Valorisation of potato peel wastes for bioethanol production using simultaneous saccharification and fermentation: Process optimization and kinetic assessment

Abstract

This study optimized bioethanol production from potato peel wastes on inputs of temperature, pH and solid loading using simultaneous saccharification and fermentation. Subsequently, the kinetics of yeast growth and bioethanol formation under the optimized conditions were assessed using the logistic and modified Gompertz models, respectively. Maximum bioethanol concentration (22.54 g/L) and yield (0.32 g/g) were observed under optimal process conditions of 40 °C (temperature), 5.78 (pH) and 12.25% w/v (solid loading). The logistic model gave a maximum specific growth rate and maximum cell biomass concentration of 0.20 h−1 and 2.43 g/L respectively. Furthermore, the modified Gompertz model displayed a maximum bioethanol production rate, maximum potential bioethanol concentration and a lag time of 1.51 g/L/h, 15.47 g/L and 4.66 h respectively. Optimization and kinetic findings obtained from this study provide significant knowledge for the development of simultaneous saccharification and bioethanol production processes using starch-based agricultural wastes.