A Prost to Yeast

So I haven't posted in a while, shame on me. This will be short as I am headed to bed I have early morning lab tomorrow. So today I made a nice loaf of bread. I think it is one of the best looking loaves of bread I have made so far, so I took a picture of it to share with the world... of people who read this blog. My roommates approve of the bread which is good, because I probably wouldn't eat the who thing before it got hard.
I am working on a new batch of bread, some sour dough bread. I got some sour dough starter from The Cheese Board in Berkeley CA. The Cheese Board has just about every conceivable cheese which can be imagined. A really unique place. I had the opportunity to visit the store when it was closed and had a private sampling of various cheeses. Absolutely fantastic, I wish the friend of a friend who made it happen many thanks.
Having no idea how much starter to used in a batch of bread I used about half of my container of starter, or about three fourths of a cup or about a 175ml, how ever you want to kick around the volume. I took the remaining starter and split it up into two containers, one rather big. I mixed up three cups of flour water for the big container and about a cup of flour water for the small container. I added them to the culture mixed them up and put them on top of the bookcase in my roommates room (the warmest place in the house) They have been there since two this afternoon. I just moved the smaller container to the fridge as it was showing signs of a strong fermentation.
Yeast and a few strains of bacteria are the work horses of sour dough starter. You probably already knew that, worth mentioning though. Now I don't know what yeast does to produce the sour part in the mixture. Possibly the bacteria act on the by products of the yeast's respiration, or possibly a combined effort. I really don't know, but I intend to ask my brewing/food science professor this very question and I will get back to you. Yeast is just one, and the major thing that make bread kick ass in my book. Fermentation done by yeast is so cool, with the production of alcohol and CO2 from simple sugars, yeast is the unsung hero of modern society. With out it there would be no alcohol (well for the most part) and bread would be flat, which is not a bad thing but would get a bit boring after a while. Next time you eat a sandwich or imbibe a beverage of a refreshing nature, think of yeast!