5 Myths About Sourdough Starter, Debunked | Cook's Illustrated (2024)

With its active bacteria and regular “feeding” schedule, the idea of making sourdough starter scares a lot of home cooks. But when senior editor (and resident bread expert) Andrew Janjigian set out to develop aneasy-to-follow recipe for sourdough starter, we discovered that it’s not so scary at all. You just need flour, water, and time—which is minimal once you get going—for the satisfaction of being able to makebread(and lots of other baked goods) from scratch. So, we’ve decided it’s time to bust some of the biggest myths about sourdough starter, once and for all.

Sourdough starter is a culture of yeast and bacteria, but that doesn’t mean you need to add commercial yeast. In fact, the only ingredients are flour (we found that a combination ofwhole-wheatandall-purposecreate the optimal starter) and water. The yeast and bacteria are already present in the flour, butthe process of making and maintaining a starterwakes them up and feeds them regularly so they can continue to grow.

The key to sourdough starter success is using water without chlorine, which can cause the starter to die. While bottled water is chlorine-free, you can also use filtered tap water for our sourdough starter recipe.

While some people lovingly name their sourdough starters, that doesn’t mean you need to feed it as often as your four-legged friends. In the early stages of developing the starter, you should feed it every 24 hours, but after 10 to 14 days, you can move to the maintenance phase, keeping your starter in the refrigerator and feeding it just once a week. And if you do miss one of the daily feedings at the beginning, don’t worry—just be sure not to go more than 48 hours without a feeding.

Some sourdough starter recipes suggest using a temperature-controlled bread proofer to create the right environment for the bacteria in the flour to flourish, but this isn't really necessary. As long as your kitchen is about 70 degrees—what we consider to be room temperature—you can leave the starter on the counter for its five-hour post-feeding resting period and then store it in the refrigerator. As for the rest of the steps in Andrew’srecipe, ordinary kitchen equipment is all you’ll need.

As a rule of thumb, sourdough starter is ready for baking when it’s doubled in size, about 18 to 24 hours after it’s been fed. If you think it’s good to go but want an easy way to be sure, all you need to do is drop a spoonful of starter into a bowl of water. If the starter floats, you’re ready to bake, but if it sinks, you should wait another hour and try again.