OPTIMIZATION OF SACCHAROMYCES CEREVISIAE FERMENTATION OF MAIZE BRAN TO ETHANOL

Abstract

This study explores the optimization of bioethanol production from maize bran through hydrolysis and fermentation processes. Maize bran and sweet potatoes were procured as primary materials, and Saccharomyces cerevisiae was employed for fermentation. The maize bran was processed to a powdered form and hydrolyzed using crude β-amylase enzyme extracted from sweet potatoes. The hydrolysis was optimized using the Taguchi method, examining factors such as temperature (30°C, 40°C, 50°C), substrate concentration (2%, 6%, 10%), and duration (1, 3, 6 hours). Glucose content was analyzed using the DNS method. Subsequently, the fermentation process was also optimized with varying yeast loading rates (1%, 10%, 20%), temperatures (30°C, 40°C, 50°C), and durations (1, 3, 6 hours). Ethanol yield was determined using a distillation apparatus and alcohol meter. The results demonstrated that the highest glucose yield (95 mg) was achieved at 6% substrate concentration hydrolyzed at 50°C for 6 hours. Optimal ethanol production (1.60%) occurred at 30°C with a 10% yeast loading rate, fermenting for 6 hours. These findings suggest that precise control of substrate concentration, temperature, and process duration are critical for maximizing biogas yield from maize bran. Further research is recommended to refine these parameters and explore extended hydrolysis and fermentation periods.