Scientific African (Jul 2020)
A study on effect of fermentation conditions on citric acid production from cassava peels
Abstract
In this study, effect of fermentation conditions (solid state fermentation and submerged fermentation) on the yield of citric acid from cassava peels was evaluated. Cassava peels were hydrolysed to get reducing sugar using Hydrochloric acid and then inoculated with Aspergillus niger for citric acid production. The parameters of experiments were inoculum concentration (7–11%), fermentation time (1–4 days), temperature (23–39 °C) and ethanol concentration (0–4%). The lowest and highest values of citric acid recorded in solid state fermentation were 2.6 and 4.9 g/l respectfully, while the lowest and highest values for citric acid in submerged fermentation were 0.68 and 1.68 g/l respectfully. Also the results of lowest and highest values of sugar acid ratio observed in solid state fermentation were 6 and 16.04 while the lowest and highest values for sugar acid ratio in submerged fermentation were 1.5 and 7.2 respectively. Only the inoculum concentrations and time played dominant roles in the production of citric acid while all the parameters played active role in the production of sugar-acid-ratio from cassava peels.