Table of Contents
ToggleABSTRACT
Bioethanol in this study was produced from banana peels using the process of submerged fermentation, Aspergillus niger and Saccharomyces cerevisiae were the microorganisms used which were previously isolated from soil and burukutu respectively.
The fermentation medium was composed of 5% inoculum of A. niger and S. cerevisiae respectively. The ethanol yield after fermentation was determined by checking its specific gravity after distillation and the value obtained was compared with that of a standard ethanol.
The effects of substrate concentration, pH, temperature and time on ethanol yield were determined. After fermentation, ethanol yield was found to be maximum at 8% substrate concentration (9.66%), pH 5.5 (10.52%), 35oC (12.63%) for (3) days.
However ethanol yield was influenced by many factors especially temperature, pH, substrate concentration and time.
1.0 INTRODUCTION
1.1 Background of the Study
Bio-ethanol is an alternative source of energy and has received special attention worldwide due to the depletion of fossil fuels, under such circumstances a novel approach is essential to use renewable substrates such as fruit wastes to produce ethanol (Brooks, 2008).
Banana is one of the major foods that constitute the principal food resources in the world and occupied the fourth world rank of the most significant foodstuffs after rice, corn and milk (INIBAP, 2002).
Banana peels are not considered very useful and are therefore dried, ground, pelletized, and sold to the feed manufacturers at a low price (Mamma et al., 2008).
Though banana peel is a fruit residue, it accounts for about 30-40% of the total fruit weight and contains carbohydrates, proteins, and fibre in significant amounts (Emaga et al., 2008).
Banana peels are readily available agricultural wastes that are under utilized as potential growth medium for yeasts, despite their rich carbohydrate content and other basic nutrients that can support yeast growth (Essien et al., 2005).
Since banana peels contain lignin in low quantities, it could serve as a good substrate for production of value- added products like ethanol (Hammond et al., 1996).
Fermentation is a metabolic process of converting carbohydrates to alcohol or organic acids using microorganisms usually yeasts or bacteria under anaerobic conditions.
However similar process takes place in the leavening of bread and in the preservation of sour foods such as sauerkraut and yoghourt with the production of lactic acid (McGovern et al., 2004).
In order to make the fermentation method cost effective and to meet the great demand for ethanol, research studies are now being directed in two areas namely;
REFERENCES
Arzumanov, T.E., Shishkanova N.V. and Finogenova, T.V. (2000). Biosynthesis of citric acid by yarrowia lipolytica repeat-batch culture on ethanol. Applied Journal of Microbiology and Biotechnology, 53(5):525-529.
Azih, I. (2007). Bio-Fuels Demand: Opportunities for Rural Development in Africa (Nigerian Case Study), A paper presented at the 2nd European Forum on Sustainable Development, Berlin Germany, pp 18-21.
Babatunde, G.M. Machin, D., and Nyvold, S. 1992. Availability of Banana and Plantain Products for Animal Feeding in Roots, Tubers, Plantains and Bananas in Animal Feeding. Proceedings of the FAO Expert Consultation held in CIAT, Cali, Colombia FAO animal production and health paper 95, FAO, Rome.
Babiker, M.A., Abdel, B., Hoshida, H., Ano, A., Nonklang, S. and Akada, R. (2010). High temperature fermentation: how can processes for ethanol production at high temperature become superior to the traditional process using mesophilic yeast. Applied Microbiology Biotechnology, 85:861-867.
Bajaj, B.K., Yousaf, S. and Thakur, R.I. (2001). Selection and characterization of yeasts for desirable fermentation characteristics.Industrial Journal of Microbiology, 41:107 -110.
Barnett, H.L. and Hunter, B. (1972). Illustrated Genera of Imperfect Fungi. Burgress Publishing Company, Minneapolis, p 241.
Be the first to comment