Unfed, typically past-peak sourdough starter that's been set aside -- still useful for adding flavor and tang to recipes that don't need leavening power.
Discard starter is more acidic and less active than a freshly fed starter, but it still contains all those fermentation flavors. It's perfect for recipes that use baking powder or baking soda for leavening (like pancakes and muffins) or recipes that don't need to rise at all (like crackers and tortillas). Don't use discard from the first few days of creating a new starter -- those early batches may contain unwanted microorganisms.
