Hence, in order to address this problem, increasing the initial cell concentration together with increasing the aeration rate might be necessary. Sugar utilization further confirmed the low ethanol production and yeast cell growth. Condition (2),
where the highest ethanol production and growth were obtained, gave the lowest sugar concentration remaining at the end of fermentation: 7.05%. On the other hand, under Condition (1), with the lowest ethanol production and growth, the highest concentration of remaining sugar (10.35%) was observed. For Condition (3) and (4), the concentrations of remaining sugars were 9.24% and 7.93%, respectively