Effects of Different Types of Sugar on Carbon Dioxide Output in Yeast

Abstract

Saccharomyces cerevisiae is a species of single-celled organism often used to make foodstuffs such as bread or beer.  When S. cerevisiae ferments, it consumes sugar and produces ethanol and carbon dioxide; however, more research is needed into how different kinds of sugars may affect this process.  This research set out to find how different types of sugars affect the fermentation rate of yeast.  It was hypothesized that sucrose would have the highest rate of carbon dioxide output and thus the highest rate of fermentation, while corn sugar would have the second-highest rate of fermentation, and rice sugar would have the lowest rate of fermentation.  Four trials were run for each of the three sugars, during which sugars were supplied to S. cerevisiae and carbon dioxide levels were collected over a period of five minutes.  The results were that sucrose had the highest rate of fermentation (M=329.75; SD=98.30), meaning it gave off the greatest amount of CO2 during our experiment. Rice sugar had the second highest rate of fermentation (M=267.35; SD=67.31), and corn sugar had the lowest rate of fermentation (M=254; SD=58.44), which partially confirms the hypothesis.  These findings could have implications for industries that utilize yeast in that it could help maximize production rates.