Experienced Baker Guide
Leaven Instant Sourdough can be used in a variety of ways, just like instant yeast, preferments, and starters can.
We still recommend trying our recipes first (we put lots of work into them!), but if you want to adapt your own formula to use with Leaven, this guide should cover it. If you need more help, you can also contact our trusted in-house bakers at info@leavenfoods.com for assistance.
The Substitution Method
For Instant Dry Yeast
Replace the instant dry yeast in your formula by multiplying the given amount by 6.5 and adding in the corresponding quantity of Leaven Instant Sourdough. Then just follow the formula as written. That’s it!
Important note:
Some formulas call for high amounts of instant yeast. The Substitution Method should not be used in formulas that call for more than 0.2% instant dry yeast by baker’s percentage. If your recipe calls for more than that, it’s better to try one of our custom recipes or use The Preferment Method below.
For Sourdough Starter or Preferments:
The activity level of sourdough starters obviously varies, but this substitution should get you close. For every 5% of sourdough starter or preferment in a formula, replace it with 0.65% by baker’s percentage of Leaven All Purpose or Wild Yeast. Seems pretty easy, right? Well, as you probably know, there are multiple ways to calculate the percentage of preferment in a formula; We calculate it by measuring how much of the formula’s total flour comes from the preferment, also known as prefermented flour percentage.
Example:
Imagine a formula calls for 10% prefermented flour out of a total of 1000 grams of flour. A typical starter is at 100% hydration, meaning equal parts flour and water by weight. To use 10% prefermented flour in this formula, add 900 grams of fresh flour and 200 grams of preferment (because it’s only half flour), along with the remaining ingredients.
Prefer math? 100 grams flour in starter ÷ 1000 grams total flour = 0.1 or 10% prefermented flour.
Important note:
As with instant dry yeast, The Substitution Method can’t be used in formulas that use greater than 10% preferment. It’s better to try one of our custom recipes. Also, trust us, more than 10% preferment is too much!
The Preferment Method
Ask any pro and they’ll tell you: preferments produce superior flavor and texture compared to mixing all ingredients at once. The Preferment Method is great for formulas that call for a poolish or biga, as well as those with large quantities of instant dry yeast that The Substitution Method can’t handle.
How to Make a Preferment:
Time, temperature, and quantity of Instant Sourdough depend on whether your formula calls for a poolish or a biga, so begin by identifying your desired schedule in the baker’s tables below. Next, combine flour and water with Leaven Instant Sourdough to form a preferment. Finally, allow the preferment to develop at the proper temperature.
The baker’s tables reflect when preferments reach their peak activity, but you have an hour of flexibility on either side of each listed time.
Poolish (100% Hydration)
| Temperature | Time | Leaven All Purpose or Wild Yeast % |
|---|---|---|
| 60 F | 18 hours | 1.6 |
| 60 F | 24 hours | 0.85 |
| 72 F | 4 hours | 2.92 |
| 72 F | 6 hours | 1.95 |
| 72 F | 8 hours | 1.6 |
| 72 F | 16 hours | 0.33 |
| 80 F | 4 hours | 1.6 |
| 80 F | 8 hours | 0.65 |
| 80 F | 12 hours | 0.33 |
| 80 F | 16 hours | 0.16 |
Biga (50% Hydration)
| Temperature | Time | Leaven All Purpose or Wild Yeast % |
|---|---|---|
| 72 F | 6 hours | 2.925 |
| 72 F | 12 hours | 1.6 |
| 72 F | 16 hours | 0.6 |
| 80 F | 6 hours | 1.6 |
| 80 F | 8 hours | 0.6 |
| 80 F | 12 hours | 0.33 |
Preferment Inclusion Guide:
Poolish (100% Hydration)
| Instant Dry Yeast (Baker’s %) | Instant Dry Yeast Poolish or Sourdough Starter (Prefermented Flour %) | Leaven Poolish Inclusion (Prefermented Flour %) |
|---|---|---|
| 0.1 | 5.0 | 10.0 |
| 0.2 | 10.0 | 15.0 |
| 0.3 | 15.0 | 25.0 |
| 0.4 | 20.0 | 30.0 |
| 0.5 | 25.0 | 35.0 |
| 0.6 | 30.0 | 40.0 |
| 0.7 | 35.0 | 45.0 |
| 0.8 | 40.0 | 50.0 |
| 0.9 | 45.0 | 55.0 |
| 1.0 | 50.0 | 60.0 |
Biga (50% Hydration)
| Instant Dry Yeast (Baker’s %) | Instant Dry Yeast Biga or Stiff Sourdough Starter (Prefermented Flour %) | Leaven Biga Inclusion (Prefermented Flour %) |
|---|---|---|
| 0.1 | 5.0 | 10.0 |
| 0.2 | 10.0 | 15.0 |
| 0.3 | 15.0 | 25.0 |
| 0.4 | 20.0 | 30.0 |
| 0.5 | 25.0 | 35.0 |
| 0.6 | 30.0 | 40.0 |
| 0.7 | 35.0 | 45.0 |
| 0.8 | 40.0 | 50.0 |
| 0.9 | 45.0 | 55.0 |
| 1.0 | 50.0 | 60.0 |
Traditional Starter Method
Already comfortable baking with a starter? You can use Leaven All Purpose to create a traditional sourdough starter in as little as 4 hours.
How to Make a Starter:
Using The Preferment Method above, mix Leaven All Purpose (Wild Yeast won’t work for this one) to make a poolish. Once it’s ready, you can use the same percentage your formula calls for, no adaptation necessary. You now have the option to feed the starter and keep it alive like you would a traditional starter.
Try some of our favorite recipes!
Share your bakes with #leavenfoods, tag us @leavenfoods on social media, or drop us a note about your experience.
Happy baking from the Leaven Foods team!
Questions? We’re happy to help! Reach us at info@leavenfoods.com