what is the different between a biga, sponge, poolish & preferment?
when you do a no-knead bread, aren't you just sort of baking a giant biga?
Welcome to TFL!
"Pre-ferments" are portions of the flour and water of a dough that are mixed ahead of time and allowed to ferment before adding the remainder of the dough's ingredients for mixing. Their main purpose is to improve flavor and shelf life of the product.
There are several kinds of preferments, differing in whether they contain yeast, salt or both and in how liquid or firm they are. Each has its own name in the language of its country of origin. Bigas, sponges, poolishes, as well as pâtes fermentées are the most common types of pre-ferments.
A biga is a relatively solid (low hydration) mixture of flour, water and a small amount of yeast used in Italian baking.
A poolish is a relatively liquid mixture of flour, water (50-50%, by weight) and a small amount of yeast used in French baking.
My understanding is that a sponge is like a poolish but with a higher proportion of yeast. It is used after a much shorter time after it is mixed than a poolish would be.
A pâte fermentée is a mixture of water, flour, yeast and salt. It is classically a piece of dough saved from the last batch made. It can be made special though. It is characterized by having the same ingredients in the same proportions as the final dough.
In regard to your question about no-knead bread: It is not like baking a biga, because a biga has no salt. It is like baking a pâte fermentée.
I hope this answers your questions.
Thanks dmsnyder, very clearly stated. I'd give it 5 stars if I could figure out how to get it to register.