Optimization of bioethanol production from durian skin by encapsulation of saccharomyces cerevisiae

The optimum condition of durian skin using SSF process with encapsulation of Saccharomyces cerevisiae takes place at pH 5.0 at 37 °C. S. cerevisiae encapsulation can increase bioethanol production activity. Bioethanol production is produced at pH 4.5; 5.0 and 5.5 were 35.85, 41.25 and 39.89 g/L medium, respectively. While using free cells S. cerevisiae, bioethanol produced was 21.42, 34.94 and 28.15 g/L medium. The percentage of bioethanol produced by S. cerevisiae was 15.3 % at pH 5.0; 40.25 % at pH 4.5 and 29.43 % at pH 5.5. Encapsulation of S. cerevisiae cells can increase the resistance to process temperature by differences in bioethanol production between encapsulation with cells free of S. cerevisiae by 19.34 % at 37 °C, 24.02 % at 40 °C and 49.01 % at 45 °C. These results are higher compared to cells free of S. cerevisiae.