This basic recipe for sourdough starter relies on wild yeast and bacteria that are naturally present in the air settling on the mixture. It works fastest in a kitchen where lots of bread baking has happened over the years. Depending on factors such as the weather, it may take up to two weeks to see the full, bubbly effect.
Ingredients
- 2 cups all-purpose flour
- 2 cups water
Equipment
- A bowl or other container, at least 1 quart (1 liter) in size. It should be made of a non-reactive material, such as plastic, glass, or stainless steel (but not copper, cast iron, etc.)
- Spoon or whisk for stirring
- Clean dish towel or cheesecloth
Procedures
- Mix ½ cup of the water with ½ cup of the flour in a bowl until smooth.
- Cover the bowl with a dish towel in a warm place (~70–80 °F; 20–27 °C) and place in an open, clean spot on the counter to catch wild yeast floating in the air.
- On the second day, add ½ cup flour to the mix and enough water to make it like a thick pancake batter. It should have had a few bubbles on the surface before you fed the mix.
- On the third day, the starter should have a lot of bubbles all over coming up from deep inside. Feed it again with ½ cup flour and water.
- On the fourth day, it should be very bubbly. You can start making bread with it, and then feed the remaining starter again with flour and water.
Maintenance
The traditional maintenance program mixes together equal parts of starter, flour, and water each day (or each week, if you store it in the refrigerator).
For example, if you want to add ½ cup flour and water each day, then combine them with ½ cup of the starter, and “discard” any excess starter. Alternatively, for a no-discard approach, if you have 2 cups of starter, you can add 2 cups of flour and 2 cups of water each day; however, this approach can result in having an excessive amount of starter in a fairly short time.
“Discarding” can be taken literally, but the “discarded” portion can be used in baked goods.
Notes, tips, and variations
- You must use clean water that is safe for drinking. Some people prefer to use filtered water or to sterilize the water by boiling it and cooling it every day. This extra effort is unnecessary in most of the developed world.
- You can use whole wheat or other traditional bread flours (e.g., rye) for part of the all-purpose flour in this recipe.
- The point of covering the bowl with a dish towel or cheesecloth is to let air circulate inside the bowl, but to keep any passing houseflies or curious pets out. Do not use plastic wrap or put a lid on the bowl.
- The starter is ready when it becomes very bubbly and has a much larger volume in the 4–12 hours after feeding it. If you don’t have a lot of bubbles by the fourth day, then you may need to keep going for a few more days (or start all over with a clean bowl).