Temperature × recipe

100% Whole Wheat Pan Loaf at 8895°F

Adjusted timing: 1.6h bulk + 3.1h proof (multiplier 0.39×).

Baseline bulk (76°F)
4h
Adjusted bulk
1.6h
Baseline proof
8h
Adjusted proof
3.1h
Multiplier
0.39×
Activity
extreme-mold-risk
Target hydration
80%
Bake temp
425°F

Why the timing shifts

Very hot — avoid. Mold risk rises sharply above 85°F. Fermentation outpaces structural development. Levain becomes unbalanced toward lactic acid producers, creating cloying sour flavor. Only use briefly for refreshing starters or if absolutely unavoidable. Move dough to cooler location, or skip this bake and wait for cooler conditions. If baking must happen, reduce levain to 8%, bulk 90 min max, get into refrigerator immediately after shaping.

Technique for 100% Whole Wheat Pan Loaf

Long autolyse (90 min) with 100% of the water at 80°F. Add levain and salt, mix until fully incorporated. 4 stretch-and-folds in 2h. Total bulk 4h. Shape into log, place seam-side down in oiled 9x5 loaf pan. Cold retard overnight. Bake at 425°F for 35-40 min until internal 200°F.

Calculator pre-set to these values

Multiplier at 92°F
0.39×
Adjusted bulk ferment
1.6 h
Adjusted final proof
3.1 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); WSU Bread Lab — Whole wheat sourdough research.