Production of ethanol from raw cassava starch by a nonconventional fermentation method
Article first published online: 18 FEB 2004
Copyright © 1981 John Wiley & Sons, Inc.
Biotechnology and Bioengineering
Volume 23, Issue 2, pages 291–299, February 1981
How to Cite
Ueda, S., Zenin, C. T., Monteiro, D. A. and Park, Y. K. (1981), Production of ethanol from raw cassava starch by a nonconventional fermentation method. Biotechnol. Bioeng., 23: 291–299. doi: 10.1002/bit.260230205
- Issue published online: 18 FEB 2004
- Article first published online: 18 FEB 2004
- Manuscript Accepted: 21 MAR 1980
Raw cassava root starch was transformed into ethanol in a one-step process of fermentation, in which are combined the conventional processes of liquefaction, saccharification, and fermentation to alcohol. Aspergillus awamori NRRL 3112 and Aspergillus niger were cultivated on wheat bran and used as Koji enzymes. Commercial A. niger amyloglucosidase was also used in this experiment. A raw cassava root homogenate–enzymes–yeast mixture fermented optimally at pH 3.5 and 30°C, for five days and produced ethanol. Alcohol yields from raw cassava roots were between 82.3 and 99.6%. Fungal Koji enzymes effectively decreased the viscosity of cassava root fermentation mashes during incubation. Commercial A. niger amyloglucosidase decreased the viscosity slightly. Reduction of viscosity of fermentation mashes was 40, 84, and 93% by commercial amyloglucosidase, A. awamori, and A. niger enzymes, respectively. The reduction of viscosity of fermentation mashes is probably due to the hydrolysis of pentosans by Koji enzymes.