Abstract:
Sorghum is a very potential plant to be developed in Indonesia, because it has good environmental adaptation ability. Part of sorghum that used as a raw material of bio ethanol is sorghum seeds, by soaked in NaOH to remove proteins that can inhibit enzyme function. One of the use is through liquefaction and saccharification fermentation simultaneously (SFS). Liquefaction uses amylase and saccharification uses glucoamylase with yeast Pichia stipitis as fermentation agent. The purposes of this research are to determine the effect of liquefaction temperature to the sugar concentration produced and determine the best fermentation time. Liquefaction temperature was varied from 750C, 850C to 950C and fermentation time was varied from 12, 24, 48, to 72 hours at pH 5. Sample measured by alcohol meter and sugar analyzed by spectrophotometer UV-VIS. The result showed that the highest sugar concentration reached from the liquefaction by amylase is 5,211 gr/l at 850C. While the best fermentation time is 48 hours with bio ethanol concentration is 40 gr/l at 850C.
