Bubbles in sourdough starter
How Long Sourdough Discard Lasts In The Fridge
Sourdough discard is the bit of bread starter that is removed from the larger starter before feeding, and it has a significantly shorter shelf life than a regular starter.
At room temperature, the discard only lasts a day or two, but it can last up to a week when stored in an airtight container in the fridge.
To make sure the discard hasn’t gone bad, check it for any off smells, like a strong, acidic odor, along with spots of discoloration or visible mold growth.
If you don’t plan on using all of the discard before it goes bad, you can freeze it in individual portions, which will last indefinitely until thawed.