Microorganisms associated with natural fermentation of African yam bean (Sphenostylis sternocarpa Harms) seeds for the production of otiru

Abstract

In this study African yam bean Seed (cream colour variety) were fermented naturally at 30±2°C for 72, 96 and 120 h, respectively. The bacteria isolated during the process include Lactobacillus jensenii, Bacillus coagulans, Aerococcus viridans and Pediococcus cerevisiae while the yeast were Saccharomyces cerevisiae and Candida mycoderm. Aspergillus niger was the only mould isolated from raw seed which disappeared after dehulling. The microbial loads increased with period of fermentation up to 72 h but decreased at 96 and 120 h of fermentation. Before fermentation, the bacterial count was 6.0×102 cfu g-1 While at 24, 48 and 72 h the bacterial load increased to 7.0×103, 7.8×103 and 8.5×103 cfu g-1, respectively. The highest bacterial load was observed after 72 h of fermentation. The load decreased to 4.3×103 and 2.1×103 cfu g-1 at 96 and 120 h of fermentation. In addition the yeast cells load increased up to 72 h of fermentation and the load decreased at 96 and 120 h, respectively. © 2007 Academic Journals Inc.