Timing

The function of a pre-ferment, or dough starter, is to add flavor, texture, and shelf life to bread. A pre-ferment consists of flour, water, yeast, and sometimes salt, in varying proportions. A small amount is mixed before the rest of the dough to start the fermentation process. A biga, an Italian pre-ferment, is close to the consistency of bread dough (from 50 to 78.7 percent water, or hydration). It is usually mixed at least 6 to 24 hours ahead and used within 3 days. Because of its stiff consistency, it is the strongest (in terms of gluten) of the pre-ferments and is particularly useful for strengthening the network of gluten in breads with a high water content. (Biga is the Italian word for a two-wheel chariot. It seems reasonable that it should be used to describe this pre-ferment for bread baking because it is a vehicle that adds great impact in terms of flavor and strength to bread dough.)