Temperature × recipe

Sourdough Challah at 3640°F

Adjusted timing: 5.8h bulk + 8.7h proof (multiplier 2.90×).

Baseline bulk (76°F)
2h
Adjusted bulk
5.8h
Baseline proof
3h
Adjusted proof
8.7h
Multiplier
2.90×
Activity
dormant
Target hydration
55%
Bake temp
350°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 Sourdough Challah

Stand mixer: combine flour, eggs, water, oil, sugar, levain, salt. Knead 8 min on medium. 2h bulk at 76°F with 2 folds. Divide into strands (3/4/6), braid. Proof 3h at 76°F. Egg wash, optionally top with sesame or poppy. Bake 350°F for 30 min until internal 190°F.

Calculator pre-set to these values

Multiplier at 38°F
2.9×
Adjusted bulk ferment
5.8 h
Adjusted final proof
8.7 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); King Arthur Baking — Sourdough Challah + Jewish tradition.