Field manual · Fermentation
Bulk fermentation guide
Bulk is controlled by dough temperature and starter dose. Read volume and structure, not the clock alone.
Dough temperature model
Reference: dough at 24 °C with 20% starter (of flour weight) completes bulk in about 5 hours. Every 5 °C (9 °F) cooler roughly doubles the time. Target dough temperature after mixing is 24 °C–26 °C; adjust the water temperature to get there.
| Dough temp | Bulk at 10% | Bulk at 20% | Bulk at 30% | Target rise |
|---|---|---|---|---|
| 18 °C | 17 h 24 min | 11 h 30 min | 9 h 0 min | 75% |
| 20 °C | 13 h 12 min | 8 h 42 min | 6 h 48 min | 75% |
| 22 °C | 10 h 0 min | 6 h 36 min | 5 h 12 min | 64% |
| 24 °C | 7 h 36 min | 5 h 0 min | 3 h 54 min | 53% |
| 26 °C | 5 h 42 min | 3 h 48 min | 3 h 0 min | 41% |
| 28 °C | 4 h 24 min | 2 h 54 min | 2 h 18 min | 30% |
Estimates from a rule of thumb. Starter strength, flour and salt change the real time; use the target rise as the end point.
Hydration and bulk
- 65–70%: tight dough, rise is easy to read in a straight-sided container. Fewer folds needed.
- 72–78%: standard open-crumb range. Plan 4 sets of stretch-and-folds in the first third of bulk.
- 80%+: ferments slightly faster and spreads; stop bulk at the lower end of the target rise and use coil folds.
- Wholegrain flour absorbs more water and ferments faster through extra enzymes and nutrients — expect 10–20% shorter bulk.
Bulk & proof calculator
- Water
- 375 g
- Ripe starter
- 100 g
- Bulk fermentation
- 5 h 0 min
- Stretch-and-fold window
- First 2 h 0 min · 4 sets
- End bulk at
- +53% volume
- Final proof, room temp
- 1–3 h at 21–24 °C
- Or cold retard
- 12–24 h at 3–5 °C
Starter weight is ripe 100%-hydration levain as a percentage of total flour. Weigh in grams for precision.
Proofing timeline
| Stage | Conditions | Ready when |
|---|---|---|
| Bench rest | 20–30 min, covered | Pre-shaped round relaxes and spreads slightly. |
| Room-temp proof | 1–3 h at 21 °C–24 °C | Poke springs back slowly and leaves a slight dent. |
| Cold retard | 12–24 h at 3 °C–5 °C | Firm, domed, small surface blisters; score straight from the fridge. |
| Bake | Preheated to 250 °C, lid on 20 min | Internal 96 °C–98 °C and deep crust colour. |