Temperature × recipe

Pain au Levain at 5862°F

Adjusted timing: 11.5h bulk + 30.6h proof (multiplier 2.55×).

Baseline bulk (76°F)
4.5h
Adjusted bulk
11.5h
Baseline proof
12h
Adjusted proof
30.6h
Multiplier
2.55×
Activity
sluggish
Target hydration
72%
Bake temp
480°F

Why the timing shifts

Cold kitchen territory — cellars, garages, unheated rooms. Ferment time is 2.5× longer than baseline 76°F. Excellent for flavor development when you have the patience. If your kitchen runs this cold naturally, either move dough to a warmer spot or extend bulk and proof times dramatically. Consider using 20-25% levain instead of 15-20% to compensate for slow activity.

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 60°F
2.55×
Adjusted bulk ferment
11.5 h
Adjusted final proof
30.6 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.