Optimization of ethanol production from <i>Garcinia kola</i> (bitter kola) pulp agrowaste

Abstract

Optimization options for production of ethanol from bitter kola (Garcinia kola) pulp wastes were investigated. The methods are degumming, saccharification, acid hydrolysis, alkaline hydrolysis. Degumming was effectively achieved at 96 h of saccaharification. The concentration of reducing sugar for the treated sample (acid hydrolysed and saccharification) and control sample (saccharification) was
maximum at 144 h (86.2 g/100g) and 96 h (31.5 g/100 g), respectively. Ethanol yield from treated sample and control sample using baker’s yeast was maximum at 120 h (70.7 g/L) and 192 h (29.3 g/L), respectively. Alkaline hydrolysis with 0.25 M sodium hydroxide has no significant effect on concentration of reducing sugar and ethanol yield. Acid hydrolysis with 2.5 M sulphuric acid and saccharification using Aspergillus niger are better methods for optimizing ethanol production from bitter kola pulp waste. Solar drying of the bitter kola pulp waste significantly enhanced ethanol
production.