How To Add Sourdough Discard to Any Recipe (Grams & Cups Explained!)

Learn how to add sourdough discard to any recipe. It’s a simple calculation that can transform your favorite recipes into delicious sourdough creations.

This post includes the conversion for grams and cups so you can adapt any recipe, whether you weigh or measure the ingredients.

How To Add Sourdough Discard to Any Recipe

This conversion assumes that you are using a 100% hydration starter, which is just a fancy way of saying that your starter is fed equal parts flour and water.

Here is how you calculate the recipe in grams:

• Weigh the amount of discard you want to add to the recipe.
  • Let’s assume you weigh out 100 g sourdough discard.

• Divide the weight of your starter in half. We do this because your starter is made with half flour and half water.
  • Half of 100 g discard is 50 g flour and 50 g water.

• Check the weight of the flour and liquid in the original recipe.
  • Assume the recipe calls for 400 g flour and 150 g milk.

• Reduce the flour and liquid in the original recipe by half of your starter’s weight (50 g flour and 50 g liquid from Step 2).
  • If the original recipe calls for 400 g flour, convert the recipe to 350 g.
  • If the original recipe calls for 150 g milk, convert the recipe to 100 g.

• Continue the recipe as usual. Mix the discard in with the liquid ingredients.

Cup Measurements Explained

The easiest way to add discard to a recipe is by using weight, not volume. It is a more precise and repeatable way to bake.

If possible, I recommend using a waterproof kitchen scale when making sourdough discard recipes. It makes life much easier.

But you can still add discard to a recipe even if you don’t have a kitchen scale. It’s just not as cut and dry because sourdough is almost always referenced in grams, not cups.

Here’s how you do it:

• Convert from grams to cups. 100 grams of unfed discard is approximately 1/3 cup, which is equivalent to 1/3 cup flour and 2 tablespoons + 2 teaspoons of water.

• Measurements needed – If you are using 1/3 cup of discard, you will need to reduce the flour in the recipe by 1/3 cup and the liquid by 2 tablespoons + 2 teaspoons.

As you can see, the conversion from grams results in odd volume measurements. I usually round the conversion to the closest, even measurement.

Most discard recipes are forgiving, but adjust the recipe as necessary.

Video – Sourdough Discard Explained

Learn the difference between active starter, inactive, and discard. I’m breaking it down into easy-to-understand examples so you can master sourdough!

Don’t forget to subscribe to my YouTube channel for more sourdough recipes and tutorials. New videos come out weekly.

Tips for Success

Pour off the hooch. If any grey liquid is on the surface, pour it off before using your starter. Though it looks funky, hooch is just a sign your starter is hungry.

Don’t use more than 200 g. I usually stick with 50-100 g of discard. But you can use up to 200 g if you have more discard to use.

Watch the acidity. The older the discard, the more acidic and sour it will taste. So, if you prefer less sourdough flavor in your baked goods, use a recently fed starter.

Add discard with the liquid. The starter will combine more easily if you add it with the liquid. Since egg is an emulsifier, I usually toss the discard in with the eggs.

Jot down your conversions. Make a note of the conversions before you start baking so you don’t get mixed up. And save them for next time!

What If the Recipe Doesn’t Call for Liquid?

Some recipes, like einkorn chocolate chip cookies or sweet breads, don’t call for any liquid, so adding discard can be tricky.

Luckily, it’s still possible with these easy tips:

Use a small amount of discard. Use around 50 g of discard. A small amount like that doesn’t have major effects on a recipe.

Reduce the flour slightly. If you add around 50 g of discard, reduce the flour in the recipe by about 15-25 grams or 1-2 tablespoons. This is slightly different from the suggested conversion, but since there isn’t much liquid to reduce, you don’t want to remove too much flour.

Reduce a touch of liquid if possible. Use a smaller egg if you have one. But as long as you don’t add too much starter, the difference in liquid is mostly negligible.

Recipe Examples

Seeing is believing! Here is how this conversion works in a few example recipes.

Note: I rounded to the nearest, even measurement for the volume examples.

Vanilla Cake Recipe

• 240 g all-purpose flour (2 cups) >>> 190 g all-purpose flour (1 ^1/2 cups)
• 100 g sourdough discard (1/2 cup)
• 2 tsp baking powder
• 5 g salt
• 333g sugar
• 170g butter
• 3 eggs
• 13 g vanilla extract
• 227 g buttermilk (1 cup) >>> 180 g buttermilk (3/4 cup)

Chocolate Chip Cookie Recipe

Recipes without liquid can be tricky to convert. Be sure to check out the section above that explains how to add starter to recipes without liquid.

• 227 g butter (1 cup)
• 232 g sugar (1 cup)
• 213 g dark brown sugar (1 cup)
• 13 g vanilla extract (1 tbsp)
• 2 eggs
• 360 g all-purpose flour (3 cups) >>> 344 g all-purpose flour (or reduce by 2 tbsp)
• 50 g sourdough discard (approx. 1/4 cup)
• 6 g baking soda (1 tsp)
• 3 g  baking powder (1/2 tsp)
• 6 g salt (1 tsp)
• 396 g dark chocolate chips (2 cups)