High-Hydration 78% Open Crumb Sourdough with 400g Flour, 273g Autolyse & 30g Bassinage (1 Small Boule)
Open-crumb 78% formula for 400g flour (792g 1 small boule) staging 30g bassinage water and 80g levain.
Scaling a 400g sourdough build to 78% with 80g 1:1:1 levain means an unadjusted 312g water pour drifts to 80% (+2% excess) from 40g hidden liquid and 40g fermented flour. Weighing 303g main water (-9g offset) plus 8.8g sea salt locks True Total Hydration at 77.95% (target 78%) across a 792g loaf.
- Strict True Hydration Water
- 303gLocks True Total Hydration at 77.95% (target 78%, -9g)
- Unadjusted Apparent Water
- 312gPushes True Hydration to 80% (+2% surge)
- 20% Active Starter & Salt
- 80g / 8.8g40g hidden flour + 40g hidden water
- Stickiness & Rheology
- 4 / 5 StarsArtisan Level (High extensibility)
Starter Inoculation & Water Deduction Table Around 400g Flour @ 78%
Exact autolyse (273g) and bassinage (30g) water calibration around 400g flour at 78% hydration.
| Batch & Seed Spec | Flour Breakdown | Levain Split | Corrected Water (78% Ref) | Salt & Dough Mass | Apparent vs Locked |
|---|---|---|---|---|---|
| 350g @ 76% (15% Seed) Compact Mix (-50g) | 350g + 27g = 377g (78%/400g ref) | 53g (27gF/26gW @ 100%) | 261g W (vs 266g app @ R1) | 7.5g salt (664g dough) | 77.5% drift → 76.13% (76% goal) |
| 400g @ 76% (18% Seed) Conservative Pour | 400g + 40g = 440g (78%/400g ref) | 72g (40gF/32gW @ 80%) | 302g W (vs 304g app @ R2) | 8.8g salt (774g dough) | 76.4% drift → 75.91% (76% goal) |
| 400g @ 78% (20% Seed) [Locked Benchmark] | 400g + 40g = 440g (78%/400g ref) | 80g (40gF/40gW @ 100%) | 303g W (vs 312g app @ R3) | 8.8g salt (783g dough) | 80.0% drift → 77.95% (78% goal) |
| 400g @ 80% (22% Seed) Open-Crumb Push | 400g + 44g = 444g (78%/400g ref) | 88g (44gF/44gW @ 100%) | 311g W (vs 320g app @ R4) | 8.9g salt (799g dough) | 82.0% drift → 79.95% (80% goal) |
| 450g @ 80% (25% Seed) Expanded Loaf (+50g) | 450g + 50g = 500g (78%/400g ref) | 113g (50gF/63gW @ 125%) | 337g W (vs 360g app @ R5) | 10.0g salt (900g dough) | 84.6% drift → 80.0% (80% goal) |
Dynamic Stoichiometric Workbench (303g)
Test custom loaf weights or alternative fermentation schedules directly against the 312g benchmark above.
Wet Viscosity Control at 78% Hydration (400g Flour / 303g Corrected Water)
Precision scaling for a 792g (1 Small Boule) bake starts with 440g system flour (400g main + 40g levain). Instead of pouring 312g water (80% actual), deducting 9g to 303g main water (273g + 30g) and 8.8g salt locks True Total Hydration at 77.95% (target 78%).
Capillary water binding across 440g total flour (400g + 40g) at 77.95% (78% target) leaves a 4/5 stickiness profile with high extensibility. Subtracting 9g water (303g vs 312g) and dosing 8.8g salt locks vertical oven spring in the 792g loaf.
Execution Schedule: 400g Flour, 303g Water & 80g Starter (77.95%)
- Autolyse Soak (273g W + 400g F): Hydrate 400g flour with 273g water (90% of 303g) for 45 min before adding 80g starter.
- Levain & Bassinage (80g starter + 8.8g salt + 30g W): Dimple 80g ripe levain (40gF/40gW) and 8.8g salt with 30g water to hit 77.95% (78%).
- Coil Fold Cadence (4/5 Tack, 792g Dough): Space 4 wet-hand folds 30 min apart to align the 440g flour network (high stretch).
- Bulk Cutoff & 450°F Bake (1 Small Boule): Ferment at 75°F to +50% aliquot rise, cold-retard 14 hrs at 38°F, and bake covered 20 min + uncovered 22 min.
Key Baker's Math Questions (Strict True Hydration Water: 303g)
How much water should I hold back for bassinage in a 400g flour / 78% dough?
Out of 303g corrected main water for 400g flour at 78%, mix 273g (90%) during the 45-minute autolyse and trickle in 30g (10%) with 80g starter and 8.8g salt.
How much water do I need for 400g of flour at 78% hydration?
Multiplying 400g by 78% gives 312g apparent water, which drifts to 80% (+2%) with 80g starter. Weighing 303g main water (-9g cut) locks True Total Hydration at 77.95% (target 78%).
How many loaves does 400g flour at 78% hydration (792g) make?
A 400g flour formula with 303g water, 80g starter, and 8.8g salt produces 792g total dough—ideal as 1 Small Boule at 77.95% (78%).