Fermentation timing

Sourdough Brioche — Timing by Kitchen Temperature

Baseline: 2h bulk + 2h proof at 76°F. Adjust for your kitchen below.

Temperature × time table

Kitchen tempMultiplierBulk (h)Proof (h)
62°F2.20×4.44.4
68°F1.58×3.23.2
72°F1.23×2.52.5
76°F1.00×2.02.0
80°F0.78×1.61.6
85°F0.56×1.11.1

Calculator pre-set to Sourdough Brioche

Multiplier at 76°F
1×
Adjusted bulk ferment
2 h
Adjusted final proof
2 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 et al., Modernist Bread vol 3 (temperature multipliers); Hamelman — Bread 3rd ed., Brioche formula adapted for sourdough.