The potential of sweet potato biorefinery and development of alternative uses

The bioethanol production from the sweet potato variety BRS Cuia using three different strains of Saccharomyces cerevisiae (LPB1-93, ATCC-26602, and CA-11) was carried out in this research. Comparative analyses of consumed sugar, ethanol yield, and productivity (in tons per hectare) increased along with the concentration of cells in the inoculum. Additionally, to verify the aromatic quality of a potential sweet potato distilled spirit, volatile organic compounds were analyzed. The results showed a yield of over 90% ethanol. It was observed that the sugar consumption and ethanol production rates can be increased with a higher initial concentration of cells. This resulted in higher concentrations of ethanol in shorter times. From 100 g of the sweet potato variety BRS Cuia, the highest concentration of ethanol obtained was 25.74 g L^-1 using the LPB1-93 strain. The estimated bioethanol production is about 10,000 L ha^-1, with two sweet potatoes crops in a year. The ethanol production from the sweet potato variety BRS Cuia is viable, representing a sustainable alternative to fuel bioethanol, as well as an alcoholic beverage due to the volatile organic compounds present in the distilled fraction.