Today's installment is very simple. We are going to "feed" the starter. This involves removing, and discarding, half the mixture; then adding 1/2 cup of flour and 1/2 cup of water. This step is going to be done every 24 hours, until the started is ready.
I will show you my starter when it's ready, but since this can happen anytime between 2 and 7 days, you need to know what to look for. Sometime between now and never, your mixture will start developing lots of little bubbles, and start giving off a somewhat pleasant sour or beer-ish smell. The starter may also develop a thin bubbly froth on the surface that will return even after you stir it in. The photo here is my starter on day 3. It's getting close, but I'm going to feed it again, and decide tomorrow if it is ready.
The timing of this whole process depends on the batch of flour you're using, the temperature (75 degrees is ideal, but most of us are cooler than that), and the amount of wild yeast present (they really mean it here in San Francisco, when they say, "there must be something in the air."). So, keep repeating the steps you see in today's video until you think your starter is ready. I will post updates on my starter as things develop. Stay tuned!
Note: if your starter gets a strong, spoiled odor, toss it out and start over. You may have something else growing besides wild yeast. If nothing happens after a week, then you should also start over with another type of flour. Many people add some wheat or rye to the first starter since it has more yeast in it. But, I just didn't want you to buy a whole bag of flour for nothing, and we are going to use the unbleached bread flour to make the final loaves.