Temperature × recipe

Sourdough Bagel at 3640°F

Adjusted timing: 2.9h bulk + 34.8h proof (multiplier 2.90×).

Baseline bulk (76°F)
1h
Adjusted bulk
2.9h
Baseline proof
12h
Adjusted proof
34.8h
Multiplier
2.90×
Activity
dormant
Target hydration
55%
Bake temp
500°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 Bagel

Mix dough (stand mixer recommended due to stiffness). Short 1h bulk. Divide into 100g pieces, shape into rings. Place on parchment, cold retard 12-24h. Bring 4L water + 2 tbsp malt syrup + 1 tsp baking soda to gentle boil. Drop bagels 30 sec per side. Transfer to sesame/poppy/everything seeds if desired. Bake on preheated baking sheet at 500°F with steam for 18 min until deep golden.

Calculator pre-set to these values

Multiplier at 38°F
2.9×
Adjusted bulk ferment
2.9 h
Adjusted final proof
34.8 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); Peter Reinhart — The Bread Baker's Apprentice, Bagel formula.