Simultaneous saccharification and juice co-fermentation for high-titer ethanol production using sweet sorghum stalk

The acid pretreated sweet sorghum bagasse was mixed with the fermentable juice for ethanol production by simultaneous saccharification and juice co-fermentation (SSJcF). The effect of sulfuric acid concentration on ethanol production was evaluated. Two-phase of fermentation was occurred distinctly during the process. Under the optimized conditions (2% of sulfuric acid and 20 FPU/g of cellulase added at 0 h), 120.41 ± 0.4 g/L of ethanol was achieved after 216 h of inoculation, with ethanol yield of 67.75 g/kg of the fresh sweet sorghum stalk (FSSS) that contained water and was rich in monosaccharide and cellulosic biomass. This study provided a potential way for high titer ethanol production by SSJcF using FFFS, which is benefited to the downstream ethanol separation processes.