How to Feed Sourdough Starter
Learn how to feed your sourdough starter to keep it healthy and happy! Here are instructions on how to feed starter by weight, or by volume measurements. Included are tips on how often to feed it, flour options, and also the importance of temperature.
Feeding Starter by Weight (1:1:1)
- 100 grams sourdough starter
- 100 grams water (room temperature to lukewarm, and non-chlorinated filtered water recommended)
- 100 grams flour *Note that using whole wheat or rye flour (instead of white) can help increase starter activity.
Feeding Starter by Volume (1:1:2)
- 1/2 cup sourdough starter
- 1/2 cup water (room temperature to lukewarm, and non-chlorinated filtered water recommended)
- 1 cup (scant, just under a cup) flour
- *Scale up as needed to maintain a larger starter. Simply keep similar ratios
The act of "feeding" your sourdough starter is simply adding more fresh flour and water to an existing starter. This may be after you take some of your starter to use in a recipe, in order to build its volume back up. Or, in order to activate a dormant starter to prepare it for baking (to reach "peak activity), you need to discard a portion of it and then add fresh flour and water - aka, feed it.
Starters need routine feeding to stay alive. Even if you aren't actively baking, you'll need to feed your sourdough starter on occasion. The frequency depends on how you store it. Starters that are stored in a refrigerator can be fed every couple of weeks (or even up to every couple of months, once mature and established). On the other hand, starters stored at room temperature must be fed every day or every other day.
Where you feed your starter is up to you. Some bakers dump their starter, fresh flour and water in a clean bowl to mix/feed it every time, and then transfer it to a clean container. Others simply mix more flour and water into the same container the starter is already living in. Either way, I suggest to keep the sides of your stater container fairly clean, and change it out or wash it on occasion. Built-up gunk on the sides of the container can more easily lead to mold.
Preparing to Feed
Warm up: If you choose to keep your sourdough starter in the refrigerator, allow it to warm to room temperature for several hours before feeding. We generally take ours out of the fridge the night before we want to make sourdough, then feed it in the morning. Avoid adding cold water, which will also slow it down.
Discard a portion: Stir to knock out any air, and then remove some starter from its container. Leave enough behind (amounts described below) to mix with fresh flour and water. Use the "discarded" starter in a recipe, feed it to your chickens, or compost it.
Now, add more fresh flour and water to the remaining starter, either following the "weight" or "volume" instructions below
How to Feed Sourdough Starter by Weight
To feed a sourdough starter using weight, simply combine equal parts existing starter, flour, and water. For example, 100 grams of each. Or for a larger starter, 200 grams of each.
It's very helpful to know the empty weight of your starter storage container, so it's easy to determine how much starter you have left after discarding. You will need a kitchen scale.
How to Feed Sourdough Starter by Volume
To feed a sourdough starter using conventional volume measurements, simply combine 1 part leftover sourdough starter, 1 part part water, and just under 2 parts flour. For example, 1 cup starter, 1 cup water, and nearly 2 cups of flour. (The ratios are different with this method because water weighs more than flour.)
In our kitchen, we maintain a fairly small container of starter. Therefore, our routine feeding is: add 1 scant cup flour and 1/2 cup of filtered water to approximately ½ cup to ¾ cup starter left in its storage container after discarding. Honestly, we eyeball/estimate the amount of starter left in the container, rather than taking it out to measure.