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How to Revive a Sluggish Sourdough Starter

Fortunately, a little love is all it usually takes to return your starter to a vigorous state.

Few kitchen projects are more rewarding than baking a loaf of sourdough bread from scratch—especially when you’ve used your own home-grown sourdough starter. Nurturing a mixture of flour and water into a live bubbling culture that can leaven bread and imbue it with that trademark sourdough tang can feel almost magical.

Starters require regular “feedings” of fresh flour and water to stay viable. And if you keep up with this maintenance, they can last years or even decades. 

WHY A SOURDOUGH STARTER CAN TURN SLUGGISH

But experienced sourdough bakers know that even a healthy sourdough starter can occasionally lose vigor, exhibiting fewer bubbles and barely expanding after a feeding, leaving it unable to leaven a loaf of bread. This can happen if the starter hasn’t been refreshed regularly enough, or if your kitchen is overly cool (the ideal temperature range is around 70 to 80 degrees; lower temperatures can dramatically slow the growth of the microorganisms). And even if you are on top of the maintenance, sometimes a starter turns sluggish simply for reasons unknown. 

Fortunately, bringing an ailing sourdough starter back to life is simple: You just give it a lot of nutrients by feeding it frequently.  

HOW TO REVIVE SOURDOUGH STARTER

Feed ¼ cup (2 ounces) starter with ½ cup (2½ ounces) all-purpose flour and ¼ cup (2 ounces) water twice daily (approximately every 12 hours) and let it sit, covered with plastic wrap, at warm room temperature. It will be ready to use again when it smells pleasantly yeasty and sweet (rather than sour) and doubles in volume 8 to 12 hours after a feeding.

WHEN TO CREATE A NEW STARTER

If the starter doesn’t revive at all after a day or two of feedings—it doesn’t double in volume 12 hours or even more after a feeding—it is probably beyond saving, and it’s time to start a new one from scratch.

(You should also throw out your starter if you see black, blue, or pink growth on the surface of the starter, which means mold has taken hold; this can occur if the starter is stored in a too-warm environment. However, a clear or grayish layer of watery liquid on top of a starter that hasn’t been fed in awhile is not a problem. It’s alcohol, and it’s a sign that your starter is hungry. Pour it off, discard some of the starter, and feed the rest.)

WHAT TO MAKE WITH LEFTOVER SOURDOUGH STARTER

Once your starter has been reactivated and you’re back to the usual routine of feeding some, and discarding the rest, you don’t have to literally throw out that excess. Instead, collect it in a container and stash it in the fridge. Once you have amassed a cup or two of these leftovers, you can use it to flavor all sorts of things. (Note that sourdough discard can’t actually leaven batters and doughs, so most discard recipes include chemical leavening. Learn more about saving sourdough discard here.)

Have more sourdough questions? Get the answers to 5 common sourdough myths here.  

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