Temperature × recipe
Hokkaido Milk Bread (Sourdough) at 63–67°F
Adjusted timing: 4.8h bulk + 5.7h proof (multiplier 1.90×).
- Baseline bulk (76°F)
- 2.5h
- Adjusted bulk
- 4.8h
- Baseline proof
- 3h
- Adjusted proof
- 5.7h
- Multiplier
- 1.90×
- Activity
- moderate
- Target hydration
- 72%
- Bake temp
- 350°F
Why the timing shifts
Cool kitchen — spring/fall without heating, air-conditioned summer. Ferment 1.5× longer than baseline. Good flavor development territory. Dough develops more complex sour notes. Manageable schedule. Extend bulk and proof by 50% vs recipe defaults.
Technique for Hokkaido Milk Bread (Sourdough)
Make tangzhong: 25g bread flour + 125g water, heat in pan stirring to 65°C until thick paste. Cool. Combine tangzhong with other dough ingredients + levain. Knead 10 min. 2.5h bulk. Divide into 3 pieces, roll each into rectangle, fold thirds, roll into coil. Place coils side-by-side in oiled loaf pan. Proof 3h until risen 1 inch above pan. Bake 350°F for 30-35 min until golden and internal 190°F.
Calculator pre-set to these values
- Multiplier at 65°F
- 1.9×
- Adjusted bulk ferment
- 4.8 h
- Adjusted final proof
- 5.7 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.