Sourdough, explained properly.
In-depth guides on fermentation, hydration, starters, scoring, and the things that actually go wrong. Every number comes from the same fermentation model as the calculator.
Bulk fermentation by temperature: a baker's guide
Sourdough bulk fermentation time by dough temperature: about 5 h at 24°C (75°F), 9 h at 18°C (64°F). A table, the 2.2× rule, and the done signs.
Read →Why is my sourdough gummy inside (and how to fix it)
Gummy sourdough is usually cut too warm, underbaked (aim for 96°C/205°F inside) or proofed wrong for the dough temperature. How to tell which.
Read →How to revive a forgotten sourdough starter
Starter forgotten in the fridge? Pour off the hooch, feed 1:1:1, then 1:2:2 at room temperature, and bake once it doubles on schedule twice.
Read →Sourdough hydration explained: 65%, 75%, 85%, 100%
Sourdough hydration is water as a percentage of flour: 75% is 75 g water per 100 g flour. How 65%, 75%, 85% and 100% doughs behave, by flour.
Read →Cold retard vs same-day bake: when to use each
Cold retard or same-day sourdough? 12 hours at 4°C (39°F) gives more flavor, easy scoring and a morning bake; same-day is milder and faster.
Read →The float test: when is your starter actually ready?
A starter that floats is holding gas, not necessarily at peak. Why the float test fails on cold, wet and rye starters, and what to watch instead.
Read →Desired dough temperature (DDT): water temperature formula
Water = (target × 3) − flour − room − friction. How to use the DDT formula, friction by mixing method, and worked examples in °C and °F.
Read →How to fix dense sourdough (12 causes diagnosed)
Dense sourdough usually means underproofed bulk, cold dough or a weak starter. Check those three first, then work through nine more causes and fixes.
Read →Starter feeding ratios: 1:1:1 vs 1:2:2 vs 1:5:5
At 22°C a 1:1:1 feed peaks in about 4 hours, 1:2:2 in 5½ and 1:5:5 in 8 (model estimates). Which starter feeding ratio fits your bake schedule.
Read →Stretch and fold: how many, when, and why
Most sourdough needs 4 sets of stretch and folds, 30 minutes apart, inside the first half of bulk. How to scale folds to hydration and dough temperature.
Read →Scoring sourdough: ear, bloom, and the basic patterns
For an ear, score cold dough with a sharp blade at 20–30°, about 6 mm deep. Angles, depths and patterns for sourdough, and why loaves don't bloom.
Read →Autolyse vs fermentolyse: the math behind both
Autolyse rests flour and water before the starter goes in; fermentolyse adds it at once. When to use each, how long to rest, and how it shifts bulk.
Read →Whole wheat sourdough: hydration, timing, and protein
Whole wheat sourdough needs more water (78–87%), a bulk about 15–30% shorter and an earlier shape. Hydration table, timing and a 50% formula.
Read →Rye sourdough: hydration, acidity and bake rules
Rye needs more levain (30–40% prefermented flour), 80–95% hydration, a warm ferment, a long bake to 98–99°C and a full day before slicing.
Read →Winter sourdough: surviving a cold kitchen
A 16°C kitchen ferments at under half the speed of 24°C. Warm water, warm spots, a tighter starter feed and bulk times for a cold kitchen.
Read →Sourdough in hot weather: bulk timing for a warm kitchen
In a 28°C kitchen bulk can drop to about 3½ hours. Cool the water, cut the levain, shape at about 50% rise and retard overnight. Times and tables.
Read →Sourdough starter from scratch: 7-day plan
Make a sourdough starter in 7 days with whole grain flour, water and a jar. Day-by-day feeds, what each stage looks like, and when it's ready to bake.
Read →Sourdough troubleshooting: 24 problems diagnosed
24 sourdough problems with cause and fix: starter won't rise, soupy dough, slow bulk, no oven spring, pale crust, gummy or dense crumb, too sour.
Read →Dutch oven vs baking stone: which crust wins?
A Dutch oven usually gives a thinner, glossier, more blistered crust; a stone wins for big batards and several loaves at once. Times and temps for both.
Read →Banneton care: seasoning, cleaning, and choosing one
Season a new banneton with rice flour, dry it upside down after every bake, never soak it. Plus which material and size to buy for your dough.
Read →Sourdough without a Dutch oven: 3 working methods
No Dutch oven? Bake on a steel or stone with a steam tray, or cover the loaf with a stainless bowl or deep roasting pan. Safe steps, times and temps.
Read →Sourdough starter not doubling? Check the time and your temperature first
A starter that rises but won't double may be cold or checked too soon. Model peak times by ratio and temperature, what a peak looks like, what else to check.
Read →How much starter in sourdough: what the percentage means and what it changes
How much starter to use in sourdough: grams for 500 g of flour, model bulk times at 20–24°C (68–75°F) by starter %, and the hidden hydration.
Read →Overnight bulk fermentation for sourdough: how much starter for your kitchen temperature
How much starter for an overnight sourdough bulk: the model's starter % for 8-, 10- and 12-hour nights by kitchen temperature, and the morning check.
Read →How long to proof sourdough after shaping at room temperature
How long to proof sourdough after shaping: about 3 h at 22°C (72°F) by the model, a table for 18–26°C, when to start the poke test and how to read it.
Read →Convert a yeast recipe to sourdough: starter, water and bulk time
Convert a lean yeast bread recipe to sourdough: how much levain, how much water to hold back, and the model's bulk and proof times at 20–24°C (68–75°F).
Read →Baking sourdough in a fan or convection oven: fan off, covered
Why a convection fan dries and browns a sourdough crust, how to find the fan-off setting, and what to change if your oven only bakes with the fan.
Read →Plan your next bake
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