75 Percent Hydration Sourdough Bread Recipe: Foil-Sealed Crust With Open Crumb Magic

Mastering a 75 percent hydration sourdough bread recipe transforms your kitchen into a bakery—crispy foil-sealed crusts with an open, airy crumb that defies expectations. The secret lies in balancing water-to-flour ratio and fermentation time, creating a loaf that's both structurally sound and irresistibly tender.

After years of perfecting this technique, I've developed a method that delivers consistent results even for beginners.

This recipe focuses on the delicate dance between hydration and gluten development, where 75 percent hydration creates a lighter, more open crumb than traditional sourdough. The foil-sealing technique during baking ensures a crispy exterior without compromising the delicate interior structure.

What sets this apart is the predictable oven spring and reliable crust development, even in less-than-ideal baking conditions.

By following this method, you'll achieve a loaf with a golden, crackling crust that gives way to an open, irregular crumb filled with pockets of air. The flavor develops depth through proper fermentation, resulting in a bread that's both satisfying to eat and impressive to serve.

This is the kind of sourdough that makes people ask for your recipe—and your kitchen smells like a bakery the whole time.

The beauty of this approach is its flexibility—you can adapt it for sandwiches, toast, or even French toast. Once you've mastered the 75 percent hydration technique, you'll never go back to heavier doughs. Let's get started on creating your perfect loaf.

Ingredients for 75 hydration sourdough bread

Precision ingredients for a bakery-quality loaf—where hydration meets artistry.

The flour is non-negotiable here. King Arthur or Bob's Red Mill unbleached flour has the protein balance for optimal gluten development at 75% hydration. If you're using a different brand, check the protein content—aim for 10-11%. Your sourdough starter should be 100% hydration and bubbly with a slight tang. For the yeast, Fleischmann's active dry is reliable, but ensure it's fresh (test by dissolving a pinch in warm water—it should foam within 5 minutes). The Diamond Crystal kosher salt is preferred because its coarser grains dissolve more predictably than table salt.

No vital wheat gluten? Substitute with an extra 1 tbsp flour, though the texture won't be identical. Running short on olive oil? Avocado oil works equally well—just avoid anything with a strong flavor like sesame. For the water, filtered is ideal, but tap water will suffice if your local water isn't heavily chlorinated. The ice water at the end isn't just for shaping—it helps tighten the gluten structure for that perfect oven spring. If your starter is sluggish, feed it 12 hours before using (equal parts flour and water by weight) to ensure it's at peak activity.

Store your starter in the fridge between bakes—it'll last 2-3 weeks if fed weekly. The flour should be kept in an airtight container in a cool, dark place for up to 6 months. Once baked, the loaf stays fresh for 3-4 days at room temperature, wrapped in a clean kitchen towel (better than plastic for moisture retention). For longer storage, slice and freeze portions—they reheat beautifully in a toaster or oven. The foil-sealed crust technique means you can reuse the foil for up to 3 bakes before it loses its crispiness.

Step-by-step instructions for 75% hydration sourdough bread

Master the art of sourdough with this precise method—crisp crust, open crumb, and perfect rise every time.

In a large mixing bowl, combine the 500 g unbleached all-purpose flour, 1 tbsp vital wheat gluten, 1.5 tsp diamond crystal kosher salt, and 0.25 tsp active dry yeast. Whisk thoroughly to eliminate any lumps. Create a well in the center and add the 1 cup active sourdough starter and 1 tbsp granulated white sugar. Pour in the 375 ml distilled water and 1 tbsp extra-virgin olive oil, then mix with a dough whisk or wooden spoon.

Once combined, turn the dough onto a lightly floured surface and perform 10 sets of stretch-and-folds over 30 minutes. This technique strengthens the gluten structure, which is critical for the open crumb structure we're targeting. The dough should become smooth and elastic, with a slight resistance when pulled. If it feels too sticky, add a few grams of flour—but don't overdo it, as excess flour can interfere with hydration.

Place the dough back in the mixing bowl, cover loosely with a damp kitchen towel, and let it bulk ferment at 75-78°F (24-26°C) for 4-6 hours. I use a proofing box for consistency, but a warm oven with the light on works too. The dough should roughly double in size and show 30-40% overproofing—meaning it should have expanded significantly but still feel slightly underproof when gently pressed.

During fermentation, perform 2 sets of stretch-and-folds at 1-hour intervals. These folds help develop gluten and ensure even fermentation. The dough should pass the "poke test"—when you gently press your finger into the dough, it should spring back slowly (about 1-2 seconds) rather than immediately. This indicates proper fermentation without overproofing.

Turn the dough onto a lightly floured surface and shape it into a tight boule. To do this, gather the dough from the edges toward the center, sealing the seam tightly. Rotate the dough 180 degrees and repeat until you achieve a smooth, taut surface. Place the shaped boule seam-side down on a piece of parchment paper dusted with 2 tbsp cornmeal. This prevents sticking and adds texture to the crust.

Cover the dough with the 1 sheet aluminum foil and refrigerate for 12-16 hours. Cold fermentation slows yeast activity, allowing for better flavor development and a more controlled rise. The dough should rise 50-75% during this time. When ready to bake, remove the dough from the fridge and let it sit at room temperature for 1 hour to relax the gluten structure before scoring.

Preheat your oven to 450°F (232°C) with a Dutch oven inside for 1 hour. Remove the Dutch oven and place the dough inside, then score the top with a sharp razor blade in a simple crosshatch or basketweave pattern. Immediately place the lid on the Dutch oven and bake for 20 minutes. This steam phase creates that coveted crisp crust while maintaining an open crumb structure.

After 20 minutes, remove the lid and bake for an additional 25-30 minutes until the internal temperature reaches 205-210°F (96-99°C). The bread should have a deep golden-brown crust with a hollow sound when tapped on the bottom. For extra shine, brush the crust with ice water just before removing from the oven—this creates that beautiful sheen and enhances crust texture.

Remove the bread from the Dutch oven and place it on a wire rack to cool completely for at least 2 hours. This resting period allows the crumb to set properly and prevents a gummy texture. The internal temperature should drop to below 140°F (60°C) before slicing. Use a serrated bread knife and cut against the grain for clean slices that showcase the open crumb structure.

The final result should be a loaf with a crisp, crackly crust that gives way to a light, airy crumb with large, irregular holes. The flavor should be tangy from the sourdough starter, with a subtle sweetness from the sugar and a satisfying chewiness from the gluten development. Serve warm with butter or olive oil for the ultimate experience.

Essential equipment for great 75 hydration sourdough bread

Dutch Oven Essentials

The Dutch oven is your secret weapon for achieving that bakery-style crust and open crumb. I recommend a 5-6 quart enameled cast iron like the Le Creuset Signature Round Dutch Oven—it retains heat beautifully and creates the perfect steam environment.

If you're on a budget, the Lodge 5.5 Quart Dutch Oven offers the same performance without the premium price. The key is preheating it for at least 1 hour before baking to ensure consistent heat distribution. 🔥

Proofing Box Must-Have

A proofing box is non-negotiable for consistent fermentation temperatures. My go-to is the Proof Box by Proof Baking—it maintains 75-78°F (24-26°C) with precision, eliminating guesswork. For a DIY alternative, use a large plastic tote with a heating pad set to low and a thermometer to monitor temps.

Without controlled proofing, your dough may rise unevenly or overproof, ruining the crumb structure.

Digital Thermometer

Never bake without a digital instant-read thermometer like the ThermoWorks Thermapen ONE. It helps monitor dough temperature during bulk fermentation (ideal range: 75-78°F) and internal bread temperature at the end (205-210°F).

For Dutch oven baking, I also use it to check oven temperature—450°F is critical for that perfect crust. A cheap thermometer can leave you with underproofed dough or overbaked bread.

Stretch-and-Fold Tools

For stretch-and-folds, I use dough scrappers (like OXO Good Grips) to handle the dough without sticking. Alternatively, a wet rubber spatula works well. The goal is to develop gluten without tearing the dough.

If your kitchen tools are too dry, wet them slightly—this prevents sticking and makes handling easier. A damp towel under your work surface also helps prevent the dough from sticking while you shape it.

Scoring Tools

A sharp razor blade or lamé is essential for scoring your dough. I prefer a Japanese-style bread knife like the Global GII—it glides through the dough effortlessly. Dull blades tear the dough, leading to messy crusts.

Score just before baking to release steam and direct the oven spring. A simple crosshatch or basketweave pattern works best for this hydration level.

Cooling Rack

Never cool your bread on a plate or counter—it traps steam and makes the crumb gummy. A wire cooling rack (like the OXO Good Grips) allows air circulation, ensuring the crust sets properly. For even better results, place the rack on a baking sheet to catch any crumbs.

The bread should cool for at least 2 hours before slicing—this patience pays off with clean slices and maximum flavor development. ✨

Frequently asked questions