Transform & Preserve

Poolish Preferment

A wet flour-water-yeast preferment that builds flavor and strength before mixing.

Poolish is a loose preferment of roughly equal flour and water with a pinch of yeast, fermented for several hours or overnight before being added to the final dough. It develops acidity, aroma, and extensibility, giving bread a more complex flavor and open crumb. It is a French baking staple distinct from the stiffer biga.

A poolish is a wet preferment built from equal weights of flour and water, plus a small dose of commercial yeast, that ferments 12 to 16 hours before being folded into the final dough. At 100% hydration it has the consistency of thick pancake batter — loose, pourable, and far wetter than the dough it will eventually join — and that wetness is exactly what makes it powerful. The flour's enzymes have free access to starch and protein, generating sugars for browning and breaking gluten into a more extensible network before the dough is ever mixed.

The technique arrived in France in the 1930s via Raymond Calvel, who encountered it while consulting in Vienna and saw it as a way to compensate for weak North American wheat. It is now the workhorse preferment of classic French bread: baguettes, pain de campagne, and country loaves that demand an open crumb, a glossy crust, and the kind of nutty, slightly tangy aroma a straight dough cannot reach.

In practical terms the poolish does three jobs at once. It seeds the final dough with a vigorous, well-fed yeast population, generates organic acids and esters that translate into flavor and a longer shelf life, and its enzymatic carryover makes the final dough more extensible, so even a lean formula can be stretched and developed into an open, well-aerated crumb.

Difficulty: Medium

Types & varieties

Classic poolish

100% hydration bread-flour preferment, 0.1–0.2% yeast, fermented 12–16 hours at room temperature

High-extraction poolish

Built with whole wheat, rye, or other specialty flour for a nuttier, more complex flavor

Same-day poolish

Higher yeast dose (0.5–1%) fermented 3–6 hours for bakers who start in the morning

Cold poolish

Mixed with normal yeast and fermented 24–72 hours in the refrigerator for a more acidic, aromatic profile

How to do it

1
Weigh the ingredients
Measure equal weights of bread flour and cool water (around 20°C / 68°F). For an overnight ferment add 0.1–0.2% instant yeast relative to the flour weight — a typical 200 g batch needs about 0.2–0.4 g, just a small pinch. Use a scale; volume measurements will throw off the 1:1 ratio.
2
Mix until smooth
Whisk the yeast into the water first, then stir in the flour. Beat or whisk briskly for 2–3 minutes, until the batter is completely homogeneous, lump-free, and slightly elastic. Even at this early stage the gluten begins to organize, and a well-stirred poolish will give a noticeably stronger final dough.
3
Cover and ferment
Transfer to a straight-sided, clear container (a quart jar or deli tub works well) and mark the starting level with a rubber band or piece of tape so you can see how far it has risen. Cover loosely — a lid set on top rather than sealed — and leave at 18–22°C / 65–72°F for 12–16 hours.
4
Watch for peak
The poolish is ready when it has roughly doubled to tripled in volume, the surface is domed, and bubbles are visible through the sides of the container, with the center just beginning to sink. The aroma is mildly tangy and yeasty, never sharp or harshly alcoholic. Underfermented poolish is dense, barely risen, and tastes flat; overfermented poolish goes slack, collapses fully, and smells boozy.
5
Use or chill
Fold the poolish directly into the final dough at peak, accounting for its flour and water in the overall formula. If timing slips, refrigerate it for up to 48 hours to slow fermentation, then bring back to room temperature (about an hour on the counter) before mixing so it incorporates evenly rather than shocking the final dough with cold liquid.

Poolish in the preferment family

Poolish sits between two other classic preferments, and knowing the differences makes it easier to pick the right tool for a given dough.

Biga is the Italian equivalent, but at 50–60% hydration it is a stiff, kneadable dough rather than a batter; it produces a more open, chewy crumb and a milder flavor than poolish.
Sourdough levain is also fully hydrated but is driven by wild yeasts and bacteria captured from flour, fruit, or a starter; it is more variable and slower, but delivers the deepest, most acidic flavor of the three.
Poolish is the most predictable of the three because it uses a measured dose of commercial yeast, which is why it is the standard building block for French lean breads and the easiest entry point for bakers new to preferments.

Common uses

Baguettes and other classic French lean breadsPain de campagne and other country loaves that need an open crumb and deeper flavorCiabatta and Italian-style hearth breads that benefit from a wet, extensible doughFocaccia, where the poolish drives both flavor and the glossy, well-blistered crustBrioche and other enriched doughs, with the poolish held to 20–30% of flour weight to preserve strength under butter and sugarPan loaves and sandwich bread, where the acids from the poolish noticeably extend shelf lifePizza dough, which gains extensibility for stretching and better oven spring from a stronger gluten networkAny lean dough where you want more aroma and an airier interior without moving to a full sourdough

Tips & pitfalls

Weigh, don't measure. The 1:1 flour-to-water ratio only works by weight; cup measurements of flour can vary by 20% or more and will leave you with a stiff or soupy poolish.
Use a clear container with straight sides. Watching the rise is the most reliable way to judge readiness, and you cannot do that through an opaque bowl.
Aim for true room temperature, not a warm kitchen in summer. Above 24°C / 75°F the poolish will overferment and turn alcoholic; below 18°C / 65°F it will underferment and taste flat. Adjust water temperature to compensate — cooler water in a hot kitchen, warmer in a cool one.
Hold enriched doughs back from the poolish. Sugar and butter slow yeast, so add them only when you mix the final dough, even though the poolish is part of the same formula.
Don't wait for a full collapse. Poolish is at its best the moment the dome starts to dip in the center; once it falls and the bubbles on the side deflate, flavor and strength both drop off.
Refrigerate to buy time, not to extend quality. A cold poolish still works well for 24–48 hours, but past that the acidity climbs and it begins to fight the final dough rather than help it.
Stir at the start, not at the end. Two or three minutes of vigorous mixing hydrates the flour fully and begins to align the gluten; a barely stirred poolish will perform like a weaker, lumpier version of the same ferment.

Good to know

Origin: Named for Polish bakers; brought into modern French practice in the 1930s by Raymond Calvel
Hydration: 100% — equal weight of water and flour
Yeast (overnight): 0.1–0.2% of flour weight
Yeast (same-day, 3–6 hr): 0.5–1% of flour weight
Fermentation temperature: 18–22°C / 65–72°F
Fermentation time: 12–16 hours overnight, or 3–6 hours with more yeast
Dough proportion: Typically 20–40% of the final dough's flour weight
Storage: Use at peak, or refrigerate up to 48 hours to slow fermentation