Poolish, biga and levain compared

Poolish, biga and levain at a glance

All three move part of a recipe’s flour and water into a separate mix that ferments for hours before the final dough is made. The figures below are typical values from professional formulas, with percentages based on the preferment’s own flour [1][2][3][4][5].

How to build each preferment

Poolish

Mix equal weights of flour and water with a pinch of yeast until smooth, cover and leave at room temperature. Use 0.1 to 0.2% yeast on the poolish flour and ripen it for 8 to 16 hours; a room at 18 °C (65 °F) needs more yeast than one at 24 °C (75 °F) [1]. More yeast makes a faster poolish: with 3% compressed yeast it is ready in 1 to 2 hours [3]. For a home batch, use 300 g flour and 300 g water, then follow a specific poolish recipe for the type and amount of yeast and its fermentation conditions. Instant, active dry and compressed yeast are not interchangeable gram for gram.

Biga

Mix flour with 50 to 60% of its weight in water and about 0.1% instant yeast (or 0.8 to 1.5% fresh) only until no dry flour remains; you are not trying to develop gluten yet. Ferment it for 8 to 16 hours at 15 to 20 °C (59 to 68 °F) [4]. A ciabatta biga typically holds about 30% of the total flour [6]. A home-sized batch: 300 g flour, 180 g water and 0.3 g instant yeast.

Levain

A levain is built from a portion of ripe sourdough starter plus fresh flour and water. A liquid levain is typically 100 parts flour, 100 to 125 parts water and 20 parts ripe starter by weight, left 12 to 16 hours at room temperature [7][8]. A stiff levain uses about 60% water. Temperature shapes the acidity: 29 to 32 °C (84 to 90 °F) favours lactic acid, while lower temperatures favour acetic acid [5]. A home-sized batch: 150 g flour, 150 g water and 30 g ripe starter.

Accounting for a preferment in baker’s percentages

Work from the overall formula. Decide the total flour, water and salt for the whole recipe, choose how much of the flour to preferment, then subtract the preferment’s flour and water from the totals to get the final dough. This is the standard layout for professional bread formulas [9][10].

Prefermented flour (%) = flour in the preferment (g) ÷ total flour (g) × 100

Worked example: 1 kg flour at 70%, 30% prefermented

The overall formula is 1,000 g flour (100%), 700 g water (70%) and 20 g salt (2%). With 30% of the flour in a 100% poolish, the poolish holds 300 g flour and 300 g water. Yeast is left out of this flour-and-water example; use the type and quantity your recipe requires.

• Hydration both ways: the final dough alone is 400 ÷ 700 × 100 = 57%, while the overall formula is 700 ÷ 1,000 × 100 = 70%.
• Preferment as an ingredient: 600 ÷ 700 × 100 = 86% of the final-dough flour. A recipe written on the final-dough convention would list the poolish this way.
• Swap in a 60% biga at the same 30%: the biga holds 300 g flour and 180 g water, so the final dough gets 700 g flour and 520 g water. Final-dough hydration rises to 74%, but the overall hydration is still 70%.
• Yeast: add the final-dough yeast your recipe calls for. Because the preferment is already fermenting, the final dough usually needs a shorter bulk fermentation.

For how to state hydration when a recipe uses a preferment, see dough hydration explained. The baker’s percentage calculator splits a preferment into its flour and water and reports the prefermented flour for you.

Readiness cues

• Poolish: risen, bubbly across the surface and pleasantly tangy. At its peak the surface starts to wrinkle and the volume begins to drop slightly. Left much longer, it breaks down gluten and builds too much acidity and alcohol.
• Biga: domed, and just beginning to recede in the centre.
• Levain: doubled or tripled in volume, foamy, pleasant smelling and just starting to sag in the middle. A fed starter often reaches this point 6 to 8 hours after feeding [11]. Do not rely on the float test: starter can float before it is ripe, although a sample that sinks is definitely not ready [12].

Clock times in recipes assume a temperature. If your kitchen is cooler or warmer than the recipe’s, watch the preferment rather than the timer.

Illustrative texture references, not a timed fermentation experiment. Use the readiness cues with your recipe and kitchen temperature; a photograph or float test alone cannot establish readiness.

Which one should you use?

• Poolish if you want an extensible dough for baguettes or other lean breads and can mix it the evening before. Its batter-like texture blends easily into the final dough.
• Biga if you are making ciabatta or another wet Italian bread and want extra strength and an open crumb, or your kitchen runs cool.
• Levain if you want sourdough flavour, acidity and keeping quality without commercial yeast, and you already keep an active starter.
• No separate preferment for Neapolitan pizza made to AVPN rules, which describe a direct dough and allow natural sourdough at under 10% of the flour [13]. Work out the dough in the pizza dough calculator.

If you cannot decide between poolish and biga, choose by schedule and handling. Once the overall hydration matches, the finished loaves differ very little, and a 100% poolish is easier to mix in evenly than a stiff preferment [14].

Keep your formulas together in CookBook

CookBook saves bread and pizza recipes from websites, social posts, photos and cookbooks, and keeps them organised in one place. In cooking mode you can change servings and switch measurement systems: ingredient amounts scale, but times in the method do not, so keep reading the preferment, not the clock.

Sources

1. King Arthur Baking: Preferment (professional reference)
2. King Arthur Baking: Baking with preferments
3. BAKERpedia: Poolish
4. BAKERpedia: Biga
5. BAKERpedia: Levain
6. King Arthur Baking: Ciabatta (professional formula)
7. King Arthur Baking: Sourdough Baguettes (professional formula)
8. King Arthur Baking: Five Seed Sourdough (professional formula)
9. Bread Bakers Guild of America: Formula layout standards, part I (Bread Lines, 2009)
10. King Arthur Baking: Baker’s percentage (professional reference)
11. King Arthur Baking: Ripe sourdough starter, here’s what that means
12. King Arthur Baking: The float test for yeast dough and sourdough starter
13. Associazione Verace Pizza Napoletana: Disciplinare 2024 (English)
14. Modernist Bread: Are biga, poolish and sponge interchangeable?