Natural and controlled fermentation of Lima bean (Phaseolus lunatus) for daddawa production

ABSTRACT

Aims: Daddawa is a traditional fermented condiment produced from legumes in Nigeria. Lima bean is an underutilized legume in Nigeria. Natural fermentation has been the conventional method of producing daddawa but the product has been found to be of low quality and consistency. The present study aimed at comparing the microbial and biochemical changes during natural and controlled fermentation of lima bean for production of daddawa. Methodology and results: Lima bean was fermented into Daddawa naturally. It was also fermented into daddawa using pure starter culture of Bacillus subtilis and Bacillus pumilus as single starter. The microbial and biochemical changes during both fermentation conditions were evaluated. Lima bean fermented naturally (NF) recorded the highest total viable count at 48 h and 72 h of fermentation respectively. Alpha amylase and protease activities increased with fermentation, and reached their peak at 48 h in both naturally fermented lima bean and pure culture fermented lima bean samples. Lima bean fermented with B. subtilis (FBS) recorded the highest total free amino acids at 72 h (54.45 Glycine/g dry wt.). Conclusion, significance and impact of study The use of lima bean for daddawa production enhanced its utilization. Controlled fermentation of lima bean by Bacillus species improved the biochemical properties such as α-amylase and protease activities and free amino acids content of fermenting lima beans into daddawa. Keywords Daddawa; fermentation; lima bean; microbial; biochemical changes