Thermo-enzymatic hydrolysis of Cassava Starch by α-amylase and amyloglucosidase

Abstract

One of the greatest challenges for the 21st century society is to meet the growing demand for energy for transportation in sustainable way. Petroleum based products are in critical state and alternatives for fuel is needed. One of the alternatives is ethanol, which adds octane value to gasoline blend and provides a cleaner burning. This paper discusses the thermo-enzymatic hydrolysis of Manihot esculenta (cassava) starch in order to produce sufficient glucose for ethanol production. The favorable starch concentration for the hydrolysis was found to be 30% with the addition of 0.25% α-amylase for liquefaction and 0.15% amyloglucosidase for saccharification. This combination resulted in producing 204.5 g/l glucose. For fermentation condition, a 30% slurry resulted better glucose comsumption by Saccharomyces cerevisiae than the 20% slurry. However, the 10% inoculum was considered inadequate for the conversion of glucose to ethanol.