Biochemical changes during a submerged chickpea fermentation used as a leavening agent for bread production

Changes in enzyme activities and composition of the fermented liquid during a submerged fermentation of chickpea have been explored. Cellulase, alpha-galactosidase, invertase, amylase and proteinase activities were detected and maxima were recorded at 10, 12, 8, 10, and 16 h of fermentation, respectively. The population of bacilli in the fermentation liquid increased significantly (p < 0.05) up to 8 h and then by 0.8 log(10) cfu/mL until 12 h when it was stabilized. The clostridia also increased (p < 0.05) throughout fermentation, but most vigorously after 10 h. A gradual decrease in pH (p < 0.05) and an increase in acidity (p < 0.05) were observed from 10 h onwards. Similarly, the concentration of free fatty acids increased (p < 0.05), but appreciably after fermentation for 10 h. The amount of reducing sugars increased (p < 0.05) on fermentation for 12 h and then gradually decreased (p < 0.05). Most of the soluble carbohydrates also declined with fermentation and starch solubilization-degradation was detected after 8 h. The free amino acid content increased on fermentation, and protein degradation was evident after 8 h of incubation. Overall, the indigenous microbial population of the chickpea fermentation liquid may cause changes in its chemical constituents that can be attributed mainly to bacilli, until 8-10 h of fermentation, and to clostridia thereafter.