The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Substituting Active Dry Yeast with Sourdough "Sponge"

AurorasBreads's picture

Substituting Active Dry Yeast with Sourdough "Sponge"

Well, here goes nothing! I have been baking for years (the usual...cookies, fruit breads, desserts, etc.) and recently decided to try my hand at bread baking. I baked a few using active dry yeasts from the grocery store and they turned out pretty nice. But I realized that I wanted to make my own starter so I took on an ambitious project of starting one of my own to capture the wild yeasts instead of using the packaged kind. My starter is going well (it's been about 7days) and I am ready to bake my first loaf of bread. My problem, however, is that I can't seem to find any recipes in my books that ask for a sourdough sponge...all they use is active dry yeasts and quick-rise yeasts. I have "Bread Alone" by Daniel Leader and "The Bread Bible" by Beth Hensperger (both great books!) but neither of them seem to have any recipes that call for a sourdough starter that I have made myself. Can you substitute the dry yeasts with the wet ones (the sourdough starter that I have made) and if so, what is the ratio? Any help that could be offered would be greatly appreciated! Thank you and happy baking :)


suave's picture

Have you looked carefully? Second half of Bread Alone has quite a few of sourdough breads.

lief's picture

You can absolutely convert just about any yeast recipe to one that uses sourdough only, keeping in mind that the timetable of the converted recipe is going to be longer than that of the original yeasted recipe and the final results will likely be different (but usually better!).  Check here for a take on different conversion techniques:

That website has lots of other information on sourdough as well.

The basic idea is very simple though: the water and flour in your sourdough sponge displace some amount of water and flour in the recipe such that the total amount of water and flour in your final dough -- after the addition of the sourdough sponge to the dough -- are the same as the original recipe.  Then the only question becomes how much flour and water do you allocate to the sponge versus the final dough.  That depends on how quickly you want the dough to rise.  I've seen anywhere from 15% to 50%, with the usual amount being more in the 25-35% range.  In general, the less sponge you add to the final dough, the longer the timetables are for the recipe and the more sour the final bread is.  Hope this helps!

Aussie Pete's picture
Aussie Pete


Hi Janette.

Just remember when using your sourdough starter to give it a lot more time to do it's job than instant yeast and proof in a warm place in the home...........sorry I am not sure of exchange rations for the yeast and starter.

Good luck..................Pete.

bpezzell's picture

Most of the recipes in Leader's book are sourdough-based. Are you meaning the specific kind of starter you have made?

That book is loaded with delightful formulas, but the math throughout is screwy beyond belief. I'd google each one before attempting.

amauer's picture

It seems that most recipes that call for active dry use a packet which is 2 and 1/4 tsp or 1/4 of an ounce (.25oz)  or 7 grams. Most starter recipes call for about 9 oz starter.

amauer's picture

When I do not have the time to let my sourdough sit as long as it needs, I cheat and use about 1 tsp and 1/2 of active dry yeast with the recipe. It won't change the flavor of the sourdough and it simply rises faster. Andrea