Starter Hydration Conversions
How to convert a 100% starter to a 166% starter
Most of the formulas in my books, “Discovering Sourdough,” are based off one cup of 166% sourdough starter which equals 9 ounces/254 grams of starter (at 166%).
Convert your 100% hydration starter to 166% easily by:
Combine 191 grams of starter at 100%hydration and 63 grams of water, you will have approximately 1 cup/ 9oz of starter at 166%.
191 grams (100% starter) plus 63 grams of water = 1 cup/ 9 ounces/254 grams (of starter at 166% hydration).
How to convert a 60% motherdough to a 100% starter
I’ve had students with a 60% motherdough try to use their motherdough (active hopefully) instead of a 100% starter or change it to a 100% starter (of course you can just start feeding it equal weights of water and flour).
So here is an idea of how to substitute the 60% starter in a formula that calls for a 100% starter:
A 100% starter has (for instance) 100 grams of water and 100 grams of flour. A 60% starter has (for instance) 60 grams of water and 100 grams of flour. So a 60% starter has less water.
If you want to substitute a 60% starter in a formula that calls for a 100% starter you would need to add (for instance): 80 grams of 60% starter and 20 grams of water.
80 grams (60%) + 20 (water)= 100 grams starter at 100% hydration
40 grams of 60% +10 grams of water = 50 grams 100% starter
20 grams of 60% + 5 grams of water = 25 grams 100% starter
If you want to change it over to a 100% altogether, just use one of the above and begin to feed it the same weight of water and flour.
So if you need 200 grams of 100% starter you would add how much 60% motherdough and how much water? (Can you figure out the answer?) Psst see below.
Answer: See where I wrote: 80 grams (60%) + 20 (water)= 100 grams starter at 100% hydration? Just double it.
160 grams of 60% motherdough and 40 grams of water = 200 grams of 100% starter.
You can also use a hydration calculator, there are many available online.
Happy Baking! Teresa