How to Make a Sourdough Starter from Scratch
A sourdough starter is just flour and water that has captured wild yeast and bacteria. It takes about one to two weeks of daily feeding to become strong enough to bake with. Here's the simplest way to make one.
What you need
Whole wheat or rye flour for the first few days (they get a starter going faster), white bread flour or all-purpose flour for feeding, water, a jar and a kitchen scale.
Use a jar that's easy to see through and clean. A rubber band or marker on the side helps you see how much it rises.
A wide-mouth glass jar with a loose lid, a band to mark the starter's height and a thermometer strip. It makes it easy to see when your starter has doubled and is ready to bake with.
Check price on Amazon for Sourdough Starter Jar Kit (opens Amazon)The scale we'd buy first. The display pulls out from under a big bowl so you can always read it, and it holds up to 11 pounds, plenty for any home dough.
Check price on Amazon for OXO Good Grips 11 lb Stainless Steel Food Scale with Pull-Out Display (opens Amazon)Days 1 to 2: Mix and wait
Mix 50 grams of whole wheat or rye flour with 50 grams of lukewarm water in your jar. Cover loosely and leave it somewhere warm, ideally 75 to 80°F.
On day 2, you may see a few bubbles or nothing at all. Both are normal. Stir it and leave it alone.
Adds flavor, color and nutrition. Mix 10 to 30 percent into white bread dough for a heartier loaf, and it's a favorite food for a sourdough starter.
Check price on Amazon for King Arthur Whole Wheat Flour (opens Amazon)A whole grain rye flour for deli rye, pumpernickel and adding deep, tangy flavor to sourdough. Starters love it too.
Check price on Amazon for Bob's Red Mill Dark Rye Flour (opens Amazon)Days 3 to 7: Start feeding daily
Once a day, discard all but about 50 grams of starter, then add 50 grams of flour and 50 grams of water and stir well. You can switch to bread flour or all-purpose flour now, or keep using some whole wheat.
Around days 3 to 5, many starters bubble up dramatically and then go quiet. That's normal. Keep feeding, and the starter will come back stronger.
Days 7 to 14: Watch for a reliable rise
Your starter is ready when it reliably doubles within 4 to 8 hours of feeding, smells pleasantly sour and has lots of bubbles.
If it's slow, find a warmer spot. A proofer, an oven with only the light on or the top of the fridge can all help.
A warm box that holds dough and sourdough starter at the exact temperature you choose. In a cold winter kitchen it turns slow, unpredictable rises into reliable ones, and it folds flat for storage.
Check price on Amazon for Brod & Taylor Folding Proofer and Slow Cooker (opens Amazon)Keeping your starter healthy
If you bake often, keep it on the counter and feed it daily. If you bake once a week, keep it in the fridge and feed it once a week, then take it out and feed it a day before baking.
Don't throw away discard if you hate waste. It's great in pancakes, crackers and waffles.
Frequently asked questions
Why isn't my starter bubbling?
It's usually too cold. Move it somewhere warmer, use a little whole grain flour, and give it time. Some starters take two weeks.
Can I use tap water?
Usually yes. If your water is heavily chlorinated, leave it out overnight or use filtered water.
What's the liquid on top of my starter?
It's called hooch, a sign your starter is hungry. Pour it off or stir it in, then feed it.
How do I know my starter is ready to bake with?
It doubles within 4 to 8 hours of feeding. A spoonful of ripe starter usually floats in water, though this test isn't perfect.
Not sure what gear you actually need?
Answer three quick questions and we'll match you with the right setup for the bread you want to bake.