Does higher hydration create open crumb?

Not automatically. Higher hydration increases the *potential* for expansion, but only if the flour is strong enough to hold that water and the gluten structure is developed enough to trap the gas.

What hydration is best for All-Purpose flour?

For standard All-Purpose flour, the sweet spot is typically 65% to 72%. Going above 75% often leads to flat, gummy loaves because the protein content cannot support the water weight.

Why is my high hydration dough flat?

A flat high-hydration loaf usually means the gluten structure degraded (over-fermentation) or the flour wasn't strong enough for the water amount. It collapsed sideways instead of rising up.

Hydration vs Flour Type: What Actually Creates Open Crumb (And Why Most Advice Is Wrong)

If higher hydration automatically created open crumb, every 85% hydration loaf would look like Swiss cheese.

They don’t.

In fact, many of the flattest, densest sourdough loaves come from dough that is too wet, not too dry.

So what really creates open crumb? Is it hydration? Is it flour type? Is it technique?

The answer is uncomfortable for the internet but liberating for bakers: Open crumb is not caused by high hydration alone. It’s created when hydration matches flour strength, fermentation, and structure.

What “Open Crumb” Actually Means

Open crumb does not mean "random giant holes" (often called "Fool's Crumb"). It does not mean a loaf that collapses sideways.

True Open Crumb Is:

Evenly distributed alveoli (air pockets).
Thin but elastic cell walls.
Vertical lift.
Internal structure that supports expansion.

If your loaf has one giant tunnel and dense gummy zones, that’s not open crumb. That’s structural failure.

The Big Myth: “Just Increase Hydration”

This advice persists because it’s half true. Hydration does increase potential gas expansion.

But potential ≠ result.

When hydration exceeds what the flour can support, gluten weakens faster than gas pressure builds.

Result: Dough spreads instead of rising.
Outcome: A flat pancake.

More water ≠ More structure.

🧮 Calculate, Don't Guess

Small changes matter. +2% hydration can collapse a dough. Use our tool to dial it in precisely.

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Flour Type: The Hidden Limiter

Hydration never exists in isolation. It only works relative to flour strength.

1. All-Purpose Flour (AP)

Sweet Spot: 65% – 72%
Behavior: Weakens quickly at higher hydration.
Risk: Going above 75% usually causes spread and gumminess.

2. Bread Flour

Sweet Spot: 68% – 78%
Behavior: Stronger gluten, better gas retention.
Verdict: Most "open crumb" home loaves live here.

3. High-Protein / Artisan Flour

Sweet Spot: 72% – 82%
Behavior: Can handle long fermentation and supports dramatic oven spring.
Verdict: Hydration here works because the flour allows it.

4. Whole Wheat Flour

Sweet Spot: Higher water needed, but...
Behavior: Bran cuts gluten strands.
Result: High hydration does not equal open crumb with whole wheat; it often just makes it heavy.

⚠️ Protein % Is Misleading

Two flours can have the same 12% protein but behave completely differently. Gluten quality matters more than quantity. A cheap high-protein flour might have extensibility but zero elasticity (it stretches but doesn't bounce back).

Why High Hydration Can Make Crumb Worse

At excessive hydration:

Gluten becomes too extensible: It stretches too easily.
Loss of Recoil: Dough loses its elastic "snap back."
Tearing: Gas expands without resistance, tearing the structure.

This is why many "85% hydration" loaves look worse than well-made 72% loaves.

Fermentation: The Missing Variable

Hydration and flour only matter if fermentation is correct.

Too Short: Not enough gas = Tight crumb.
Too Long: Gluten degrades = Dough collapses.

High hydration accelerates fermentation. This means you have a shorter window for bulk fermentation. Many bakers blame the flour when the real issue is over-fermentation caused by the water speeding things up.

(See our guide on Troubleshooting Flat Sourdough for fermentation fixes.)

The Real Open Crumb Formula

Open crumb happens when four things align:

Hydration matches flour strength.
Gluten is developed before fermentation peaks.
Fermentation stops before gluten degrades.
Structure directs gas upward (shaping).

Miss any one, and hydration won’t save you.

Stop Chasing Numbers

The best open crumb loaf is not the wettest one. It’s the one where flour strength and hydration are balanced.

If you’re still guessing hydration, you’re baking blind.

🍞 Open Sourdough Calculator