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In order to phenotypically characterized Saccharomyces cerevisiae strains isolated from sorghum beer and palm wines for a possible selection of a starter culture, 30 strains were tested for killer activity, temperature resistance, ethanol tolerance, carbohydrate fermentation, enzyme profile and sorghum wort fermentation. Of the tested strains, three showed a killer profile, while four showed a neutral profile and 23 were found to be sensitive to K2 toxin. Temperatures of 40 °C and 44 °C allowed to distinguish strains into four thermal groups with only three strains may grow at 44 °C. Almost tested strains were tolerant to 5% ethanol with viability rates up to 73%. But at 10% and 15% ethanol, respectively 18 and 7 strains were tolerant. Carbohydrate fermentation revealed 13 fermentation profiles, including one typical and 12 atypical profiles. The typical profile strains (16.13% of the strains) fermented glucose, galactose, fructose, sucrose, maltose, trehalose and raffinose. Most of the strains secreted lipases (mainly esterase and esterase-lipase), proteases (mainly valine and cysteine arylamidase, chrymotrypsin) and phosphatases (mainly acid phosphatase and naphthol phosphohydrolase). On contrary, only five strains isolated from sorghum beer exhibited glucosidase activity, mainly α-glucosidase. The analyse of fermented sorghum wort revealed that fermentative performance is strain dependent. Furthermore, the Hierarchical Cluster Analysis showed that the strains were separated in three distinct clusters with the strains from sorghum beer clustered separately.

Starter cultures of Candida tropicalis and Saccharomyces cerevisiae isolated from tchapalo were tested in pure culture and co-culture of four ratios [2:1, 25:4, 1:4, 2:3 (cells/cells)] for their ability to ferment sorghum wort to produce tchapalo. All the starters showed means growth rate between 0.043 and 0.101 h−1. Only C. tropicalis in pure culture showed growth rate lower than that of S. cerevisiae in single culture. During fermentation, according to total soluble solids depletion, yeast starters could be grouped in four different profiles. But in the beer produced, total soluble solids contents were statistically identical. The lowest values were obtained with co-culture C. tropicalis + S. cerevisiae in the ratios of 2:1 and 2:3. Starter cultures with large ratio of C. tropicalis produced a higher organic acids and 2-butanone than S. cerevisiae in pure culture. However, co-culture C. tropicalis + S. cerevisiae (2:1) was the alone starter which produced higher ethanol than S. cerevisiae in pure culture. The beers produced with C. tropicalis + S. cerevisiae (25:4), C. tropicalis + S. cerevisiae (1:4) and C. tropicalis were widely different from those produced with the others starter cultures.