Welcome to The Leviette Method.
Chapter 1: Creating Your Starter

Understanding Fermentation & Hydration

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The Magic of Fermentation

Fermentation is the quiet heartbeat of sourdough baking—a slow, natural process that breathes life into your dough. It’s during this stage that wild yeast and lactic acid bacteria, nurtured in your starter, begin to feast on the flour’s sugars. As they work, they release carbon dioxide, which creates the airy crumb, and organic acids, which lend sourdough its distinctive, tangy flavor.

But fermentation is more than just rise and flavor. It also gently breaks down gluten and phytic acid, improving digestibility and unlocking nutrients within the grain. It’s the very soul of the bread—a delicate transformation that requires patience, intuition, and care.

Think of fermentation as your quiet collaborator—working in the background, building strength, depth, and character in every loaf.

Timing is Everything

Fermentation is a living process, and its pace is affected by time, temperature, and hydration. A warm environment (around 24–27°C / 75–80°F) speeds things up, while a cooler room slows things down. For a typical sourdough loaf, bulk fermentation (the first rise after mixing) can last anywhere from 4 to 6 hours, though colder temperatures may stretch this longer.

You’ll know fermentation is progressing well when your dough becomes puffier, smoother, and slightly domed on top. If you gently jiggle the bowl, the dough should wobble with life. Under-fermented dough feels dense and tight; over-fermented dough loses its strength and becomes slack, sticky, and sour.

Hydration: The Water-to-Flour Ratio

In baking, hydration refers to how much water is in your dough compared to the flour, expressed as a percentage. A dough made with 500g flour and 375g water has a 75% hydration level.

Hydration has a profound effect on the dough’s behavior, handling, and final texture:

  • 60–65% hydration:

    • Characteristics: Firmer, easier to handle

    • Results in the loaf: Tight crumb, less open holes

  • 70–75% hydration:

    • Characteristics:Balanced, beginner-friendly

    • Results in the loaf: Open crumb, moist interior

  • 80%+ hydration:

    • Characteristics:Very wet, advanced handling

    • Results in the loaf: Large, irregular holes, custardy texture

Leviétte recommends starting at 75% hydration—a beautiful middle ground that offers softness, elasticity, and structure, while still being approachable for first-time bakers.

How Hydration Affects Flavor & Feel

  • Higher hydration allows for a longer fermentation and encourages a more open, airy crumb with glossy holes. It produces a moist, chewy texture and intensifies the tangy flavor.

  • Lower hydration creates a tighter crumb and more compact loaf—still delicious, but with a denser bite and milder flavor.

Hydration also affects how you handle the dough. Higher hydration doughs feel stickier and more elastic but reward you with that signature “artisan” look and feel.

Flour Matters Too

Different flours absorb water differently. Whole wheat and rye flours are more absorbent than white flour, meaning they require more water to achieve the same texture. Adjust accordingly and trust how your dough feels beneath your fingertips—it should be soft, pliable, and just tacky, not wet or soupy.

A Gentle Balance of Art and Science

There is no single "perfect" formula for fermentation and hydration—it’s a dance of variables, a dialogue between baker and dough. With time, you’ll come to recognize the signs of good fermentation and develop a feel for how much water your flour truly needs.

The beauty of sourdough is that no two bakes are ever the same—each one reflects the rhythm of your kitchen, the mood of your hands, and the soul of the bread you’re creating.

FAQ

  • Fermentation is the slow, natural process where wild yeast and beneficial bacteria in your starter feed on the flour’s sugars. This activity produces gas (which makes your dough rise) and acids (which build flavor). It’s the quiet engine behind every good sourdough loaf.

  • The sweet spot is around 75–78°F (24–26°C). If it’s cooler, fermentation will take longer—just give your dough more time. If it’s warmer, things may move too quickly, which can lead to overproofing. Time and temperature always work together.

  • Hydration refers to the ratio of water to flour in your dough, expressed as a percentage. For example, 375g of water with 500g of flour equals 75% hydration. Higher hydration leads to a more open crumb, but it also makes the dough stickier and more delicate to handle.

  • We recommend starting with 75% hydration—it strikes a balance between softness, structure, and ease of handling. Once you’re more comfortable, you can experiment with higher hydration for more open, airy crumb textures.

  • Every kitchen is different. Temperature, flour type, hydration, and even altitude can affect fermentation speed. It’s best to use visual cues—look for a dough that has risen noticeably, feels puffy to the touch, and shows bubbles beneath the surface.

  • Absolutely. You can use cooler water, reduce the amount of starter in your dough, or place the dough in the fridge to retard fermentation. Slowing things down often improves flavor and gives you more control over your schedule.