What this is about
Bulk fermentation is the first rise of the whole, undivided dough: it ripens in the bowl, and the yeasts make gas while the bacteria make acid. It decides how airy your bread will be later, and you read the ripeness from the dough, not from the clock.
How to do it
Bulk fermentation has been running since 16:30, when you worked in the levain and salt. All times apply to 24 °C at the dough.
- 16:30 to 18:30, stretch and fold: You have stretched and folded the dough four times (17:00, 17:30, 18:00, and 18:30). Between rounds the bowl stays covered so the dough does not form a skin.
- 18:30, after the last fold: Measure the dough temperature in the middle; it should be 24 °C. Then mark the height of the dough on the bowl, for example with a strip of tape or a rubber band. A straight bowl with vertical walls shows the growth best. Cover it and do not touch the dough until 20:30. It now rests for two hours.
- 20:30, check: Look at the mark from the side and read the height at the edge, because in the middle the dough domes higher. The dough should stand about one and a half times as high as at 18:30. Then do the jiggle test: shake the bowl gently and tilt it a little. A ripe dough pulls away from the edge and wobbles like pudding.
- If the signs are there, go on to the preshape. If they are missing, wait and check again every 30 minutes. Do not go by the clock; go by the dough.
- If your kitchen is warm and the signs are there before 20:30, preshape earlier.
How you know it is right
The finished dough stands about one and a half times as high as after the last fold. Its surface is domed, and bubbles sit at the edge and on top. When you tilt the bowl, it pulls away from the edge, and when you shake it, it wobbles like pudding. It smells mildly of yogurt. All the signs count together; a single one is not enough.
If it was too early, it has hardly grown and is dense, the surface is flat, and there are hardly any bubbles. Keep waiting then. If it was too late, it has collapsed, is very soft and sticky, and smells sharply sour. In that case preshape it right away so it does not get even softer.
The four hours are a guide value for 24 °C at the dough and 20 percent levain, not an order. If the dough is below 24 °C at 18:30, it grows more slowly. Then it is not ready until after 20:30, and you push everything after it back, including shaping and the fridge. If the dough sits in a warm kitchen, it goes faster, and you preshape earlier. The dough keeps fermenting after the preshape, so in the bowl it must not rise by more than one and a half times.
Rules to remember
- Set the mark only after the last fold, at 18:30.
- The dough is ready when it stands one and a half times as high, is domed, has bubbles, and wobbles like pudding, not when the clock says 20:30.
- It is better to wait another half hour than to preshape too early.
In the Pro edition: the volume target against dough temperature, the temperature window of yeasts and bacteria, the test in the aliquot jar, the overnight bulk, the rescue of over- and under-fermented doughs, and what happens in the dough with gas and structure.