Extreme 90% Hydration Sourdough (750g Flour): 601g Base + 67g Bassinage (2-Loaf Batch)
Ciabatta-style 90% formula on 750g flour (1585g batch) with 67g bassinage staging and -7g starter deduction.
Scaling a 750g sourdough build to 90% with 150g 1:1:1 levain means an unadjusted 675g water pour drifts to 90.9% (+0.9% excess) from 75g hidden liquid and 75g fermented flour. Weighing 668g main water (-7g offset) plus 16.5g sea salt locks True Total Hydration at 90.06% (target 90%) across a 1585g loaf.
- Strict True Hydration Water
- 668gLocks True Total Hydration at 90.06% (target 90%, -7g)
- Unadjusted Apparent Water
- 675gPushes True Hydration to 90.9% (+0.9% surge)
- 20% Active Starter & Salt
- 150g / 16.5g75g hidden flour + 75g hidden water
- Stickiness & Rheology
- 5 / 5 StarsExtreme / Wet Handling (Extreme extensibility)
Gravimetric Scaling Table for 750g Base Flour at 90% Hydration
Neighborhood sensitivity across 750g ± 50g flour and 90% ± 2% hydration (150g starter, 16.5g salt, 1585g dough).
| Batch & Seed Spec | Flour Breakdown | Levain Split | Corrected Water (90% Ref) | Salt & Dough Mass | Apparent vs Locked |
|---|---|---|---|---|---|
| 700g @ 88% (15% Seed) Compact Mix (-50g) | 700g + 53g = 753g (90%/750g ref) | 105g (53gF/52gW @ 100%) | 611g W (vs 616g app @ R1) | 15.1g salt (1416g dough) | 88.7% drift → 88.05% (88% goal) |
| 750g @ 88% (18% Seed) Conservative Pour | 750g + 75g = 825g (90%/750g ref) | 135g (75gF/60gW @ 80%) | 666g W (vs 660g app @ R2) | 16.5g salt (1551g dough) | 87.3% drift → 88.0% (88% goal) |
| 750g @ 90% (20% Seed) [Locked Benchmark] | 750g + 75g = 825g (90%/750g ref) | 150g (75gF/75gW @ 100%) | 668g W (vs 675g app @ R3) | 16.5g salt (1568g dough) | 90.9% drift → 90.06% (90% goal) |
| 750g @ 92% (22% Seed) Open-Crumb Push | 750g + 83g = 833g (90%/750g ref) | 165g (83gF/82gW @ 100%) | 684g W (vs 690g app @ R4) | 16.7g salt (1599g dough) | 92.7% drift → 91.96% (92% goal) |
| 800g @ 92% (25% Seed) Expanded Loaf (+50g) | 800g + 89g = 889g (90%/750g ref) | 200g (89gF/111gW @ 125%) | 707g W (vs 736g app @ R5) | 17.8g salt (1707g dough) | 95.3% drift → 92.01% (92% goal) |
Dynamic Stoichiometric Workbench (668g)
Test custom loaf weights or alternative fermentation schedules directly against the 675g benchmark above.
Bassinage Mechanics for 750g Flour at 90% Hydration (668g Water)
Unadjusted baker's percentages treat 150g starter as a weightless additive on 750g flour, causing 675g water to pool at 90.9% (+0.9% excess over 90%). Accounting for 75g starter flour and 75g starter water via 668g main water (-7g) locks True Total Hydration at 90.06% (target 90%).
At 90% target hydration (90.06%), the 1585g dough (750g flour + 668g water + 150g starter) displays extreme extensibility and slack elasticity (5/5 stickiness). Holding 67g water back from the 601g autolyse protects disulfide cross-links with 16.5g salt.
Bench & Dutch Oven Protocol for 2-Loaf Batch (750g Flour @ 90% Hydration)
- Stage-1 Hydration (601g of 668g Water): Whisk 601g water into 750g base flour and cover for 45 min while 150g starter peaks.
- Stage-2 Double Hydration (+67g Splash & 16.5g Salt): Slap-and-fold 150g culture (75gF/75gW), 16.5g salt, and 67g water to lock 90.06% (90%).
- Gluten Organization (Extreme / Wet Handling): Use damp fingers across 4 coil-fold sets to organize the 1585g (825g total flour) matrix.
- Banneton Retard & Steam Bake (2-Loaf Batch): Shape tightly at +50% bulk volume, chill overnight at 38°F, and load into a 450°F Dutch oven.
Key Baker's Math Questions (Strict True Hydration Water: 668g)
How much water do I deduct for 150g starter in a 750g / 90% recipe?
Deduct 7g of water from the 675g apparent weight (pouring 668g main water instead) to offset the +0.9% surge (90.9%) from 150g starter (75gW/75gF).
How much water do I need for 750g of flour at 90% hydration?
Multiplying 750g by 90% gives 675g apparent water, which drifts to 90.9% (+0.9%) with 150g starter. Weighing 668g main water (-7g cut) locks True Total Hydration at 90.06% (target 90%).
What is the total dough weight for 750g flour at 90% hydration?
Summing 750g main flour, 668g corrected water, 150g starter (75gF/75gW), and 16.5g salt yields 1585g of dough (2-Loaf Batch at 90.06%).