Keeping Your Starter Alive
Once you’ve made a sourdough starter, it’s easy to keep it going for as long as you like. I hear some bakeries in San Francisco have sourdough starters that date back to the 19th century.
Once you’ve made your starter, keep it loosely covered with plastic wrap in a warm place and stir it at least once a day. Developed starter will have bubbles on the surface and may have a thin layer of yellow liquid on top. Stir before using.
After measuring starter out for a recipe, replenish with 3 parts bread flour to 2 parts water and 1 teaspoon sugar. So if you remove 1 cup of starter, add 1 cup bread flour and 2/3 cup water and the sugar. If you don’t use the starter in a week’s time, add an additional 1 teaspoon sugar.
More sourdough tips can be found on Red Star Yeast’s online Lessons in Yeast and Baking.