Optimization of fermentation conditions for bioethanol production from cassava starch hydrolysis using central composite design approach

Current ethanol production processes utilizing crops such as sugar cane and corn starch has been well established over the decade. Other crops such as cassava, is a potential candidate in producing ethanol. Generally, very high ethanol performances in fermentation are affected by process conditions such as pH, temperature and substrate concentration. The significance of these three combined operating conditions has yet to be studied in fermentation processes. In this work, the hydrolysis of cassava starch is studied following an experimental design as a statistical problem solving approach to achieve high ethanol production. Central composite design (CCD) is used to select the most important variable from the simultaneous study on the effect of operating conditions utilized, and to optimize the process of cassava starch hydrolysis. It can be concluded that cassava starch hydrolysis is enhanced by pH, followed by substrate concentration and temperature. Model validations show good agreement between experimental results and predicted responses.