Bioethanol from valencia orange (Citrus sinensis) through fermentation

The aim of this study is to produce bioethanol from orange peels using fermentation process and the parameter of temperature, pH and fermentation time were studied at the same time. Saccharomyces cerevisisae was used in the experiment for fermentation purpose. The temperature (30, 35 and 40 °C), pH (5, 7 and 9) and fermentation time (24, 48 and 72 hours) were varied to determine their effects on ethanol yield. The fermentation was done under constant temperature of 30 °C and pH of 5. The fermentation process was carried out for 48 hours or 2 days. The ethanol concentration in sample were determined by testing the samples using High Performance Liquid Chromatography (HPLC). The highest bioethanol concentrations were obtained at temperature of 35 °C, pH 5 and fermentation time of 72 hours. This indicated that at pH 5, temperature 35 °C and fermentation time of 72 hours were the optimum conditions for the yeast to produce bioethanol.