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Save Your Sourdough Starter Leftovers

This flavorful leftover culture can be used as backup—or to add tang in all sorts of applications.

The daily or twice-daily process of refreshing sourdough starter generates a leftover portion that you should save as backup in case something happens to the current batch. Eventually, you can also collect generations of backup starter and put them to work in other, nonbread applications.

Backup:  The first time you refresh your nascent starter, keep the remainder as backup in the original jar in the fridge. When you refresh your starter again the next day, throw away the backup (when you're refreshing the starter just once daily, as in Step 2, the backup is not mature enough to use in other applications, so you should dispose of it), clean out the jar thoroughly, use that jar to store the day's newly refreshed culture, and refrigerate the rest as the new backup.

Backup for Cooking (“Sourdough Discard”): Once you reach Step 3 and are refreshing the culture twice daily, you can collect generations of backup (some sources refer to leftover starter as “sourdough discard”) in a single sealed jar—you'll need a third, larger one—and refrigerate them for up to two weeks. Once you have amassed a cup or two of this sourdough discard, you can use it to flavor all sorts of doughs and batters by replacing a portion of the flour and/or liquid with this flavorful culture. Try it in drop biscuits, pancakes, and crackers. (Note that this sourdough discard cannot be used in place of a leavener.)

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