Why Does My Sourdough Bread Collapse Common Mistakes And How To Fix Them

Sourdough bread is a rewarding craft, but few things are more frustrating than pulling a beautifully risen loaf from the oven only to watch it deflate moments later. A collapsed sourdough can look like failure, but in most cases, it’s simply a sign of one or more technical missteps during the process. The good news? These issues are almost always preventable. Understanding the science behind gluten development, fermentation, and baking mechanics allows bakers to diagnose problems and adjust their technique for reliable results. Whether you're a beginner or have been baking for years, mastering these nuances will transform your loaves from floppy failures to tall, airy masterpieces.

Understanding Why Sourdough Collapses

A collapsing sourdough loaf typically occurs when the internal structure cannot support the expansion created by steam and gases during baking. This structural weakness may stem from underdeveloped gluten, overproofing, poor scoring, or incorrect baking temperature. Unlike commercial yeast breads, sourdough relies entirely on natural fermentation and physical dough strength, making timing and handling critical. The collapse might happen in the oven (often called “gassy collapse”), immediately after removal, or even hours later as the crumb settles.

The ideal sourdough loaf has a strong gluten network that traps carbon dioxide produced by wild yeast and bacteria. During baking, this gas expands, and steam lifts the crust—this is known as \"oven spring.\" If the dough lacks strength or is too fragile, it can't withstand this pressure and deflates. Identifying where in the process this breakdown occurs is key to fixing it.

Tip: Perform the \"windowpane test\" before bulk fermentation ends—if you can stretch a small piece of dough thin enough to see light through without tearing, your gluten is well-developed.

Common Mistakes Leading to Collapse—and How to Fix Them

1. Overproofing the Dough

Overproofing is the single most common cause of collapsed sourdough. When dough proofs too long, the gluten structure begins to break down as acids accumulate and gas production peaks then declines. The result is a fragile dough that expands rapidly in the oven but lacks the integrity to hold its shape.

How to identify overproofing: The dough feels excessively soft, jiggly, or doesn’t spring back when gently poked. It may have large air pockets near the surface or collapse when transferred to the baking vessel.

Solution: Reduce proofing time. Use the \"poke test\" cautiously—press a fingertip about half an inch into the dough. If it springs back slowly and leaves a slight indentation, it's ready. If it doesn’t spring back at all, it's overproofed. For room-temperature proofing, start checking after 3–4 hours; for cold retardation, 12–16 hours in the fridge is usually sufficient, depending on starter strength.

2. Underdeveloped Gluten Structure

Without a strong gluten matrix, dough cannot trap gas effectively. This often happens when mixing is insufficient, or when using high hydration without proper strengthening techniques like stretch and folds.

Solution: Incorporate 3–4 sets of stretch and folds during the first 90 minutes of bulk fermentation. Alternatively, use a stand mixer with a dough hook for 5–7 minutes on medium speed to develop strength early. Autolyse (resting flour and water for 30–60 minutes before adding salt and starter) also improves gluten formation.

3. Incorrect Hydration for Your Flour

Too much water relative to flour weight weakens dough structure. Many beginners jump into 80%+ hydration recipes without realizing their flour can’t support it. All-purpose flour absorbs less water than high-protein bread flour, so hydration must be adjusted accordingly.

Solution: Start with 70–75% hydration if using all-purpose flour. Increase gradually as you gain skill. Weigh ingredients precisely using a kitchen scale. If dough feels soupy or spreads excessively during shaping, reduce hydration by 5% in your next bake.

Flour Type	Recommended Max Hydration	Notes
All-Purpose Flour	75%	Limited gluten strength; best for beginners
Bread Flour	80–85%	Higher protein supports wetter doughs
Whole Wheat Flour	70–75%	Absorbs more water but weakens gluten
Spelt or Rye Blends	65–70%	Very low gluten; requires blending with strong flour

4. Poor Scoring Technique

Scoring isn’t just decorative—it controls where the loaf expands during oven spring. Poor cuts can lead to unpredictable bursting, which destabilizes the loaf. Shallow or jagged scores don’t open cleanly, forcing pressure to escape elsewhere and potentially causing collapse.

Solution: Use a sharp lame or razor blade. Make decisive, swift slashes at a 30–45 degree angle, about ½ inch deep. For round boules, a single deep slash or cross pattern works well. Practice consistency in depth and angle. Score right before baking to prevent skin formation.

“Proper scoring is like releasing a safety valve—it directs expansion rather than fighting against it.” — Daniel Leader, author of *Local Breads* and founder of Bread Alone Bakery

5. Inadequate Oven Spring Environment

Oven spring depends on three factors: heat, steam, and proper preheating. Without sufficient initial heat, the dough won’t expand quickly enough to set its structure. Lack of steam causes the crust to harden too early, restricting rise.

Solution: Preheat your Dutch oven or baking stone for at least 45 minutes at 450°F (230°C). Add steam by placing a metal tray with lava rocks in the oven and pouring 1/2 cup of boiling water onto it just after loading the bread. Alternatively, cover the Dutch oven during the first 20 minutes of baking to trap moisture.

Tip: Always preheat your baking vessel. Cold ceramic or metal absorbs heat from the dough, killing oven spring before it starts.

Step-by-Step Guide to Prevent Collapse

Follow this sequence to build a resilient, high-rising sourdough loaf:

1. Autolyse: Mix flour and water; rest 30–60 minutes. This hydrates flour and jumpstarts gluten formation.
2. Add Starter and Salt: Mix in levain and salt. Perform 3–4 sets of stretch and folds over 90 minutes.
3. Bulk Fermentation: Let rise at room temperature (74–78°F) for 3.5–5 hours, until increased by 50–75%, passes windowpane test, and shows bubbles.
4. Pre-shape and Bench Rest: Shape into a round, rest 20–30 minutes uncovered to build surface tension.
5. Final Shape: Tighten into final form (boule or batard), ensuring taut surface.
6. Proof: Proof seam-side up in a lined banneton or seam-side down in a bowl. At room temp: 2–4 hours. In fridge: 10–16 hours.
7. Check Readiness: Poke test should show slow rebound. Dough should feel airy but not fragile.
8. Bake: Score deeply, transfer to preheated Dutch oven, bake covered 20 min at 450°F, then uncovered 20–25 min until internal temp reaches 205–210°F.

Mini Case Study: From Flat Loaf to Perfect Crumb

Julia, an enthusiastic home baker in Portland, struggled for months with flat, dense sourdough. Her starter was active, her scales accurate, yet every loaf collapsed after baking. She documented each bake, noting variables like time, temperature, and appearance.

After reviewing her process, she realized two issues: First, she was leaving her dough in the banneton for 14 hours at room temperature—far beyond optimal. Second, she was using 80% hydration with all-purpose flour, making the dough too slack to hold shape.

She adjusted by reducing room-temperature proof to 3.5 hours and lowering hydration to 72%. She also began doing four sets of stretch and folds during bulk fermentation. On her next bake, the loaf rose evenly in the oven and held its height after cooling. The crumb was open and elastic, with no signs of collapse. Julia now bakes weekly with consistent success, attributing her breakthrough to understanding timing and dough strength.

Essential Sourdough Collapse Prevention Checklist

• ✅ Starter is ripe (peaks 4–6 hours after feeding, floats in water)
• ✅ Used stretch and folds or mechanical mixing to build gluten
• ✅ Hydration matches flour type (≤75% for AP flour)
• ✅ Bulk fermentation ended when dough increased by ~70%, not based solely on time
• ✅ Final proof stopped before dough becomes overly puffy or jiggly
• ✅ Scored deeply and confidently with a sharp blade
• ✅ Baking vessel fully preheated with lid on for first phase
• ✅ Internal temperature reached at least 208°F before removing from oven

Frequently Asked Questions

Why did my sourdough rise in the oven but fall within minutes?

This is typically due to overproofing. The dough expanded rapidly during oven spring but lacked structural integrity to maintain the rise. The gas escaped, and the weakened gluten collapsed. Try shortening your final proof by 30–60 minutes.

Can I save a collapsed sourdough loaf?

Yes—texture and flavor are often still excellent. Slice and toast it, use it for breadcrumbs, or turn it into sourdough croutons or bread pudding. Collapse affects appearance more than edibility.

Does a weaker starter cause collapse?

Indirectly, yes. A sluggish starter leads to underfermentation, resulting in poor gas production and weak oven spring. But more commonly, a very active starter left too long causes overproofing. Balance is key: feed your starter 4–6 hours before use and ensure it doubles in volume.

Conclusion: Build Confidence Through Consistency

A collapsed sourdough loaf isn’t a failure—it’s feedback. Each bake teaches you more about your flour, environment, and timing. The path to consistent, lofty loaves lies not in perfection but in observation and adjustment. Track your variables, respect fermentation windows, and prioritize dough strength over speed. With attention to detail and a willingness to learn from each outcome, you’ll develop the intuition that turns unpredictable results into repeatable success.

💬 What’s your biggest sourdough challenge? Share your experiences or ask questions in the comments—let’s grow better bread together.