Effect of Acidic pHs on CO2 Production in Baker’s Yeast

Jordyn Glover, Jude Birkenholz, Kendyl Doss, Alyvia Fox, Emma England


Fermentation is the process in which Saccharomyces cerevisiae, commonly known as yeast, breaks down sugar to get energy and produces CO2 and ethanol as byproducts. Because of its products, fermentation of yeast is an important process in the baking and brewing industries. Yeast’s ability to ferment is affected by many environmental factors, such as pH, and to examine the effect of pH on fermentation, we measured the CO2 production of yeast in three different pH environments: control (pH 7), pH 3, and pH 5. Our results showed that yeast produces more CO2 at lower pHs. This raises the question of whether the solution used to grow yeast should be more acidic than current industry standards.

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