Temperature × recipe
Pain au Levain at 36–40°F
Adjusted timing: 13.0h bulk + 34.8h proof (multiplier 2.90×).
- Baseline bulk (76°F)
- 4.5h
- Adjusted bulk
- 13.0h
- Baseline proof
- 12h
- Adjusted proof
- 34.8h
- Multiplier
- 2.90×
- Activity
- dormant
- Target hydration
- 72%
- Bake temp
- 480°F
Why the timing shifts
Refrigerator territory — used for overnight retard during proofing or bulk slowdown. 12-16 hours at this temperature is equivalent to 1-1.5 hours at 76°F baseline. Essential for flavor development in artisan sourdough. Cold retard improves shape retention, enables flexible scheduling, and develops deeper tangy flavors. Place dough in floured banneton, cover, refrigerate at this temperature.
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 38°F
- 2.9×
- Adjusted bulk ferment
- 13.1 h
- Adjusted final proof
- 34.8 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.