Why Does My Sourdough Burst on the Side?
You score your loaf, place it into a hot oven, and wait for that beautiful rise every sourdough baker hopes to see.
The bread expands, but something isn't right.
Instead of opening neatly along the score, it tears open on one side. Sometimes the split is small. Other times it runs almost the entire length of the loaf.
It may look dramatic, but this isn't just a cosmetic problem.
A side burst is your bread telling you that the expanding gases couldn't escape where they were supposed to.
The Score Didn't Become the Weakest Point
A score acts like a planned expansion joint.
As the loaf rises in the oven, the pressure inside increases. The score should open first, giving the bread a controlled place to expand.
If that doesn't happen, the pressure searches for another exit.
The weakest area of the crust eventually gives way, and the loaf bursts along the side.
Underproofing Is the Most Common Cause
The most common reason for side bursting is underproofing.
The dough still has a great deal of energy left when it enters the oven.
As the yeast produces one final burst of gas, the loaf expands rapidly.
If fermentation wasn't complete, the pressure can become greater than the score is able to release, causing the bread to split somewhere else.
Other signs of underproofing often include:
- strong oven spring;
- a dense crumb with uneven holes;
- thick areas beneath the crust;
- a loaf that feels tight before baking.
The Score Was Too Shallow
Sometimes the dough is perfectly proofed, but the score simply isn't deep enough.
A shallow cut may begin opening, then quickly seal as the crust dries.
Once that happens, expanding gases need another escape route.
A confident score, made just before baking, usually gives much better results than several hesitant shallow cuts.
Surface Tension Was Uneven
Good shaping creates even tension across the surface of the dough.
If one side is much tighter than the other, the loaf may naturally burst at its weakest point during oven spring.
This is why consistent shaping is just as important as scoring.
Not Enough Steam
Steam keeps the crust flexible during the first stage of baking.
Without enough steam, the surface begins hardening too early.
The expanding loaf then struggles to push through the score and may break open somewhere else instead.
Dutch ovens and properly steamed ovens greatly reduce this problem.
A Cold Oven Can Also Contribute
If the oven hasn't fully reached baking temperature, the loaf rises more slowly.
Instead of one strong, controlled expansion, pressure builds unevenly.
Combined with shallow scoring or underproofing, this can increase the chance of side bursting.
How to Prevent Side Bursting
Most side bursts can be avoided by paying attention to a few key details:
- allow the dough to proof fully;
- score confidently with a sharp blade;
- shape the loaf evenly;
- bake in a fully preheated oven;
- create enough steam during the first part of the bake.
Often, improving just one of these steps is enough to solve the problem.
A loaf that bursts on the side isn't ruined.
In fact, it often tastes just as good.
But the unexpected split tells you something important about fermentation, scoring, or baking conditions.
Once you learn to recognize those clues, you'll begin seeing your score open exactly where you intended—and your loaves will become more consistent with every bake.
06.08.2026
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