Why Is My Sourdough Gummy Inside? Every Fix I Know

You did everything right. Or at least you think you did. The loaf looks gorgeous from the outside. Golden crust, nice ear, good shape. You wait what feels like a reasonable amount of time, grab a bread knife, cut into it, and there it is: a wet, sticky, gummy mess in the middle. The crumb clings to the knife. It squishes instead of slicing cleanly. It tastes doughy and heavy.

This is probably the most common frustration in sourdough baking. I dealt with gummy crumbs for months when I was starting out, and I can tell you that the cause is almost always one of six things. Sometimes it is a combination of two or three. Let me walk through every one of them so you can figure out exactly what is going on with your bread.

Cause #1: You Cut the Bread Too Soon

This is the most common cause of gummy crumb, and it is the easiest to fix. If you cut a loaf of sourdough bread while it is still warm, the interior has not finished setting. The starches are still gelatinous. The moisture has not redistributed. What you are seeing is not under-baked bread. It is bread that has not finished its process.

Baking does not end when you pull the loaf from the oven. The internal temperature of a fresh loaf is over 200F. As it cools, the starch molecules undergo a process called retrogradation. They firm up, lock in moisture evenly, and create the structure that allows the crumb to hold its shape when sliced. Cut too early and you interrupt this process before it is complete.

Cause #2: Under-Baking

The second most common cause. Sourdough takes longer to bake through than most people expect, especially if you are coming from commercial yeast recipes. The dense, moist crumb of sourdough needs sustained heat to fully cook the starches in the center.

Here is how to check if under-baking is your problem:

• Use an instant-read thermometer. Insert it into the center of the loaf when you think it is done. You want 205-210F for a standard sourdough loaf. If it reads below 200F, it needs more time
• Tap the bottom. A fully baked loaf sounds hollow when you tap the bottom. A dull thud means the center is still wet
• Check the crust color. A properly baked sourdough should be deep golden brown, almost mahogany. If it is pale gold, it is not done. People dramatically under-bake because they are afraid of burning the crust

Cause #3: Too Much Hydration for Your Flour

High hydration is trendy in the sourdough world. Everyone is chasing the 80%, 85%, even 90% hydration open crumb shots they see online. But here is the thing: high hydration only works if your flour can handle it. And if your technique matches it.

All-purpose flour maxes out around 72-75% hydration before it starts creating problems. Bread flour can handle 75-80%. Specialty high-protein flours can go higher. If you are using grocery store all-purpose flour at 80% hydration because a recipe told you to, you are going to get gummy bread. The flour simply cannot absorb and retain that much water while still creating a structured crumb.

Drop your hydration by 3-5% and see what happens. A loaf at 72% hydration with a fully baked, properly cooled crumb will beat an 80% hydration gummy disaster every single day of the week.

Cause #4: Over-Fermentation

Over-fermented dough produces a gummy crumb for a specific biological reason. When dough ferments too long, the organic acids produced by the bacteria break down the gluten structure. The gluten goes from a strong, stretchy network that can hold gas and create structure to a weak, mushy mess that collapses and compacts.

Signs your dough over-fermented:

• The dough felt very loose and jiggly when you shaped it
• It spread flat after shaping instead of holding its shape
• There was minimal oven spring
• The crumb is gummy AND dense at the same time, with large irregular holes near the top and compressed layers at the bottom

If this sounds like your bread, reduce your bulk fermentation time. Aim for a 50-75% volume increase rather than a full double. Use a clear container so you can actually see the volume change. And pay attention to temperature. A kitchen that is 80F will ferment dough twice as fast as one that is 68F.

Cause #5: Insufficient Gluten Development

Gluten is what gives bread its structure. Without enough gluten development, the crumb cannot hold its shape and collapses into a gummy, dense texture after baking. This is different from over-fermentation, which destroys gluten that was already developed. This is about never developing it properly in the first place.

Signs of insufficient gluten:

• The dough never passed the windowpane test during bulk fermentation
• It felt slack and extensible but not elastic (stretches easily but does not spring back)
• The crumb has very small, uniform holes with a cake-like texture
• The bread is dense throughout, not just in the center

The fix: more stretch and folds during bulk fermentation, or a longer autolyse before adding the starter. Some bakers do a series of slap-and-fold or coil folds to build strength. The goal is a dough that feels smooth, elastic, and holds its shape when gently pulled. If your dough feels like pancake batter after bulk fermentation, you need more development.

Cause #6: Oven Temperature Issues

Your oven lies to you. Almost every home oven is off by 15-50 degrees from what the dial says. If your oven runs cold, your bread bakes at a lower effective temperature, which means the center takes longer to reach full temperature, which means gummy crumb even at the correct baking time.

Buy an oven thermometer. They cost a few dollars and will transform your baking. Place it on the rack next to your Dutch oven and check the actual temperature before loading your bread. If your oven says 450F but the thermometer reads 410F, you know you need to set the dial to 490F to get true 450F.

The Diagnostic Flowchart

When you get a gummy loaf, work through these questions in order:

1. Did you wait at least 2 hours before cutting? If not, that is probably your answer. Bake the same recipe again and wait. Problem likely solved
2. Was the internal temperature above 205F when you pulled it? If you did not check, get a thermometer and bake it 5-10 minutes longer next time
3. Is your hydration above 75%? If yes and you are using all-purpose flour, drop to 72% and try again
4. Did the dough hold its shape after shaping? If it spread flat, you over-fermented. Reduce bulk time
5. Did the dough feel developed and elastic during bulk? If it felt slack and loose, add more stretch and fold sets
6. Is your oven temperature accurate? Check with an oven thermometer