Abstract:
Fossil fuels are non-renewable, and their excessive use has resulted in a lot of environmental problems. There is an urgent need to develop alternative renewable and environmental friendly energy sources. The objectives of this study were to: (i) compare the carbohydrate contents of some corn varieties grown in Nigeria. (ii) determine their amylose : amylopectin ratios. (iii) compare ethanol productivities and yields from the corn varieties, and (iv) make pragmatic economic analysis of corn ethanol production in Nigeria. Amongst the four corn varieties, Zea mays var. Indurata gave the highest (P<0.05) starch content of 64 % followed by Zea mays var. Praecox with 62 %, Zea mays.var Indentata with 60 % and Zea mays var. Ceratina with 57 %. Statistically, the starch contents of the corn varieties can be ranked as Zea mays var. Indurata > (Zea mays var. Praecox = Zea mays var. Indentata) > Zea mays var. Ceratina. The ethanol concentration obtained from 10 g of corn flour and 10 g of koji were (g/l) 24.70, 23.11, 22.38 and 21.30 for Zea mays.var Indurata, Zea mays var. Identata and Zea mays var. Ceratina, respectively. Fedbatch fermentation gives higher ethanol concentration of 47.08 g/l in 9 days. Economic analysis showed that with Zea mays var. Indurata at 6,000/100 kg market price, the cost of production is N276.42/L as at 2012. However, if the market price of corn can be reduced to N2,000/100kg, the cost of production will decrease to N92.00/L, which is profitable provided that the current fuel subsidy on fossil fuel is removed.
