yeast.
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