Day-by-day instructions

Day 1

• Combine 1 cup (113 grams) of whole wheat or rye flour with ½ cup (113 grams) of water thoroughly in the non-reactive container. Leave the container out at room temperature (at least 70 degrees) for 24 hours. Cover the container with cheesecloth and a rubber band, or opt for a jar with a lid that is designed for air circulation without drying out the starter.

Days 2 and 3

• Discard half the starter (about 113 grams or ½ cup of the mixture). You’ll be discarding quite a bit of starter over the next few days, which you can either reuse to make pancakes or compost. To the remaining starter, add 1 cup (113 grams) all-purpose flour and ½ cup (113 grams) water. Combine and let sit at room temperature for 24 hours.

Day 4

• You should notice some bubbles and will want to start feeding your starter every 12 hours now. Continue feeding by weighing out 113 grams starter, discarding the remainder, and feeding with 113 grams all-purpose flour and 113 grams water. Mix, cover, and let rest for 12 hours before repeating again.

Day 5

• Repeat the same 1:1:1 ratio of starter, flour and water feeding every 12 hours. By the end of Day 5, you may have an active sourdough starter. A sourdough starter is ready to use when you see lots of bubbles on the surface and the mixture has doubled in volume. An active sourdough starter will also smell a little bit fruity or tangy.
• If your starter hasn’t doubled in volume and is not bubbly, repeat the process of discarding and feeding every 12 hours until it does. The process often takes up to a week, so continue feeding for a few extra days if it hasn’t doubled yet — patience is key here.

How to store sourdough starter

• Once you have an active sourdough starter that has doubled in volume, you can begin to store it in your refrigerator, covered and reduce the feedings to about once a week.
• Feeding your sourdough starter
• To maintain your sourdough starter, you should feed it at least once a week (even if you’re not using it to bake).
• Before you bake with it, you must revive your starter first. Sourdough starter cannot be used straight from the fridge. The night before you plan on baking a loaf of sourdough bread, remove the starter from the fridge and feed it with fresh flour and water, then leave it out (covered) at room temperature.
• Either way, the feeding process is the same: weigh out 113 grams or ½ cup of starter and discard the rest. To the remaining mixture, add 1 cup (113 grams) all purpose flour and ½ cup (113 grams water). Mix and let rest, covered, until the mixture has doubled. Depending on the warmth of your house and how active your starter is, this could take as little as an hour or two, or up to 12 hours. If your house is a little chilly, you can speed up the process by keeping your starter in the oven with the light on. Be sure to leave a note to let people know not to turn the oven on and ruin your starter by baking it.