Possibilities of improving the bioethanol production from cornmeal by yeast saccharomyces cerevisiae var. ellipsoideus

Abstract

Bioethanol has become one of the most promising biofuels today. In Serbia, the most suitable and available raw materials are conventional starch-based energy crops such as corn and triticale. Bioethanol production by simultaneous saccharification and fermentation (SSF) process of cornmeal using free and immobilized cells of Saccharomyces cerevisiae var. ellipsoideus yeast, with and without media supplementation (mineral salts ZnSO4·7H2O and MgSO4·7H2O), in a batch system is studied. The ethanol concentration after 48 h of SSF is increased for 6.68 % by yeast immobilization compared to the free cell system, and a percentage of the theoretical ethanol yield of 86.66 % is achieved. Further improvement is accomplished with the addition of mineral salts which contributed to the highest increase in ethanol concentration by 15.86 % compared to the SSF process with free yeast and without yeast activators. In this case, ethanol concentration of 10.23 % (w/w), percentage of the theoretical ethanol yield of 94.11 %, and glucose consumption of 98.32 % are achieved after 48 h of the SSF process.on, and the impact of the developed hydrogen production models on global warming is set forth.