What’s the first thing you look for in a great loaf of sourdough bread? Maybe it’s mix-ins like toasted walnuts or sesame seeds suspended in a loaf, or perhaps it’s something more fundamental: the pure flavor of the grain itself, or the transformation fermentation enables, turning what would be inedible into something that can stop a conversation mid-sentence.
Flavor comes first—always.
Then again, maybe you’re drawn to the visuals first. The dark, burnished crust that crackled when squeezed. A razor-sharp score that bloomed just right in the oven. Or, perhaps the gentle rounded edges that offer a whisper of carefully performed shaping, hands that knew exactly what to do and when to do it.
Or, maybe you’re like many looking for an open crumb, a loaf interior that draws you in with its seductive visual web.
I’ll admit something from the get-go, though: of all the qualities that make sourdough bread memorable, that open crumb is probably the least important. But I’d wager you already knew that.
In short, here are the things I find help you get bread with an open crumb:
- A strong (in terms of protein quality), mostly-white, flour blend
- Ample (but not too much) fermentation
- A higher dough hydration that’s still appropriate for the flour
- A sufficiently developed (strengthened) and gently-handled dough
- A batard (oval shape) can help. Generally, narrow is better than wide
- Proofing to just the right point
We’ll look at each of these as we go through this open crumb sourdough bread guide.
Flavor comes first—always. And while an open crumb tends to obsess those new to the craft, it becomes less important as you continue to bake. But I will say that an open, light, and airy structure isn’t only about looks; it is evidence of what happened beneath the surface: vigorous fermentation, proper dough development, and gentle handling at every turn. It’s a light, even texture with well-distributed holes, free of large gaping caverns surrounded by dense spots.
When the flavor component is there, as it should always be, this kind of texture makes for bread that’s genuinely pleasurable to eat.
In this guide, I’ll walk you through the decisions that lead to a more open crumb, from choosing your flour to finding the right proof. It is not to chase perfection or impress anyone, but to help you understand your dough well enough to create the bread you actually want to bake—and eat.
What Is Open Crumb Sourdough Bread?
When sliced, an open-crumb loaf of bread reveals an interior with many well-distributed holes created during fermentation. The gluten in wheat flour, when properly developed, forms an elastic network that traps carbon dioxide produced by yeast (primarily) and bacteria. This captured gas expands in the oven, creating those characteristic air pockets that give the bread its light, airy texture.
But let’s be clear about what we’re actually after here. When I talk about an open crumb, I’m not referring to bread with gaping holes so large you could lose your sandwich fillings. An appropriately open crumb is about creating a light, even texture throughout the bread, with holes that are well-distributed, and an overall structure that feels tender and airy in your mouth.
But Wait, Is Your Open Crumb Actually Underproofing?
At first glance, the following loaf might look like a successful open crumb sourdough bread, but let’s take a closer look and see what’s really going on. (Spoiler: to me, it’s underproofed.)
Often, a loaf with an “open crumb” is really underproofed bread in disguise. Yes, it’s open, but it’s too open, with large gaping holes and surrounding areas that might be denser and tighter. The loaf above is on the edge of this. It has fewer dense spots, but it still has too many large holes and too much upward rise and oven spring (the score broke open erratically on top).
We all underproof (and overproof!) bread from time to time. Judging the perfect proof point is part of the process that requires a build-up of baker’s intuition (as I call it in my cookbook) to make the right call during bulk fermentation and final proof.
Here’s my criteria for spotting an underproofed loaf of sourdough bread masquerading as a loaf with an open crumb:
- Scattered, large holes (often with strange, snaking or squished shapes)
- Some areas with dense, gummy spots, though the degree of this can vary
- Excessive oven spring (upward rise) with a bottom that may be domed upward in a “U” shape
- Excessive rupturing on the top, even with proper scoring
- A dull, uninteresting crust
- Flat, one-dimensional flavor
In my Instagram post below, I run through a few more of my bakes that were even more clearly underproofed. Notice the denser areas with strange, almost lava flow-like holes moving throughout:
The fix for underproofed dough like this? Give the dough more fermentation time. Let the dough ferment longer in bulk fermentation and/or in its final proof to help even out the holes in the crumb, eliminate dense and gummy spots, and facilitate a more controlled oven spring.
Now let’s look at the things that actually help us get closer to an open crumb. First up, and arguably the most important thing, is choosing the right flour.
Selecting The Right Flour for an Open Crumb
I consider flour to be one of the most important factors when striving for an open crumb. You can mix to the right level of strength, have vigorous fermentation, and proof dough to exactly the right point, but if your flour can’t support larger bubbles, there’s not much you can do about it.
Choose white flour, rather than whole wheat, and try using one with a higher protein content for an open crumb.
Strong white flour—what I often call high-protein flour white flour—has a higher protein content, which means more gluten-forming potential. When you mix and develop the dough, that extra protein creates a more robust elastic network that can expand with the gases created during fermentation without tearing. It’s like the difference between a cheap balloon that pops easily and a quality one that can inflate large and stay intact. The stronger flour gives you more room for error and more capacity to create those open pockets.
But there’s also a limit: if you use flour that’s too strong (for me, anything above 13% protein), you’ll end up with bread that has an open crumb but is chewy and gummy.
I’ve found the sweet spot in my baking to be somewhere between 11% and 13% protein for white flour. Using a high-extraction flour like Type 85 flour, when properly hydrated (read: more water), can also work very well toward an open crumb while also providing excellent flavor.
What about whole wheat flour, though? It’s high in protein.
Know that the more whole wheat flour you add, the more difficult it becomes to achieve an open crumb. But this isn’t a loss because what whole wheat takes away in openness, it gives back in flavor and nutrition. I see it as a trade-off worth making. Just understand that a 50% whole wheat loaf will never be as tall and airy as an all-white flour loaf, and that’s perfectly fine. Adjust your expectations, not your standards.
In short: Choose white flour, rather than whole wheat, and try using one with a higher protein content for an open crumb.
Sourdough Starter Fermentation and Its Effect
Vigorous fermentation in any sourdough bread dough starts with a healthy sourdough starter. Feed yours consistently—I refresh mine twice daily, once in the morning and once at night, and keep it around 74°F to 78°F (23-25°C). You do not need to feed it as often as I do, but I do find that this cadence helps keep my starter strong enough for ample leavening.
For an open crumb, use sourdough starter when it just turns ripe, before it becomes too acidic.
In addition to keeping your starter healthy with regular, warm feedings, it’s important to use your starter right as it turns ripe. Look for these signs of ripeness with a liquid starter:
- Risen noticeably in the jar
- Scattered bubbles on top and sides
- A pleasant sour aroma (not overly acidic)
- Loosened, almost pourable consistency
Try to catch your starter when it’s just ripe rather than waiting for it to continue fermenting. An over-fermented starter brings more active protease enzymes into your final dough, where they’ll continue breaking down gluten throughout bulk fermentation. This is a good thing up to a point, but if left for too long, the result will be a weaker dough structure and a tighter crumb.
(Read on to the proofing section for how these are at play within the main dough, too. 👇🏼)
In short: For an open crumb, use sourdough starter when it just turns ripe, before it becomes too acidic.
Hydration Strategy For an Open Crumb
A higher hydration generally makes it easier to achieve an open crumb. More water creates a more extensible dough that can stretch and expand without tearing, and it generates steam during baking that helps push the crumb open.
But—and this is important—having a higher hydration isn’t a requirement, and it comes with trade-offs. Doughs with more water are harder to handle and require more skill to develop adequate strength (this is where a mechanical mixer really does help). Push the hydration too high for your flour’s capacity, and you’ll end up with dough that’s soupy and structurally weak, no matter how much you strengthen it.
A higher dough hydration can help achieve an open crumb, but it isn’t mandatory.
For my mostly white flour doughs here in arid New Mexico, I typically work between 70% and 80% hydration. But that number is just a number; it’s very relative to the flour I’m using. A high-protein white flour might handle 85% beautifully, while a softer all-purpose flour could struggle at 75%.
The goal is finding the sweet spot: enough water to create a soft, extensible dough that can expand freely, but not so much that you’re fighting to build structure. You’ll know you’ve found it when the dough feels alive in your hands; it’ll be silky, supple, responsive, not overly slack or soupy.
Can you get an open crumb at 70% hydration? Absolutely. Will 80% make it easier? Probably, if you have experience in working with wetter doughs!
In short: A higher dough hydration can help achieve an open crumb, but it isn’t mandatory.
Finding The Sweet Spot: Strengthen The Dough Appropriately
I see dough development, strengthening, mixing, and handling all related to the strength of a dough and its ability to hold and retain its structure even when deformed during processing.
Sufficient gluten development is important when seeking an open crumb. When you mix dough, you’re building a network that can trap gas, stretch outward, and form pockets we call the crumb. Under-strengthen the dough, and those pockets are weak and could collapse into a tight, dense crumb.
But there’s a limit. Over-mix and you create dough that’s so elastic it fights expansion. The gluten becomes too tight, resisting the very stretch you need for an open interior. You’re back to a closed crumb, just from the opposite direction.
Most home bakers, especially those mixing by hand, tend to underdevelop their dough. I see this often. During mixing, the dough feels tighter and more elastic, but it’s not quite smooth enough and doesn’t hold its shape well.
Try this: Mix for a few minutes longer than feels comfortable. Really work the dough, whether by repeatedly folding it in the bowl, using slap and folds, or mixing it in a stand mixer on medium speed. You’re looking for dough that’s smooth, elastic, and holds its shape when you stretch it.
At the end of mixing, it will almost pass the windowpane test: a thin membrane you can stretch without tearing. If you’re unsure, err on the side of more mixing.
In short: Strengthen the dough enough to develop the gluten, but not so much the dough is overly elastic and rubbery.
Gentle Preshaping and Shaping Helps Preserve Structure
Generally, when working toward an open crumb, I like to be as gentle with the dough as possible.
Your dough contains thousands of gas pockets, each one surrounded by gluten walls you’ve built through mixing and folding. When you handle dough roughly—pressing too hard during shaping, slapping it against the counter—you rupture these bubbles. They break into smaller versions of themselves, and your open crumb becomes tight and uniform.
This is why gentle handling matters, especially during preshaping and final shaping. The dough has spent hours building up a delicate structure. If you’re too forceful, you’re kind of undoing this.
In short: Be gentle with the dough to help preserve its structure.
Why An Oval Loaf (Batard) Usually Has a More Open Crumb
In my experience, an oval batard consistently produces a more open interior than a round boule. I think two factors explain this.
First, batard shaping requires less force. When shaping a boule, you’re often tucking and creating tension all around the dough, which can compress those developing gas pockets. With a batard, you’re rolling the dough into a cylinder in a more linear motion that’s gentler and preserves the airy structure you’ve built during bulk fermentation.
Second, the shape itself bakes differently. A batard’s thinner, elongated profile allows oven heat to penetrate faster and more evenly. For an even more extreme example, think about a long, thin baguette compared to a large miche: the baguette, with its slim cross-section, develops that wild, irregular crumb with dramatic holes. The miche, thick and round, tends toward a tighter, more uniform interior. Potentially the same dough with different geometry and thus different results.
This isn’t to say you can’t get an open crumb with a boule—you absolutely can. But if you’re struggling with a tight interior and you’ve been shaping rounds, try a batard next time. The shape might be working against you.
See my guide on shaping an oval batard for instructions on performing this shaping technique correctly.
Proofing to Perfection
The final proof is where everything comes together. Your dough has been strengthened, shaped, and now fermentation is transforming it from dense to light, building the structure that will become your crumb.
There’s a narrow window you’re aiming for: the point where your dough has risen 75% to 80% of its full height. You want to leave some reserve strength so the dough can finish expanding in the oven’s heat. This final push (oven spring) is what opens up the crumb in those first crucial minutes of baking.
Push the proof too far, and the gluten network begins to break down. Protease enzymes that have been working throughout fermentation eventually weaken the dough’s structure. The dough loses its ability to trap gas, and what should be a dramatic rise in the oven becomes a sluggish spread. You’ll get flavor (I often say I actually prefer overproofed bread to under!), but the interior will be tighter and denser.
What to look for in sufficiently proofed dough: It should feel alive. Puffy, light, yielding but not weak. When you gently press a finger into it, it should pass the poke test: the impression should slowly spring back. Not immediately (under-proofed), not stay completely indented (over-proofed).
If the dough still feels tight and springs back quickly, give it another 30 minutes and check again. If it feels soft and weak, or you see large bubbles pushing up beneath the surface, it’s time to quickly bake.
Bonus: For Increased Extensibility, Perform an Autolyse
The autolyse technique, which is just mixing flour and water, then letting it rest before adding salt and your starter or levain, can significantly increase your dough’s extensibility. During this rest, enzymes naturally present in the flour begin gently breaking down protein bonds, making the dough more elastic and less likely to spring back.
I particularly use an autolyse when working with high-protein white flour, which tends to have significant elasticity. That rest period tames the flour’s natural resistance, allowing the dough to expand more freely during fermentation and baking. The result is a dough that can stretch to accommodate all those gas bubbles without tearing or fighting back.
For open crumb bread, this increased extensibility matters. A dough that’s too elastic will resist expansion, limiting how large those air pockets can grow. An autolyse of even 30 minutes to an hour can shift that balance, giving you a dough that’s both strong and supple.
In short: An optional autolyse can help gain extensibility, especially with strong flour.
Putting It All Together For an Open Crumb—Or Not
Over the past decade of baking, I’ve learned that there’s no single trick that will magically make open crumb sourdough bread. This type of crumb is the sum of many deliberate choices: flour selection, starter timing, hydration levels, gentle handling, and proper proofing. Each step influences the next, and understanding these connections is an important facet of baking.
As I always say, experiment in your kitchen! Try different hydration levels with the same flour. Use your starter at different stages of ripeness. Shape more gently one day, more firmly the next. Take baking notes, compare results, and trust what you observe.
While I prioritize flavor above all else, texture does matter. A well-aerated crumb enhances every bite, whether you’re spreading butter, building a sandwich, or simply tearing into a warm slice on its own. The level of aeration, though, is ultimately up to you. Some folks love a tighter crumb—and that’s totally okay and appropriate!
But here’s what I want you to remember: delicious bread comes in many forms. A dense, hearty loaf packed with whole grains can be just as satisfying as an airy, open-crumbed batard. Sometimes more so. The goal isn’t perfection or Instagram-worthy slices. It’s bread that makes you happy to bake and even happier to eat.
Keep at it. The bread will teach you everything you need to know.
Open Crumb Bread FAQs
How can I avoid an open crumb bread?
I get it, not everyone likes a very open loaf, and honestly, not every style of bread is appropriate for it, either. Performing a gentle degas of the bread dough during shaping can help redistribute gases throughout the dough, resulting in fewer large holes. To degas, just before final shaping, use a flat hand and pat the dough down from top to bottom to gently flatten the dough.
My bread has a nice open crumb. Why is it gummy or tough?
This can be a result of using flour that’s overly strong (too high a protein percentage). I find that strong white flour often has a tough, rubber-like mouthfeel when eating.
What’s Next?
For my go-to open crumb bread, look no further than My Best Sourdough Recipe, a transformative bread I developed a while back, resulting in a loaf with a creamy, open crumb that’s a showstopper.
