Faculty Sponsor: Dr. Wessner
Sour ales are produced through introducing one or a combination of fermenting agents such as lactic acid producing bacteria. We isolated these microorganisms from four different foeder tanks that make sour ales at D9 Brewery, a local microbrewery in Cornelius, and grew them both on general media plates (tryptic soy agar) as well as plates containing a selective medium, MRS (De Man, Rogosa, and Sharpe) agar. MRS is a selective medium that is designed to favor the growth of Lactobacilli (lactic acid bacteria). The growth of microorganisms on both these plates were compared. The pH of tryptic soy broth (TSB) was manipulated to three different pHs and the growth of the microorganisms from each of the four different foeders was measured over a 48 hour period to determine growth curves. These growth curves allowed us to further classify the microorganisms that are present in the foeder tanks as well as to determine pHs the microorganism were able to grow the best. We also did a sequence analysis of the bacteria to further characterize them.