Sugar Rush: The Effects of Sugar Concentrations on CO2 Output in Saccharomyces cerevisiae

Carley Schroeder, Kyley Moore, Jasmine Williams, Brayden Stewart, Pierce Wilkins


Anytime bread is baked, it is done using yeast such as Saccharomyces cerevisiae, a unicellular organism that, through fermentation, consumes sugar and releases carbon dioxide (CO2), which causes the bread to rise (Hewitson & Hill 2019). Glycolysis plays a large role in anaerobic yeast fermentation, so the amount of sugar added to yeast can have a large effect on yeast production. We tested different concentrations of dextrose to find which concentration was the most efficient between 1%, 2%, and 3%. We hypothesized that the 2% would have the most success. We tested the CO2 output of each concentration with a CO2 probe for five-minute intervals of three trials.  While the 2% concentration did consume the most amount of dextrose, we found that the 1% solution showed the greatest efficacy. This shows that, when using dextrose, S. cerevisiae will be the most productive in a 1% dextrose concentration.

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