Dough Dough Guides
Sourdough leaves clues. A dense, gummy crumb, a loaf that spread out flat, no rise at all — each one is telling you exactly what went wrong, and almost always it comes down to fermentation or temperature. Here's how to read your loaf and put it right next time.
By Richard — I bake fresh sourdough every day for our Airbnb guests, and I've made every single one of these mistakes myself. This is how I diagnose a loaf from the loaf itself.
Start here: three culprits behind almost everything
Before the symptom-by-symptom list, know that the vast majority of sourdough problems trace back to one of these three things:
- Under-fermented dough (the most common by far) — not enough time or warmth during the bulk rise. Gives you dense, tight, gummy loaves, often with a burst side seam.
- Over-fermented dough — left too long or too warm. Gives you a flat, slack loaf that spreads, with little oven spring and a sharper, sourer taste.
- A sluggish starter — it wasn't bubbly and at its peak when you mixed, so the dough never had the lift it needed.
Get fermentation and a lively starter right and almost everything else falls into place. Now, the specifics.
Dense, heavy, tight crumb
The classic beginner loaf. Nearly always under-fermented: the dough was shaped before it had risen enough. Give the bulk rise more time and warmth — look for the dough to grow by about 30–50%, dome up and feel airy before you shape (see my guide on knowing when bulk is done). A weak starter or a too-cool kitchen are the usual causes.
Gummy, sticky crumb — even once it's cooled
Three possible causes, in order of likelihood:
- Under-baked. The inside hadn't finished. I bake every loaf to an internal temperature of ~98°C — a probe thermometer takes the guesswork out completely.
- Sliced too soon. A loaf keeps cooking as it cools; cut it hot and the crumb pastes together. Wait at least an hour.
- Under-fermented. See above — a tight, under-proofed crumb often reads as gummy.
Flat loaf that spread sideways
Usually over-fermented — the dough lost its structure and couldn't hold its shape, so it pancaked in the oven. Shorten the bulk or keep the dough cooler next time. The other cause is slack shaping: not enough surface tension. A tight, well-shaped loaf holds tall — see my shaping guide.
No oven spring, no "ear"
- Oven not hot enough. Preheat your Dutch oven until it's screaming hot — that first blast of heat is what drives the spring.
- Under- or over-proofed. Both kill spring. Aim for the sweet spot.
- A timid score. One deep, confident cut gives the loaf a place to burst open — see scoring.
It barely rose during bulk at all
This points straight at the starter or the temperature. Your starter may not have been active when you mixed, or the dough was simply too cold to ferment. Make sure your starter is bubbly and passes the float test before you use it, and keep your dough somewhere warm (24–26°C is ideal). If the starter itself seems off, work through my starter troubleshooting guide.
Too sour
A long or warm ferment, a long cold proof, or a high proportion of wholemeal all push the flavour more sour. For a milder loaf, shorten the bulk a little, keep things cooler, and use your starter at its peak rather than when it's hungry.
Not sour enough
Honestly, often a good thing — but if you want more tang, give it a longer, cooler ferment and a longer cold proof in the fridge. A more mature starter and a touch more wholemeal add depth too.
Pale crust that won't brown
The oven wasn't hot enough, there wasn't enough steam in the first half of the bake (the lid-on stage traps it), or the dough was over-proofed so the sugars that brown the crust were already used up. Bake hotter, keep the lid on for the first 20 minutes, and check your fermentation.
The two-minute diagnosis
When a loaf disappoints, look at two things:
- The crumb. Tight and dense = under-fermented. Wild, irregular caverns with a flat shape = over-fermented. Even, open and springy = you nailed it.
- A gummy line along the base usually means under-baked or sliced too warm — bake longer (to 98°C) and cool fully.
Most "it didn't work" loaves start with a sluggish culture. Ours is live, organic and active in 2 hours — a reliable, lively start every time.
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