Temperature × recipe

Pain au Levain at 7377°F

Adjusted timing: 4.7h bulk + 12.6h proof (multiplier 1.05×).

Baseline bulk (76°F)
4.5h
Adjusted bulk
4.7h
Baseline proof
12h
Adjusted proof
12.6h
Multiplier
1.05×
Activity
active
Target hydration
72%
Bake temp
480°F

Why the timing shifts

BASELINE — the reference temperature for all fermentation times in this system. Warm kitchen, proofing box, summer AC setting. 76°F (24.4°C) is the classical bakery target. If you control dough temperature via dough desired temperature (DDT) calculations, aim for this range. All published recipe times assume this temperature unless otherwise noted.

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 75°F
1.05×
Adjusted bulk ferment
4.7 h
Adjusted final proof
12.6 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.

Sources: Myhrvold, Modernist Bread vol 3 (temperature multipliers); Hamelman — Bread 3rd ed., Pain au Levain formula.