Levain vs Starter: What's the Difference

Sourdough recipes use two words that often get mixed up. A starter is the ongoing culture of wild yeast and bacteria that you feed and keep in a jar for months or years. A levain, sometimes called a leaven, is a separate mixture made from a small amount of that starter plus fresh flour and water, built specifically for one batch of dough.

Many bakers simply use their ripe starter directly, and some recipes use the words interchangeably. Building a dedicated levain, though, lets you control the flour, hydration, timing and acidity of a particular bread without changing the jar you maintain. This guide explains the difference and how to build and time a levain.

Defining the terms

Your starter lives in its jar on a feeding schedule. You use part of it and refresh the rest. Its flour, hydration and temperature are chosen for convenience and stability.

A levain is made a few hours or the night before mixing. You take a spoonful of starter and mix it with a larger amount of fresh flour and water. When the levain is ripe, all of it goes into the final dough, and the starter jar stays separate for next time.

Why build a separate levain

A levain gives you control. You can build it with whole wheat or rye for a darker loaf while keeping a white flour starter, or make a stiff levain for a dough that needs strength. You can scale its size precisely to the recipe instead of guessing how much ripe starter you have.

It also solves timing. A starter fed in the morning might peak at the wrong hour for your schedule. By changing the ratio of starter to fresh flour, you set the levain to peak when you want to mix.

• More flour relative to starter: slower, peaks later
• Warmer spot, around 26°C (78°F): faster
• Cooler spot or stiffer hydration: slower and often more acidic

Example levain builds

A common build is 20 g ripe starter, 50 g flour and 50 g water, giving 120 g of levain at 100 percent hydration, a ratio of 1:2.5:2.5. At about 24°C (75°F) this typically peaks in 4 to 6 hours.

For an overnight build, use 10 g starter with 50 g flour and 50 g water, a 1:5:5 ratio, and leave it at cool room temperature for 8 to 12 hours. The extra flour gives the yeast more to eat and stretches the time to peak. Build a few grams more than the recipe needs to allow for what sticks to the jar.

Knowing when it is ready

A ripe levain has roughly doubled or more, is domed or just starting to flatten on top, smells pleasantly sour and yeasty, and is full of bubbles when you look through the side of the jar. A small spoonful dropped into water often floats, though whole grain and stiff levains may sink even when ready.

Using the levain a little before peak gives a milder, sweeter flavor and good rise. Using it well past peak, once it has collapsed and smells sharp, brings more acidity and can weaken the gluten in the dough.

Using starter directly instead

Many recipes skip the levain and call for active starter. This works well if your starter is healthy and you feed it so it peaks when you are ready to mix. Simply keep back some starter in the jar before adding the rest to your dough.

If a recipe calls for a levain and you prefer to use starter directly, match the weight and hydration. Use 100 percent hydration starter in place of a 100 percent hydration levain, gram for gram.

Common questions

Can I put my whole starter into the dough?

Only if you have saved a small portion in the jar to keep the culture going. Building a separate levain is the easiest way to make sure you never use up the last of it.

Is a levain the same as a preferment?

A levain is a type of preferment. Others, like poolish and biga, are made with commercial yeast rather than a sourdough culture.

How do I adjust a levain for a cold kitchen?

Use a smaller ratio of fresh flour to starter, such as 1:2:2, use slightly warm water, or place the jar in an oven with only the light on. Check often so it does not overshoot peak.