Temperature × recipe
Pain au Levain at 83–87°F
Adjusted timing: 2.5h bulk + 6.7h proof (multiplier 0.56×).
- Baseline bulk (76°F)
- 4.5h
- Adjusted bulk
- 2.5h
- Baseline proof
- 12h
- Adjusted proof
- 6.7h
- Multiplier
- 0.56×
- Activity
- hyperactive
- Target hydration
- 72%
- Bake temp
- 480°F
Why the timing shifts
Hot kitchen — summer without AC, near-window light. Ferment nearly 2× faster than baseline. Not ideal — fermentation outpaces gluten development, leading to over-acidic flavor and collapsed structure. If unavoidable, use very low levain (10-12%), minimal bulk (2h max), and get dough into cold retard ASAP. Consider reducing bulk temperature by moving dough to cooler location (basement, refrigerator brief intervals).
Technique for Pain au Levain
Autolyse 60 min. Add levain (100% hydration, 15-20% of flour weight) and salt. 3 sets of stretch-and-folds. Total bulk 4.5h at 76°F. Shape tight boule, cold retard 12h. Bake in 480°F dutch oven: 22 min lid on, 22 min lid off.
Calculator pre-set to these values
- Multiplier at 85°F
- 0.56×
- Adjusted bulk ferment
- 2.5 h
- Adjusted final proof
- 6.7 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.