For most breads, is there any reason one can't just use sourdough starter instead of yeast, and subtract the amount of flour and water in the starter from the overall amount in the formula?
I haven't tried going from yeast to starter but vice versa, I used yeast instead of a sourdough starter in a SD recipe.
when i first started making a starter and it wasn't ready to be used, i substituted the 50 g of starter with half a tsp of yeast. i didn't adjust the flour or water in the recipe. I chose to use a tiny bit of yeast so i could mimic the fermentation time . I was dying to make sd bread so i thought i could practice this way. The bread turned out so fantastic that i was willing to settle for just making it with yeast and give up on the starter. so maybe you can use 50g of starter for every half teaspoon of yeast that the recipe calls for. if you don't mind the change in the dough's hydration, you won't have to subtract the flour and water. come to think of it, if say the yeast recipe asks for 2 tsp of yeast that would be 200g of starter and with 100% hydration that's 100g of flour and 100g of water which might be a significant change in hydration. so you may want to subtract that from your recipe. i subtracted 50 g of starter and replaced it with yeast, which is only 25 g each of water and flour and didn't feel it was a big enough diff to replace that in the recipe. sorry i hope i make sense
The crumb and texture of your bread may change. my fake sourdough bread was more light and airy than one made with starter.
One just has to apply sourdough handling techniques to the dough after the dough is mixed up. That is; folding and such should the dough need it and not letting the final proof rise to double the original mixed volume for more oven spring. The timing and flavours will be different so prepare yourself for those changes. Some flours are better than others for feeding the levain (starter) and require some switching around in the order they are incorporated. Watch your amount of prefermented dough, the more you use the shorter the bulk rise and final proof.
For a beginner, there is more security in using a "tried & true" sourdough recipe as opposed to an experiment but if you're adventurous, go ahead. Just be sure to mention when reposting a trouble shoot, what was done, the timings and what you hoped to achieve. :D
I just experimented with going from dry yeast to levain/starter. I found a calculation here but now that I reviewed it, I didn't do it correctly. However, the brioche rolls turned out pretty good - it definitely needed more levain though, which I plan on increasing the next time.
The calculation is:
(All flour + water/hydration) / 6 = levain quantity
Then subtract the levain out of the original flour and water/milk. Example:
Levain needed: (500+200)/6 = 117grams of 100% hydration starter
500g - 117/2 = 440.5g
200g - 117/2 = 140.5g
Let me know how yours turns out! I'll try mine again in a few days. J
You will have longer proofing times. Really need to base things on the dough and not the times in the recipe.
Thanks everyone for your feedback. I bake almost exclusively SD, but thought it might be interesting to see how challah turns out using starter instead of yeast. At one time I suppose most breads were SD. I'll let you know how it turns out.
Santa Cruz CA