Sourdough Discard Ratio Calculator

How to Use This Tool

Follow these simple steps to get accurate sourdough discard ratio adjustments:

1. Enter the total amount of sourdough discard you have available, and select the unit of measurement (grams, cups, or ounces).
2. Enter the amount of discard your chosen recipe calls for, using the same unit as your available discard.
3. Select the type of recipe you are making from the dropdown menu to apply correct ingredient ratios.
4. Enter the original yield (number of servings) the recipe is designed to produce.
5. Click the Calculate button to see your adjusted ingredient amounts and scaling factor.
6. Use the Reset button to clear all inputs and start a new calculation.

Formula and Logic

This calculator uses a simple scaling method to adjust sourdough discard recipes based on your available discard:

• Scaling Factor = (Your Available Discard) / (Recipe Required Discard)
• All ingredient amounts are multiplied by this scaling factor to match your discard supply.
• Pre-set ingredient ratios for each recipe type account for standard flour, water, and salt proportions relative to discard amounts.

For example: If you have 200g of discard and a pancake recipe calls for 150g, your scaling factor is 1.33. All ingredients will be increased by 33% to use all your discard.

Practical Notes

These real-world tips help you get the most out of your sourdough discard:

• Weight measurements (grams) are far more accurate than volume (cups) for sourdough discard, as density can vary based on hydration and fermentation time.
• 1 cup of sourdough discard typically weighs ~240 grams, and 1 ounce is ~28.35 grams if you need to convert units.
• Discard that is more than 1 week old may have a stronger sour flavor, which works well for crackers or pizza crust but may overpower pancakes or muffins.
• If scaling a recipe by more than 2x, check that your mixing bowl and baking pan sizes can accommodate the larger batch.
• Adjust baking time by 5-10% for larger batches, as thicker layers of batter or dough may take longer to cook through.

Why This Tool Is Useful

Home bakers often end up with varying amounts of sourdough discard and struggle to adjust recipes on the fly:

• Avoid wasting discard by scaling recipes to use exactly what you have on hand.
• Save time guessing ingredient adjustments, with pre-set ratios for common discard recipes.
• Reduce food waste by using all your discard instead of throwing it away.
• Consistently produce well-balanced baked goods, as the calculator maintains proper ingredient proportions.

Frequently Asked Questions

Can I use this calculator for active sourdough starter instead of discard?

This tool is calibrated for sourdough discard, which has lower gluten structure and different hydration than active starter. For active starter, reduce the water amount by 10-15% to account for higher hydration.

What if my discard is a different hydration level than the recipe assumes?

Most discard recipes assume 100% hydration (equal parts flour and water by weight). If your discard is more runny, reduce the adjusted water amount by 5-10%. If it is thicker, increase water by 5-10%.

Can I scale a recipe down if I have less discard than the recipe calls for?

Yes, the calculator works for both scaling up and down. Enter your available discard (even if it is less than the recipe requires) and the tool will adjust all ingredients to match your smaller supply.

Additional Guidance

For best results when using this calculator:

• Stir your discard well before measuring, as liquid and solids can separate during storage.
• If substituting cup measurements for grams, spoon the discard into the measuring cup instead of scooping to avoid packing it down, which leads to over-measurement.
• Store unused discard in an airtight container in the fridge for up to 2 weeks, or freeze for up to 3 months for later use.
• Test small adjustments first if you are unfamiliar with a recipe, to avoid wasting ingredients on a failed batch.