DI-tching the Tap: Deionized Water’s Effect on Carbon Dioxide Production of Baker’s Yeast (Saccharomyces cerevisiae)

Abstract

Baker’s yeast, scientifically known as Saccharomyces cerevisiae, is an important ingredient in many baked goods as well as alcohol production, both for beverages and industrial ethanol, making it one of the most essential microorganisms that humans use (French 2021). This means that it is vital to know what conditions best allow for yeast growth. This led our group to question whether deionized or tap water would be more effective. Deionized water is essentially tap water that has had the majority of minerals removed (Lenaburg et al. 2016). Based on the fact that deionized water is more stable, we hypothesize that it will be more efficient in growing yeast. In order to test our hypothesis, we ran a total of 16 trials, 8 control trials with deionized water and 8 experimental trials with tap water. We did this by measuring the CO₂ produced by the yeast in both mixtures. In order to understand the results, we averaged the data for tap water and the data for DI water respectively. After conducting the experiment and analyzing the data, we found that the deionized water had an average CO₂ output of 1733.303 ppm and the tap water had an average CO₂ output of 1844.645 ppm. This means that our hypothesis was not supported because deionized water produced less CO₂ than tap water.