leavening dough without commercial yeast

[elizabee]

Howdy folks,

I am wondering whether a new batch of dough could be leavened by reserving a small piece of dough from an old batch rather than buying and using yeast all the time. I do something similar with yogurt now and it works fine. Anybody have an experience with this? I usually make a large batch of dough, like enough to make 3-4 loaves (I'm an Artisan Bread in 5 devotee - http://www.artisanbreadinfive.com/), so I wonder, wouldn't that cut the cost? How much dough should I use?

[Mhoram]

That's pretty much how sourdough works.  Once you've got a starter going, you just save back a portion of it every time you bake, and feed it more bread and water now and then to keep it alive.  It doesn't require any yeast, though -- it picks up natural yeasts and bacteria that are floating around in the air -- so I don't know if you can do the same thing with a mixture that involves baker's yeast.