Awesome looking bread Mike, and maybe we can figure out why the bread attains a more sour taste as it ages.
I just got me a copy of Ed Wood's
Classic Sourdoughs and had to put it to immediate use. My first attempt from the book was Ed's recipe for
San Francisco Sourdough Bread. Now, I don't own any culture other than my own, so I used that and otherwise followed the recipe exactly.
Ed's technique involves building the ferment with 1/2 cup of culture, 1 cup of flour and 1/2 cup of water. This is allowed to ferment for 12 hours at room temp and then another cup of flour and 1/2 cup of water are added and the whole thing is then fermented for another 8 hours. Here's what it looked like after approximately 20 hours.

At this point, the final dough is mixed, using the whole shebang, along with the rest of the flour, water and salt per the recipe. After sufficient kneading, the dough is formed into loaves, either free form or in pans, allowed to proof at room temp for another 3 to 4 hours until sufficiently risen (mine only took 2 1/2), and then baked off. No refrigerator retardation or any of that stuff.
Well, I have to say, I'm pleasantly surprised at the results. I doubled the recipe, made 2 pan loaves and got a great rise. The bread tastes great with a not-too-crusty crust, and I've been wanting to make loaf-bread for a while, for the ease of slicing and sandwich making. Ed also recommends the La Cloche, but for now, I'm happy with this result.