Temperature × recipe

Miche (Poilâne-Style) at 6367°F

Adjusted timing: 9.5h bulk + 22.8h proof (multiplier 1.90×).

Baseline bulk (76°F)
5h
Adjusted bulk
9.5h
Baseline proof
12h
Adjusted proof
22.8h
Multiplier
1.90×
Activity
moderate
Target hydration
78%
Bake temp
480°F

Why the timing shifts

Cool kitchen — spring/fall without heating, air-conditioned summer. Ferment 1.5× longer than baseline. Good flavor development territory. Dough develops more complex sour notes. Manageable schedule. Extend bulk and proof by 50% vs recipe defaults.

Technique for Miche (Poilâne-Style)

Autolyse 60 min with all water at 80°F. Add levain, salt. 4 folds in 2h. Long bulk 5h at 76°F. Shape very tight boule, heavily flour banneton. Cold retard 12h. Bake in LARGE dutch oven (7-qt minimum) at 480°F: 30 min lid on, 30 min lid off, or until internal 210°F.

Calculator pre-set to these values

Multiplier at 65°F
1.9×
Adjusted bulk ferment
9.5 h
Adjusted final proof
22.8 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.

Sources: Myhrvold, Modernist Bread vol 3 (temperature multipliers); Lionel Poilâne — Pain Poilâne (miche) reference.