Yeast? I Thought You Said Weast: The Effect of Salinity and Agitation on the Anaerobic Fermentation Rate of Saccharomyces cerevisiae

Abstract

The anaerobic fermentation pathway of Saccharomyces cerevisiae is commonly utilized within the brewing, baking, and biofuel industries; however, the baking industry imposes saline conditions on S. cerevisiae to ensure controlled fermentation growth. Additionally, agitated growth conditions are utilized for increased yeast reproductively and respiration. Therefore, this research project is focused on determining the comparative effects of variable agitation on yeast fermentation with and without the presence of salt. It is hypothesized that CO2 production will increase with increasing agitation due to increased nutrient circulation for respiration; however, CO2 production will decrease with increasing agitation in the presence of salt due to increased dehydration rates of S. cerevisiae. Through preparing nine saline and nine control yeast biochambers and growing three of each group under 0 rpm, 1.5 speed, and 3 speed agitation conditions, the CO2 production was analyzed to determine the comparative fermentation rates. The data did not support our hypothesis, which could indicate support for the intermediate disturbance hypothesis.