The Effects of Sugar Complexities on Ethanol Production in Yeast (Saccharomyces cerevisiae)

Abstract

The effects of different types of sugar complexities on the brewing process was examined by measuring ethanol output from fermentation of Saccharomyces cerevisiae. During the brewing process, yeast is used to convert glucose to carbon dioxide and ethanol. This prompted the question of whether or not more complex sugars with more glucose and other natural sugars would maximize ethanol production. To test our hypothesis, we used glucose, sucrose (formed from glucose and fructose), and rice sugar which is formed from the monosaccharide glucose and the disaccharide sucrose to see which sugar would result in more ethanol production and therefore a higher performance. Our hypothesis is not supported, and we found that the higher sugar complexities did not correlate to an increase in ethanol production. As the sugar became more complex, less ethanol was produced and final sugar percentage decreased. This could be due to our more complex sugars, sucrose and rice sugar, being harder for the yeast to utilize during fermentation than glucose.