Comparative study of two raw media and two fermentation methods for ethanol production by local and imported strains of saccharomyces cerevisiae

ABSTRACT

Two fermentation media and two fementation methods were compared for their efficiency for ethanol production by local and imported strains of Saccharomyces cerevisiae The result appeared that using stil culture method for alcohol production from date juice extract [24 prix] The yield was 13.5% alcohol and 4% sugar residue after 12 hrs for local strain. Whereas 12.1% alcohol and 5.4% sugar residue for imported strain. In lab fermenter produced alcohol was 15% and sugar residue 0.4% for local strain, and 13.3% alcohol 3.6% sugar residue for imported strain. Using molasses as fermentation medium [23% sugar] in still culture method, produced alcohol was 9.6%, 7.8% and sugar residue was 7.8%, 8.2% for local and imported strains, respectively. While in lab-fermenter, produced alcohol was 8.5%, 7.9% and sugar residue was 11.6%, 12.2% for local and imported strains, respectively. It was stated in this work that Date juice was better than molasses and lab-fermenter better than still culture method for ethanol production. In all these cases isolated local strain was more efficient than imported european strain for ethanol production. Other fermentation products methanol, propanol, and acetylaldehyde was determined by gas chroniatography in both fermention media