CHARACTERISTIC AND AMYLASE ACTIVITY OF YEASTS ISOLATED FROM Banh men la STARTER TABLETS IN CENTRAL VIETNAM

Banh men la is a traditional starter tablet for rice-based traditional alcoholic beverages in high-land regions of Vietnam, from minority ethnic groups. The main materials be used for Banh me la starter are starch, leaves and other parts of medicinal plants, or sometimes enrich microflora community by adding yeast, fungi, and other microorganisms. The aim of this study was to isolate the high amylase-producing yeast strains with crucial contribution to alcohol production from Banh me la starter granules. Nineteen yeast strains were successfully isolated from banh men la wine starter tablets collected in Quang Tri and Quang Ngai. Four Saccharomyces yeasts, A3(1), A3(2), 1(2) and 5(2), produced high alcohol and amylase activity levels. The optimum alcohol production and amylase activity were obtained when the yeasts were cultured on a sucrose medium at 35°C and shaken at a speed of 180 rpm. The molecular weight of amylases was determined at approximately of 43 kDa. Yeast A3(1) was the best alcohol and amylase producing strain with an alcoholic content of 45.33 g/100 mL and an amylase activity of 104.46 u/mL. The four Saccharomyces strains, A3(1), A3(2), 1(2) and 5(2) showed potential for the use in the production of high quality starter tablets for traditional rice-based wine production.