Hey all! First time posting in here, what a cool resource!
So! I have this bagel recipe, and it's fantastic and makes truly gorgeous bagels, but I also have a great sourdough starter and I wanted to use it to make delicious sourdough bagels. Can any one help me figure out what the math would be to substitute starter for the yeast? Do I add it to the poolish? Recipe below, thanks!
Poolish/Sponge:
270 Grams Bread Flour
270 Grams Cold Water
¼ Tsp Yeast
Dough:
Add 275 Grams of water
Add ¾ of a tsp of yeast
Add Bread Flour 655g
Add 6 grams of diastatic malt
Add 17 grams of Salt (add away from yeast
You can just replace poolish with starter. Seeing how starter, poolish, sponge, biga etc. all fall into the same category of yeasted preferments, it should work just as well. Maybe start with mixing 50% poolish and 50% starter, then add the rest and see how that works out.
Very Cool! Ok, I'll give that a shot, do you think I'd still add the additional yeast in the second portion? And for the poolish/starter, just use the same weight amounts?
Now that you said it I guess that makes perfect sense... the poolish is straight up 1:1 flour/water and so is the starter. I shall return with results!
Yes, I would still add yeast in the second portion as starter works slower than yeast. They get along very well.
And yes, just use the same amounts. Based on my experience, for the poolish I would mix 100 g starter, 250 g water and 250 g flour (1:2,5:2,5). That is 600 g, but it will lose a bit of weight and you should end up with enough pre-ferment plus a little extra for continuing. It should be ready to use in about 12-14 h, depending on your room temp.
So do that and then just use it and proceed with the recipe as usual.
Great advice from others. My approach would be a little different. When I convert commercial yeast recipes to sourdough, I usually start with around 15-20% of flour weight in levain to avoid an overly sour product. I then add yeast when putting the final dough together.
Your recipe could look something like this:
Levain (12-16 hr)
160g Flour
160g Water
25g Mature liquid levain
Final
345g Mature levain
373g Water
6g Yeast
753g Flour
6g Malt
17g Salt (I would consider increasing this to 19g so you are at 2% salt)
Let me know if you have questions,
Zuri