Comparative Study of Bioethanol Production from Irish and Sweet Potato Peels by Hydrolysis and Fermentation Processes using Saccharomyces cerevisiae

Abstract

The quest for green and sustainable sources of energy has led to various studies on the production of biofuels such as bioethanol from different agricultural materials. This study presents a comparative analysis of bioethanol produced from Sweet and Iris potatoes using simultaneous saccharification and fermentation (SSF). 5.00, 10.00, and 15.00 g each of the Sweet and Irish potato peels were hydrolyzed using dilute acid (5% H2SO4). A dried baker’s yeast strain (Saccharomyces cerevisiae) was subsequently introduced to ferment the substrates for 7 days. The bioethanol yield, average bioethanol yield, density, and proximate composition of the substrates were determined. The yield of bioethanol for Sweet potato peels at 5.00, 10.00, and 15.00 g were 43.50, 64.50 and 82.00 cm3 while for Irish potato peel at 5.00 , 10.00 and 15.00 g were 22.00, 41.50, and 59.00 cm3

, respectively. The average bioethanol yield for Sweet potato and Irish potato peels were 63.33 and 40.83%, while the density for Sweet and Irish potato peels were 0.853 and 0.891 g/cm3

, respectively. The proximate composition for Sweet potato peel was 5.10±0.01% moisture, 4.00±0.023% ash, 2.99 ± 0.044% lipid, 3.50±0.03% fiber, 7.00±0.05% protein, and 77.41±0.01% carbohydrate while for Irish potato peel were 8.75± 0.63% moisture, 3.55± 0.05% ash, 4.48± 0.03 lipid, 4.50± 0.55% fiber, 4.38± 0.67% protein and 74.34±0.15% carbohydrate. Therefore potato peels can be harnessed as a potential feedstock for bioethanol production with Sweet potato peel having a higher yield of bioethanol compared to Irish potato due to higher carbohydrate content.