Temperature × recipe
Pain au Levain at 68–72°F
Adjusted timing: 6.1h bulk + 16.2h proof (multiplier 1.35×).
- Baseline bulk (76°F)
- 4.5h
- Adjusted bulk
- 6.1h
- Baseline proof
- 12h
- Adjusted proof
- 16.2h
- Multiplier
- 1.35×
- Activity
- moderate
- Target hydration
- 72%
- Bake temp
- 480°F
Why the timing shifts
Most home kitchens — typical year-round room temperature. Ferment slightly longer than 76°F baseline. Recipe times generally work as written with minor extensions (+20%). Good balance of schedule manageability and flavor development. Most Hamelman and Tartine formulas are written assuming this range.
Technique for Pain au Levain
Autolyse 60 min. Add levain (100% hydration, 15-20% of flour weight) and salt. 3 sets of stretch-and-folds. Total bulk 4.5h at 76°F. Shape tight boule, cold retard 12h. Bake in 480°F dutch oven: 22 min lid on, 22 min lid off.
Calculator pre-set to these values
- Multiplier at 70°F
- 1.35×
- Adjusted bulk ferment
- 6.1 h
- Adjusted final proof
- 16.2 h
How the math works
Multipliers are piecewise-linear interpolations between reference points measured by Myhrvold et al. in Modernist Bread vol 3. 76°F is the baseline (1.0×); every 10°F drop roughly doubles fermentation time, and every 10°F rise roughly halves it.