Etudaiye H. Adinoyi, Oti E., Sanchez T., Omodamiro R. Majekodunmi, Afuape O. Solomon and Ikpeama A.
Flours and starches were processed from three sweetpotato varieties namely TIS 2352.OP.113, TIS 8164 and TIS 87/0087. The flours and starches were fermented employing the granular starch hydrolyzing enzyme, stargen 00l and the yeast Saccharomyces cereviciae. The flours and starches were analysed for moisture/dry matter, fibre, amylose and amylopectin contents whereas their slurries were analysed for glucose contents, pH, total titratable acidity (TTA) and temperature during the 72hrs of fermentation. The ethanol yield of the flours and starches were determined. Significant differences (P<0.05) were found among the sweetpotato flours and starches with respect to moisture/dry matter, fibre, amylose and amylopectin contents. The ethanol yield of the flours and starches tended to be dependent on their amylose contents. The average yield of ethanol (19.94%) of the sweetpotato starches was higher than the average ethanol yield (15.19%) of the flours. The glucose contents and the pH of the fermenting slurries of the flours and starches decreased as fermentation progressed, whereas their TTA and temperatures generally increased. The sweet potato variety TIS 2352.OP.113 is recommended for exploitation for ethanol production and as a source of renewable energy.
