Sourdough Bulk Fermentation Time at 75 Degrees (75°F / 24°C) with 30% Starter (+48.8% Rise)
LAB 6.1:1 organic acid balance and 3.3–4.1 hr bulk schedule for 75°F (23.9°C) doughs inoculated at 30%.
Under 75°F (23.9°C) thermal kinetics (Q10=1x) and 30% starter (150g/500g), bulk spans 3.3–4.1 hours with a 6.1:1 lactic-to-acetic profile. Terminate fermentation at +48.8% true volumetric expansion (+37.3% vertical height rise in a sloped bowl to 5.49 cm), preventing the +65.3% volume explosion of a 2x vertical climb.
- Estimated Bulk Time
- 3.3–4.1 hrsAt 75°F (23.9°C) with 30% starter (Q10=1x)
- Target Aliquot Volume Rise
- +48.8%Capped volumetric cutoff (<44.4°F dormancy)
- Sloped Bowl Height Target
- 5.49 cm+37.3% vertical climb from 4.0 cm
- 2x Height Trap Warning
- +65.3% VolCoil fold every 26m (LAB 6.1:1)
Conical Height vs. Aliquot Volume Matrix Centered on 75°F / 30% Starter
5-point neighborhood comparison around 75°F (23.9°C) and 30% starter (150g/500g flour), showing window hours, conical height rise %, straight-wall volume rise %, and 26-min coil fold intervals.
| Temp & Levain Seed (Around 75°F / 30%) | Fermentation Window | 9" Conical Height Rise | Straight-Wall Volume Rise | Coil Fold Cadence |
|---|---|---|---|---|
| 73°F (22.8°C) @ 28% (140g) Cooler / Lower Seed | 4–5.1 hrs (240–306m) | +44.3% height (4.0 → 5.77 cm) | +58.8% vol (2x trap: +80.1%) | Every 29 min (Row 1) |
| 75°F (23.9°C) @ 28% (140g) Baseline Temp / Lower Seed | 3.5–4.3 hrs (210–258m) | +37.4% height (4.0 → 5.5 cm) | +49% vol (2x trap: +65.6%) | Every 27 min (Row 2) |
| 75°F (23.9°C) @ 30% (150g) [Current Target] | 3.3–4.1 hrs (198–246m) | +37.3% height (4.0 → 5.49 cm) | +48.8% vol (2x trap: +65.3%) | Every 26 min (Row 3) |
| 75°F (23.9°C) @ 33% (165g) Baseline Temp / Higher Seed | 3.1–3.8 hrs (186–228m) | +37% height (4.0 → 5.48 cm) | +48.4% vol (2x trap: +64.7%) | Every 25 min (Row 4) |
| 77°F (25°C) @ 33% (165g) Warmer / Higher Seed | 2.6–3.3 hrs (156–198m) | +32.3% height (4.0 → 5.29 cm) | +41.9% vol (2x trap: +55.3%) | Every 23 min (Row 5) |
Interactive Bulk Fermentation Temp × Inoculation Calculator
Compare your exact mixing bowl dimensions, flour protein percentage, or discard weight in real time.
When to Stop Bulk Fermentation at 75 Degrees (75°F / 24°C): Target +48.8% Rise
Alveograph tenacity-to-extensibility (P/L) ratios shift rapidly at 75°F (23.9°C) when seeded with 30% levain (150g/500g). Across 3.3–4.1 hours (Q10=1x), each 26-minute coil fold restores elastic recovery until the +37.3% sloped-bowl mark (5.49 cm, +48.8% volume) signals immediate shaping.
According to Henry's Law of gas solubility, chilling a 75°F (23.9°C) dough mass below 44.4°F increases aqueous CO2 absorption into the dough liquor while 30% levain yeast slows down. Shaping at 5.49 cm (+37.3% conical climb, +48.8% volume) after 3.3–4.1 hrs preserves spring without hitting the +65.3% trap.
4-Stage Bench & Cold-Retard Protocol for 75°F Dough at 30% Starter
- Formula Seeding (150g Starter / 75°F): Fold 30% active starter into your 500g main flour dough at 75°F (23.9°C) (Q10 factor 1x).
- Interval Folding (26 Mins Apart): Apply wet-hand coil folds every 26 minutes to reinforce disulfide cross-links during the 3.3–4.1 hr bulk.
- Conical Frustum Inspection (5.49 cm): Verify a +37.3% vertical rise (4.0 → 5.49 cm, equal to +48.8% volume) rather than risking a +65.3% 2x height explosion.
- Cold Proofing Arrest (<44.4°F): Pre-shape, rest 20 min, final-shape, and load into a 38°F fridge so fermentation tapers off below 44.4°F.
Frequently Asked Questions for This Bulk Fermentation Temp × Inoculation Spec
Why is the recommended rise capped at +48.8% for 75°F and 30% starter?
Capping bench expansion at +48.8% true volumetric expansion (+37.3% vertical height rise in a sloped bowl) preserves glutenin elasticity against protease clipping (Q10=1x) and avoids a +65.3% volume explosion.
Can I cold-retard a 75°F (30% starter) dough for 16 hours after bulk?
Yes—provided you terminate bench fermentation at +48.8% true volumetric expansion (5.49 cm sloped height) after 3.3–4.1 hrs so thermal carryover to 44.4°F does not overproof the gluten.
What is the Q10 metabolic speed factor at 75°F (23.9°C)?
At 75°F (23.9°C), sourdough yeast and LAB operate at a 1x Q10 velocity relative to 75°F, yielding a 6.1:1 lactic-to-acetic acid ratio over 3.3–4.1 hours at 30% starter.