Bioethanol Production from Rice Winery Cake Using Lactic Acid Bacteria and Yeasts by the Process of Simultaneous Saccharification and Fermentation

摘要

Bioethanol is a sustainable energy source which serves as an alternative to fossil fuel and contributes to a clean environment. Bioethanol was produced by individual activities of lactic acid bacteria and yeasts from rice cake waste using a simultaneous saccharification and fermentation process. The rice cake waste is a filtered solid waste of fermented rice wine mash and contains 78.04% of total carbohydrate, 10.88% of protein, 2.26% of ash, 8.12% of moisture and 0.7% of fat. The rice cake was mixed with raw starch digesting enzyme of Aspergillus niger and (Lactobacillus fermentum, Rhodotorula minuta, Rhodotorula mucilagnosa, Candida krusei, Kodamara ohmeri) respectively into different fermenting chambers. Rhodotorula minuta produced the highest efficiency of ethanol of 52.06% at the temperature of 30℃ and pH of 2.58. Reducing sugar was observed to decrease with increase in bioethanol production and cell growth increased as the fermentation time increases. Bioethanol can also be produced from rice cake waste of a fermented rice mash, which can serve as a bio fuel and contributes to a healthy environment.