November 20, 2012
Lab# 9: Applied Mycology
Introduction: Back in the day, the people of the San Francisco gold rush were served sourdough biscuits and bread. This wild yeast based bread was later to become famous, for its slightly tart taste. The bread was created from what is called a starter, where wild yeast is allowed to grow to replace store bought yeast, I found in this lab that my home brewed yeast tasted fresher and made the waffle texture much airier. I also learned a lot about making the starter itself, like if you’re at a higher altitude then you use less flour to make the yeast grow, and that you can typically only rise your bread once because the wild yeast is weaker than the store bought yeast. I stirred the mixture every four hours for the first four days; I also left it outside of the refrigerator until day five, just to make sure the yeast would be able continue growing. I fed him (I later named him Bruce, apparently it can last for a hundred years, he’ll outlive me!) every day before I put it in the fridge, he seemed to be happy and bubbly by day three, with a sticky bubble gum like texture by day five. I made an “overnight sponge” with my waffle recipe and it did not require me to activate the starter, but I plan on making dill bread so I’ll get to retry the activation process with that. My brother was home for thanksgiving so he became my taste tester, he said the sourdough were “fluffier” so I’m not sure if that was actually the starter or the overnight sponge treatment but they turned out well anyway. Abstract: The purpose of this lab was to understand how yeast was cultivated prior to the use of commercial yeast. I was able to taste a notice difference in my homemade waffles vs. Krusteaz box mix waffles. This could be just because Krusteaz doesn’t use the highest quality products, but the homemade ones did actually weigh less (used a small gram scale). I enjoyed seeing how Bruce went...