The Rate of Ethanol Production of Saccharomyces cerevisiae with Three Types of Sugars

Abstract

 Saccharomyces cerevisiae, also known as baker’s yeast, uses sugar during fermentation to produce ethanol that can be used to produce biofuels. This observation led us to question if ethanol production would be increased in baker’s yeast with a monosaccharide, disaccharide, or polysaccharide. From this question, the hypothesis was formed that ethanol production in baker’s yeast would increase with a monosaccharide. This hypothesis was tested by preparing 250 mL bio-chambers individually with a monosaccharide (glucose), disaccharide (sucrose), or polysaccharide (starch) and measuring their ethanol production. The ethanol output was measured every 15 seconds for 10 minutes after an adjustment period. The results of these tests showed an increase in ethanol production with the monosaccharide and disaccharide, and a decrease in ethanol production with the polysaccharide. These results show that in order for baker’s yeast to be a source of ethanol for biofuel production, it would need to have a monosaccharide or disaccharide. Future research can also be done to determine what concentrations of these sugars can be used to maximize ethanol output.