Sourdough Bulk Fermentation Time at 72 Degrees (72°F / 22°C) with 10% Starter (+66.6% Rise)
Q10=0.8x metabolic curve for 50g starter per 500g flour at 72°F (22.2°C): stop at 5.99 cm bowl height (+66.6% aliquot rise).
Fermenting a 72°F (22.2°C) dough inoculated at 10% (50g active culture/500g flour) requires 9.2 to 11.8 hours with 37-minute coil folds. Shape at +66.6% true volumetric expansion (+49.7% vertical height rise in a sloped bowl from 4.0 cm to 5.99 cm) to avoid the +92.1% volume explosion of a 2x height trap.
- Estimated Bulk Time
- 9.2–11.8 hrsAt 72°F (22.2°C) with 10% starter (Q10=0.8x)
- Target Aliquot Volume Rise
- +66.6%Capped volumetric cutoff (<44.6°F dormancy)
- Sloped Bowl Height Target
- 5.99 cm+49.7% vertical climb from 4.0 cm
- 2x Height Trap Warning
- +92.1% VolCoil fold every 37m (LAB 4.7:1)
2D Thermal & Inoculation Sensitivity Table for 72°F (22.2°C) @ 10% Levain
5-point neighborhood comparison around 72°F (22.2°C) and 10% starter (50g/500g flour), showing window hours, conical height rise %, straight-wall volume rise %, and 37-min coil fold intervals.
| Temp & Levain Seed (Around 72°F / 10%) | Fermentation Window | 9" Conical Height Rise | Straight-Wall Volume Rise | Coil Fold Cadence |
|---|---|---|---|---|
| 70°F (21.1°C) @ 8% (40g) Cooler / Lower Seed | 12.9–15.9 hrs (774–954m) | +55.2% height (4.0 → 6.21 cm) | +74.7% vol (2x trap: +104.8%) | Every 40 min (Row 1) |
| 72°F (22.2°C) @ 8% (40g) Baseline Temp / Lower Seed | 10.9–13.9 hrs (654–834m) | +50% height (4.0 → 6 cm) | +67% vol (2x trap: +92.7%) | Every 37 min (Row 2) |
| 72°F (22.2°C) @ 10% (50g) [Current Target] | 9.2–11.8 hrs (552–708m) | +49.7% height (4.0 → 5.99 cm) | +66.6% vol (2x trap: +92.1%) | Every 37 min (Row 3) |
| 72°F (22.2°C) @ 13% (65g) Baseline Temp / Higher Seed | 7.6–9.7 hrs (456–582m) | +49.4% height (4.0 → 5.98 cm) | +66.1% vol (2x trap: +91.3%) | Every 36 min (Row 4) |
| 74°F (23.3°C) @ 13% (65g) Warmer / Higher Seed | 6.7–8.3 hrs (402–498m) | +42.4% height (4.0 → 5.7 cm) | +56% vol (2x trap: +75.9%) | Every 33 min (Row 5) |
Live Parameter Solver for Sourdough Bulk Fermentation Time at 72 Deg
Dial in custom baker's percentages and export your adjusted 9.2–11.8 hrs formula for bake day.
When to Stop Bulk Fermentation at 72 Degrees (72°F / 22°C): Target +66.6% Rise
By integrating the conical frustum volume integral V(z) = ∫ π r(z)² dz across a 14 cm base and 24 cm rim, a +66.6% volumetric expansion at 72°F (22.2°C) and 10% inoculation lifts dough height by only +49.7% (from 4.0 cm to 5.99 cm). Waiting for vertical height to double during the 9.2–11.8 hr window creates a +92.1% volume explosion.
Newtonian thermal inertia dictates that a 900g loaf transferred from 72°F (22.2°C) into a 38°F (3.3°C) refrigerator continues fermenting until its core crosses 44.6°F. With 10% starter (Q10=0.8x), cutting off bench bulk at +66.6% volume (5.99 cm / +49.7% height after 9.2–11.8 hrs) prevents cold-retard overproofing.
Managing a 72°F (22.2°C) / 10% Inoculation Sourdough Schedule
- Seed & Thermal Check (72°F / 22.2°C): Verify dough core reads 72°F after incorporating 50g active levain (10% baker's math) for a 4.7:1 LAB balance.
- Aliquot & Sloped Vessel Setup: Place 40g dough in a straight cylinder (mark +66.6%) and set a ruler at 5.99 cm (+49.7% climb) on your 24 cm sloped bowl.
- Gluten Alignment (37-Min Intervals): Perform gentle folds every 37 minutes without degassing; stop folding 90 minutes before hour 9.2.
- Bench Preshape & 38°F Retard: Dump onto the bench between 9.2 and 11.8 hours at +66.6% rise, tension-roll, and refrigerate immediately until core drops past 44.6°F.
Cereal Chemistry & Bench Execution FAQs
How many grams of starter is 10% inoculation for a 500g flour loaf at 72°F?
A 10% inoculation on 500g main flour equals 50g of active 100% hydration starter (25g flour + 25g water), fermenting in 9.2–11.8 hours at 72°F.
What is the Q10 metabolic speed factor at 72°F (22.2°C)?
At 72°F (22.2°C), sourdough yeast and LAB operate at a 0.8x Q10 velocity relative to 75°F, yielding a 4.7:1 lactic-to-acetic acid ratio over 9.2–11.8 hours at 10% starter.
What happens if my 72°F kitchen warms up by 2°F during a 10% starter bulk?
A +2°F rise to 74°F accelerates Q10 kinetics above 0.8x and shortens the 9.2–11.8 hr window, so monitor the 5.99 cm (+66.6% volume) mark closely.