All About Sourdough

Photo by mondiano/iStock / Getty Images
Photo by mondiano/iStock / Getty Images

Sourdough, culture, levain, starter, chef, wild yeast....

All are terms for fermented flour that is used to leaven baked goods. Sourdough can be made by mixing flour and water and allowing it to ferment.

The microbes responsible for the fermentation are already present on the grain and in the environment around us. There is no need to add yeast. (Nor to supplement the starter with sugar, fruit, or juice as some believe.) In fact, adding packaged yeast to a sourdough culture means that it is no longer sourdough because the yeast strains in the package will overtake the wild yeast population. 

Caring for a sourdough culture:

  • Sourdough needs to be 'fed' regularly. Just like animals, a culture needs food and moisture or it will die. Adding more flour and water to your culture 'refreshes' it and allows it to keep living.
  • Discarding old starter. As sourdough ferments, the bacteria present in it create acids (lactic and acidic, if you want to get scientific). Too much of these acids will kill the yeast. Before feeding your starter, discard some or most of the starter already in the container in order to reduce the amount of acid. You can pour it into the compost or into a separate container and store it in the fridge if you want to save it and use it (I recommend for pancakes).
  • Storage. There are options for how to store a starter depending on how often you plan to use it and how much feeding you are willing to do. The colder the environment a starter is kept in, the slower fermentation happens. Keeping starter at room temperature or higher will require feeding it every 12-24 hours. If you plan to use it to bake bread every day or every few days, or you just don't mind feeding it every day, this is how it should be stored. If you plan to use it less often, don't want to feed it as often, or are going out of town and need to go without feeding it for up to a week, store the starter in the refrigerator. Always feed the starter and allow it to stay out at room temperature for about an hour before moving it to the fridge.  
  • An additional source for information and sourdough recipes: Wild Yeast Blog