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If you’re just learning to bake sourdough bread, you might be confused by all the terms bakers casually bandy about. Ripe starter, autolyse, hydration, banneton … it’s like a whole different language. One of the most common terms — and the most confusing — is discard. What exactly is sourdough discard? And what the heck are you supposed to do with it?

We’re here to answer all that and more.

What is sourdough discard?

When you feed sourdough starter, you must remove a portion of the starter to make room for the flour and water you’re adding to the mixture. Sourdough discard is the portion of starter that gets removed as part of its routine maintenance.

Bowl of sourdough starter on scale next to a crock with sourdough starter Photography by Rick Holbrook; food styling by Kaitlin Wayne
Sourdough discard is the portion of starter you don't feed during routine maintenance. You can choose to dispose of it or bake with it. 

Why do you discard sourdough starter?

Bakers often ask us, “Do I really need to discard my starter?” And the answer is yes. Regularly discarding a portion of your starter and refreshing it with flour and water keeps the microorganisms in it healthy, happy, and thriving — and healthy starter translates to better bread. And if you didn’t remove a portion of the starter when you add flour and water, you'd quickly have way, way too much starter.

But just because you remove sourdough discard, that doesn’t mean you have to actually throw it away. You can bake with it, either immediately or at a later date, and make everything from bread to cookies to granola and more.

What to do with sourdough discard

If you can’t bear the thought of tossing your discard into the trash bin or compost (psst: never put it down the drain!), you can use it in other ways. We have a whole collection of Sourdough Discard Recipes that you can bake with your sourdough discard; in these recipes, discard adds flavor but doesn’t do much in the leavening department. Some of our favorite sourdough discard recipes include:

You can even make bread with sourdough discard. We have several recipes that can be made with unfed sourdough, instead of the typical ripe starter. Just note that it’s best if your starter has been fed at least once in the past week; a neglected starter won’t make great bread. Try sourdough discard in these bread recipes:

Sourdough discard can also be used to start a new sourdough starter. You can gift the discard to a friend looking to start their own sourdough journey; all they need to do is feed it with water and flour to have a thriving starter of their own. See more here: You finally got a sourdough starter. Now what?

How to add sourdough discard to any recipe

You can use sourdough discard in any recipe calling for “unfed” or “discard” sourdough starter, but it can also be used in recipes that don’t call for it.

Because sourdough starter is made of flour and water, think of it as a replacement for some of the flour and water (or milk) in your recipe. The key is that the recipe must include enough liquid and flour for you to substitute in sourdough discard instead. A cookie recipe, for instance, likely wouldn’t be a good choice, since cookies don’t typically have a significant amount of liquid. But muffins, snacking cakes, quick breads, and pancakes all usually include enough liquid for the substitution to work. These are also generally forgiving recipes that adapt well to some tinkering; this is important, because adding sourdough discard will impact a recipe and potentially alter the final result.

Remember, you’re substituting starter for some of the recipe’s flour and liquid, not simply adding: When discard starter goes in, an equivalent amount of flour and water must come out to preserve the recipe’s balance of ingredients.

How to add sourdough discard to a recipe: Because sourdough starter is usually equal parts flour and water by weight, take the amount of discard starter and divide it by two; that is how much flour and water you’re subbing for. For instance, if you have 100g starter, that is equal to 50g flour and 50g water. Deduct those amounts from the flour and liquid listed in the recipe. Add the discard starter to the recipe as a replacement.

How much sourdough starter can you substitute? We recommend substituting starter for no more than 1/3 of the flour in the recipe. If you like the result, you can try increasing the percentage the next time. And remember that this process often involves a lot of trial and error; you won’t always get great (or even good) results! But if you’re willing to experiment, try subbing some discard into your recipes and monitoring the results.

Learn more here: Adding sourdough to a recipe, as well as these posts on adding sourdough to cake and adding sourdough discard to dinner rolls.

Glass sourdough crock next to measuring cup full of flour Photography by Kristin Teig; food styling by Liz Neily
A glass crock can be used for both sourdough starter and sourdough discard.

How to store sourdough discard

You can store sourdough discard in a separate container, then bake with it when you want — for instance, maybe you fed your starter on Tuesday, leaving you with discard that you want to use to bake pancakes on Saturday.

To store sourdough discard, keep it in a lidded container — a jar, sourdough crock, or other vessel you’d use to store starter will all work. You can combine many days’ worth of discard in a single jar, adding to it every time you feed your starter until you’re ready to bake with your discard. If you’re planning to use that day, discard starter can be kept out at room temperature. Otherwise, store it in the fridge until you’re ready to use.

One note: Don’t start using your discard until your starter is really up and running. In other words, if you've just started your starter and it's not yet established, then you shouldn't save that discard. Wait until you have a healthy, active sourdough starter, then keep any discard from routine feedings.

How long is sourdough discard good for?

Kept in the fridge, sourdough discard will last several weeks. Similar principles apply to sourdough discard as they do to starter; black liquid on top is totally fine, but streaks of pink or orange mean that it’s likely contaminated and should be tossed.

Just learning to bake with sourdough? Check out our beginner’s guide to sourdough, then dive into our full resource on learning sourdough baking.

Cover photo by Kristin Teig; food styling by Liz Neily.

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About Rossi Anastopoulo

Rossi Anastopoulo grew up in Charleston, South Carolina, which is how she fell in love with biscuits. She didn’t have any bakers in her household (with the exception of her grandmother’s perfect koulourakia), so she learned at a young age that the best way to satisfy her sweet tooth was to make dess...
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