Journal of Microbial & Biochemical Technology

Abstract

Extrusion with Thermostable α-amylase Injection as Pretreatment Method for Ethanol Production from Corn Starch

Lin Myat and Gi-Hyung Ryu

Pretreatment technologies have been developed to increase the bioconversion rate of biomass into fermentable sugar. The objective of this research was to investigate extrusion with thermostable α-amylase injection at different melt temperatures 95, 115 and 135°C on functional properties, ethanol content and conversion (%) of corn starch extrudates. Saccharomyces cerevisae (ATCC 24858) was used for ethanol production. In the present study, significant increase in ethanol production was achieved by the injection of thermostable α-amylase during extrusion process at melt temperature 115°C. The data clearly showed that thermostable α-amylase injection gave significantly increased (p<0.05) ethanol content at melt temperature 115°C from fermentation period from 24 to 48 hr. Industrial bio-ethanol production by direct fermentation following extrusion with thermostable α-amylase injection and omitting the saccharification step will be very effective in reducing ethanol production costs in countries like U.S. Therefore, ethanol production from extruded corn starch with thermostable α-amylase injection is a significant finding that could be applied to improve bioconversion rate for ethanol production.