Does the time that salt is added affect yeast growth?

Abstract

Yeast uses fermentation to create energy to power growth. Salt has been shown to lead to less fermentation than sugar (Florence et al. 2016). In this experiment, we decided to test whether or not the time that salt is added to a yeast solution has any effect on yeast growth. We hypothesized that salt added initially to a yeast solution would inhibit growth more than salt added later. Our experiment involved the same salt concentration added to yeast solutions at the beginning and halfway through a period of one hour. Our results support our hypothesis that longer exposure to salt would lead to lower yeast cell growth, however we were not expecting for the salt to lead to more yeast growth than the control. We believe that more research is needed to better understand the link between salt and yeast cell growth. However, this study helps to support that NaCl itself does not inhibit yeast growth. Our results may help bakers decide the best time to add salt depending on their desired yeast performance.