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Hi I’m not new to baking bread but have never tried a sourdough. I never really knew what it was but vaguely remember my Mum trading starter with friends in the 70’s. Today as grocery store is completely sold out of yeast in corona lockdown I’ve gone down the rabbit hole researching a substitute. Now I’m excited to try making a starter. My question is can this starter be used as a substitute for commercial active dry yeast in recipes that call for it? If so, how would I do that? Is there a special ratio are there pitfalls I should try to avoid? I’d really appreciate any help or advice you could give. I hope this is the right place to post.
Short answer is YES! Starter can be used as a substitute for commercial yeast.
How … so, starter is typically equal weight flour to water referred to as 100% hydration starter.
When I convert a commercial yeast recipe to a sourdough/ Naturally leavened recipe, I sub 62-100 grams starter for 2 1/2 tsp yeast. But really, starter amount can be small. What will need to be adjusted is bulk fermentation time. It will be longer with starter.
If you have a recipe you are familiar with, start there and sub starter … ultimately going for the look and feel of the dough that you know is right … but might be longer to get there
I started from “traditional” baking … then “artisan in 5” and then sourdough. I know you probably want/need bread now so … if you get a starter going, to use it is not a big deal. BUT to get your feet wet, try your starter in the basic no knead recipe here and build on that experience.
@redone, more info and some links … I wrote the above last night when I was too tired 
So, there is a recent recipe: on Food52 based on a KAF recipe … for a kind of deep dish pizza.
I converted the yeast recipe to sourdough:
Original
240 g AP Flour
3/4 tsp salt
1/2 tsp yeast
170 g warm water
1 T olive oil + 1.5 T olive oil for pan
Sourdough
80 g starter (so that is 40 g water, 40 g flour in the starter which I back out of the recipe quantity
200 g flour
130 g warm water
3/4 tsp salt
1 T olive oil + 1.5 T olive oil for pan
The method calls for some folds and then into the frig for a 12-72 hour cold rise (very flexible time :))
I knew my starter would be fine for those time frames. I warmed, shaped and then baked per the recipe at about 24 hours after refrigeration.
That is actually 1/2 the recipe in a 5 1/4 inch cast iron mini-skillet.
I posted a Sourdough Brioche recipe that I converted similarly.
And finally, a great article on sourdough in general: Demystifying Sourdough Bread Baking. I think this article by @homebreadbaker (Paul) should be required reading for all sourdough bakers :).
Hello. I hope you are all keeping safe and well. I can no longer find either bread flour or all purpose four, but I did find two bags of whole wheat flour. I do not however, know how to bake with only whole wheat flour. Could you help? Extra credit for a recipe for only whole wheat flour no-knead bread… Thank you!! And again, keep safe and well.
I cannot help you with an exact recipe … but here is what I would do if I had only whole wheat flour:
If I had Vital Wheat Gluten, I would add 30 g VWG for every 300 g of whole wheat flour in something like the No knead sourdough recipe on this site.
Next option is watery mashed potatoes. I am not kidding. In the time of WW1 and WW2 when it was Whole Wheat or nothing … mashed potatoes and/or watery mashed potatoes were added to soften/fluff up the crumb of 100% whole wheat.
If I were in your spot, I would search for “whole wheat potato bread” and see what comes up for recipe/ratio.
You could try sifting out the bran, or some of it. It depends on the mesh size of your sifter. It won’t be just like white flour, but it would likely lighten up your bread a little. And what some do then is before baking, sprinkle the bran on top of the dough.
Thank you, Liz and Arlo! I’ll try it both ways and post about the outcome.
Substitute any amount but remember that starter is flour and water and adjust so the total of each remains the same. Now depending on how much starter you have used will effect on how long the dough needs to ferment. There’s no one rule for how much… that is left to your own discretion.
Thank you, Abe.
In my hometown, there is plenty of AP flour but no bread flour. I have been able to procure 50 lbs of high gluten four (which is 13.5% protein). I usually use King Arthur Bread flour which is 12.7%. I am trying to find out what I will need to do differently with a higher gluten content. Most of what I read is about how to deal with a lower level and hence concentrate on strategies to increase strength. What do I do with too much? Add a little AP in? I want to continue making a variety of sourdough breads, not bagels! What can you suggest for adjustments?
You’ll only make bagels out of that if you boil the dough otherwise enjoy some of the pros that comes with the higher gluten percentage.
As a rule the higher the percentage the better it is for bread. Might make it more chewy but some people actually prefer that. You can always add some other flour be it AP or wholegrain or rye etc. You can also bake it in a pan for a softer sandwich loaf. Here is a soft loaf baked in a pullman using 14% protein khorasan flour.
Should I adjust anything? Or just sub 1 for 1 high gluten (13.5%) for the 12.7%? More/less water? I always use other flours in combination in all my breads (a little rye, whole wheat and sometimes type 85 when I have it).
That’ll work. Just edited my post above. You can add up to 20% rye or whole wheat which will alter the crumb a bit. If you stick with all strong bread flour then lowering the hydration will have an effect. How high is it now?
Right now I use a flour that’s 12.7%. The new flour that’s coming is going to be 13.5%
How high is the hydration for an all white sourdough you usually do?
I never do all white sourdough. Maximum white is usually 75% and hydration is usually 80% (if you parse the starter into flour and water amounts)
Drop it down to 65 - 70%. Start off at 65 and if too low you can add water till 70%. Should help with a closer more softer crumb. You can also add some oil, about one tablespoon, for a softer crumb.
But I really don’t think its such a great jump that you’ll notice a big difference.
Good to know. Thanks for your thoughts (and expertise)! My bread is already quite chewy (which I love) but was worrying (perhaps too much?) about how this change would effect my baking.
If you dont mind a little chewy and you already never do more than 75% white flour then I wouldn’t change a thing. It’ll be fine!
