Baking with Discard Sourdough Starter

sourdough scones

I feed my sourdough starter twice daily most of the time, which means I end up with a fair amount of “discard” starter. Now, I’m not the most ambitious discard user out there (i.e. I don’t mind composting it), but lately I’ve been trying to incorporate it more often into some of my “normal” (read: non-sourdough) baking. So if you’re looking to up your discard game, here are some ideas to get you started. If you have any favorite discard recipes to share, please leave them in the comments — I’m always interested in more ideas!

Adding Sourdough to Quick Bread Recipes

sourdough banana bread
Replacing some of the flour and liquids in quick bread (including scone and pancake) recipes is one of the easiest ways to use up discard starter. You don’t even need a specific “sourdough” recipe. Since starter is, essentially, flour and water, all you have to do is measure out the amount of starter you want to use and subtract that amount in flour/liquid called for in your recipe.

Say, for example, you have 100g of starter you want to use up, and your recipe calls for 225g of flour and 100g of water. If your starter is 100% hydration (equal parts flour and water), simply subtract 50g of flour and 50g of water (100g total) from your recipe and use starter in its place (I typically whisk it in with the wet ingredients). This is definitely easiest to do if you are baking by weight, which I highly recommend (this OXO digital scale is definitely my most frequently used kitchen appliance).

If your recipe doesn’t call for water you can replace another liquid instead — say milk, juice, or even oil. Just keep in mind that these ingredients contribute more than just hydration to the final product (i.e. sweetness, flavor, fat) so you may not want to replace all of it.

Note: When I use sourdough in these situations it’s purely for “less waste” reasons — not for leavening. I still keep the chemical leaveners (baking soda/powder) in. My starter is refreshed pretty often and is quite mild, so I don’t really detect any “sourdough tang” in the final product (maybe a little in pancakes). But if your starter has been sitting in the fridge for awhile or is especially acidic you might have different results. Finally, you’ll also need to experiment with the amount of starter you can sub in for your individual recipes. For quick bread loaves I usually sub around ~20-25% of the flour weight; higher percentages tend to lend a bit of a “spongy” texture in my experience, but it really varies with the recipe.

Here are a few recipes on CTD in which I’ve successfully used discard starter:

Sourdough Granola

sourdough granola

Making granola one of my current favorite ways to use up discard because it’s so easy and and flexible! This formula/guideline is largely inspired by my Instagram friend Fumi. The starter basically acts as a binder so you end up with a nice crunchy, clumpy granola (my favorite kind!) without having to add too much sweetener or fat.

Preferment:

  • 100g sourdough starter (100% hydration; can be straight from the fridge)
  • 30g water
  • 30g brown sugar (light or dark)
  • 30g flour (AP or whole grain)

Mix and ferment for 3-8 hours. (Fermenting isn’t necessary but I typically let mine ferment for at least 3 hours.)

Final mix:

  • 1/4 tsp kosher salt
  • 160g rolled oats (not instant)
  • 70g raw, unsalted nuts (roughly chopped if large)
  • 50g mixed seeds (flax, sunflower, pumpkin, millet, sesame…)
  • 20g honey or maple syrup
  • 15-30g neutral oil (I like grapeseed)
  • Mix-ins: Dried fruit, cacao nibs, crystallized ginger

Method:

  1. Preheat the oven to 300F.
  2. Combine all the dry ingredients except for the mix-ins in a large bowl. Whisk the wet ingredients (honey/maple syrup and oil) into the preferment, then pour the wet ingredients over the dry and mix to combine.
  3. Spread the mixture thinly on a silicone or parchment-lined baking sheet.
  4. Bake for ~45 min, rotating pan halfway through. If the granola is browning quickly, turn the oven down to 275 or 250 halfway through baking. Turn oven off and allow to cool for ~30 minutes, then break the granola into pieces and return to the turned-off oven to cool completely. Add mix-ins once completely cool and store in an airtight container.

Other recipe ideas

Here are some other recipe/resource ideas for using up sourdough starter discard: