You all know that I love a good kitchen experiment. In my quest to use less and less yeast in my home-baked bread, I thought of baking sourdough bread again. I've made sourdoughs before, using flour, water, and a bit of yeast. But you know, the old-time way to make a sourdough starter uses only water and flour. I was really curious just how difficult it is to get a starter going the old-fashioned way. And with the current situation of limited yeast availability, it seemed like a good time to try this out.
I didn't want to waste a lot of flour, so I began with a very small amount of good, unbleached flour (I used King Arthur Unbleached All-Purpose Flour). Filtered water would have been preferable, as chlorine might inhibit some fermentation activity. However, using what I had at home suited the nature of this experiment. So, tap water it was.
In a small glass bowl, I stirred about 1/4 cup of flour into lukewarm water, enough to make a thick pancake batter consistency. Then I placed the bowl in the oven with the door closed and the light on. I left it like this for 24 hours, without removing it from the oven or turning off the light. The electric light in the oven keeps it quite warm, without being too hot for the fermentation.
By the following morning, the top of the batter looked crusted over. I removed the bowl from the oven and could see through cracks in the dried top layer that there were bubbles underneath.
The batter also smelled sour! I lifted the crusted surface and could see lots of bubbly activity going on below! How exciting -- a real sourdough starter without relying on commercial yeast to get it going.
I warmed a bit more water (about 1/4 cup) to just slightly warmer than room temperature and stirred this into my baby starter along with more flour (another 1/4 cup) and placed the bowl back in the oven with its light on. I checked on it about 10 hours later. It looked flat with layer of liquid on top. I stirred it up and could see bubbles forming right away. I fed it a little more flour and water and placed it back in the oven. Within an hour, it was bubbly. I suspect that I'll need to feed my starter twice per day for about 6 to 8 more days before it will be ready for a batch of bread. When the starter has grown sufficiently and is very active (sometime next week), I'll be baking a batch of San Francisco sourdough bread, using the recipe in this post.
No need to buy that overpriced yeast on ebay or Amazon. I can bake bread without any commercial yeast at all.
