The science of sourdough baking begins with a starter made from simple ingredients that functions as the yeast agent for rising bread. Once matured, a starter can last for years if refrigerated between baking in order to slow the growth of the yeast. However, a refrigerated yeast starter still needs to be fed or the production of alcohol – a clear to light-brown liquid known as "hooch" – will develop and may need to be decanted.
After One Week
After one week of refrigeration, your starter will most likely appear lifeless and separation between the liquid and solids will have occurred. This is normal, and a few hours at room temperature along with a feeding will revive your starter. Add equal parts of water and flour, stir the mixture and allow it to stand loosely covered at room temperature – ideally between 75 and 80 degrees Fahrenheit – to give the yeast a chance to “feed.” You can use your revived starter to bake with, but to keep your starter going, measure out at least 1 cup and store it loosely covered back in the refrigerator.
After Two to Three Weeks
If you forget to feed your starter and a few weeks go by, you'll notice the presence of hooch. This normal alcohol by-product is produced by your yeast and indicates that a feeding is necessary. Remove the container from the refrigerator, stir the hooch back into the mixture and proceed with a feeding as described in the previous section. If you are not planning to make bread and have more starter than you can comfortably store, decant what you don’t need by pouring out any extra starter, remembering to stir first, and refrigerate the rest. Extra starter can be used in recipes for pancakes, muffins and brownies, or simply washed down the drain.
After One Month or More
If your starter goes for a month or more without feeding, you’ll notice more of the liquid hooch. If your starter is looking too thick, the liquid can be stirred back in; if the starter is looking thin or watery or you think there is too much of the hooch, decant. Pour the liquid off and replace the lost liquid with room-temperature water and proceed with a feeding. If the liquid hooch is an off-color such as pink or orange, or any mold develops on the container, discard the starter.
Safely Storing Your Starter
To clean your storage container, pour the starter into a non-metal bowl before feeding, then wash and dry your container. This prevents any unwelcome bacteria from developing. Using a wide-mouth glass container is acceptable, but caution should be used when refrigerating glass due to the danger of built-up gases. Leave enough room in your storage container for your starter to double in volume, and keep the cover loosely fitted to allow for air exchange.
- Mother Earth News: Creating Homemade Sourdough Bread From a Starter Mix
- What’s Cooking America: Sourdough Bread Starter
- The Old Fashioned Recipe Book; Carla Emery
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