Biga

Biga names a family of stiff yeast preferments — flour, water, and commercial yeast fermented ahead of the dough — not a single sourced hydration number. The allowed sources in this corpus do not publish a biga water percentage. Treat it as the dry neighbor of Poolish, not as poolish with a secret ratio.

King Arthur Baking's baker's-percentage teaching uses poolish as the preferment example: equal flour and water. A stiff preferment will not look like that line. You still recast it the same way: break the preferment into flour and water, add those weights into the dough, and read overall Baker's percentage ¹. The flour that fermented overnight is Prefermented flour.

Calvel's account of preferments is the technical frame for why bakers ferment part of the Wheat flour before the mix: flavor, dough maturity, and a different mix than a straight dough ². He is not a source here for an Italian shop's biga formula.

Biga is not Pâte fermentée. Old dough already carries salt and whatever the previous bread carried. Biga is built as a preferment, typically without that salt load.

What to notice #

A stiff preferment holds a shape; a poolish does not. Ripe, it is aerated and domed, not a dry brick and not collapsed and alcoholic. Incorporating it is a Dough development problem: pieces of stiff sponge have to disappear into the dough without leaving cores. Biga hydration belongs to the bread formula; treat an uncited number cautiously.