When you try new sourdough recipes, you might run into a variety of different preferments. Here’s how to the tell the difference between levain, biga, poolish, and pâte fermentée.

Levain

Levain, AKA sourdough starter, is a basic mix of flour and water. It does not use commercial yeast. Rather, it focuses on developing natural yeasts and bacteria already occurring in the flour and the air.

Levain takes several days of active feeding before it’s ready for use in baking. Although you can make a levain in about 5 days, the longer you maintain the levain, the more flavorful and fluffy your bread will be.

Stiff Levain vs. Liquid Levain

Many sourdough recipes use levain, but the consistency of that levain varies widely.

As a general rule, if a recipe calls for a stiff levain, then it needs a starter with 60% hydration or below.  A liquid levain, in contrast, typically uses 65% hydration or higher. If you wanted to make a liquid starter, you could combine 2 parts flour to 1 part water (or close to it).

Poolish

Poolish is similar to liquid levain in that it ferments at 100% hydration, or equal parts water and flour. However, unlike liquid levain, poolish only ferments for a few hours (anywhere from 12 to 16 hours) rather than a few days.

It uses a small percentage of commercial yeast to do the work, about 0.1-0.2% fresh yeast.

Biga

Biga is similar to stiff levain in that it ferments at 50-60% hydration, or 2 parts flour to 1 part water, or 100 grams flour to 50-60 grams water. Additionally, biga is similar to poolish in that it relies on commercial yeast to do the work.

Pâte Fermentée?

Pâte Fermentée translates from French to “fermented dough.” It is a handy way to ferment dough from bread you make on a regular basis.

When you make bread, you can set aside 1/3 of your loaf after it has finished its bulk fermentation. You then incorporate the old dough as leaven for your next batch of bread, set aside 1/3 of that loaf after it has finished, and continue the process.