Extreme 85% Hydration Sourdough (300g Flour): 226g Base + 25g Bassinage (1 Small Boule)
Ciabatta-style 85% formula on 300g flour (618g batch) with 25g bassinage staging and -4g starter deduction.
In a 300g flour formula at 85%, naive baker's math (255g water + 60g starter) overshoots to 86.4% (+1.4% above spec) across 330g total flour. Setting your scale to 251g water (-4g deduction) and 6.6g salt in a 618g batch locks True Total Hydration at 85.15% (target 85%).
- Strict True Hydration Water
- 251gLocks True Total Hydration at 85.15% (target 85%, -4g)
- Unadjusted Apparent Water
- 255gPushes True Hydration to 86.4% (+1.4% surge)
- 20% Active Starter & Salt
- 60g / 6.6g30g hidden flour + 30g hidden water
- Stickiness & Rheology
- 5 / 5 StarsExtreme / Wet Handling (Extreme extensibility)
300g Flour at 85% Hydration: 2D Scale & Starter Sensitivity Matrix
Pre-computed gram weights around 300g main flour where 251g water locks True Total Hydration at 85.15% (target 85%).
| Batch & Seed Spec | Flour Breakdown | Levain Split | Corrected Water (85% Ref) | Salt & Dough Mass | Apparent vs Locked |
|---|---|---|---|---|---|
| 250g @ 83% (15% Seed) Reduced Flour (-50g) | 250g + 19g = 269g (85%/300g ref) | 38g (19gF/19gW @ 100%) | 204g W (vs 208g app @ R1) | 5.4g salt (492g dough) | 84.4% drift → 82.9% (83% goal) |
| 300g @ 83% (18% Seed) Stiffer Step (-2%) | 300g + 30g = 330g (85%/300g ref) | 54g (30gF/24gW @ 80%) | 250g W (vs 249g app @ R2) | 6.6g salt (604g dough) | 82.7% drift → 83.03% (83% goal) |
| 300g @ 85% (20% Seed) [Primary Formula] | 300g + 30g = 330g (85%/300g ref) | 60g (30gF/30gW @ 100%) | 251g W (vs 255g app @ R3) | 6.6g salt (611g dough) | 86.4% drift → 85.15% (85% goal) |
| 300g @ 87% (22% Seed) Wetter Step (+2%) | 300g + 33g = 333g (85%/300g ref) | 66g (33gF/33gW @ 100%) | 257g W (vs 261g app @ R4) | 6.7g salt (623g dough) | 88.3% drift → 87.09% (87% goal) |
| 350g @ 87% (25% Seed) Up-Scaled (+50g) | 350g + 39g = 389g (85%/300g ref) | 88g (39gF/49gW @ 125%) | 289g W (vs 305g app @ R5) | 7.8g salt (727g dough) | 91.0% drift → 86.89% (87% goal) |
Real-Time Dough & Starter Scaling Sandbox
Scale this Ultra-Wet 85% Hydration Sourdough Fo specification up or down on your digital scale with zero hydration drift.
Bassinage Mechanics for 300g Flour at 85% Hydration (251g Water)
Flour-water coupling on 300g base grain changes once 60g liquid levain (30g F / 30g W) enters the mixer: 255g main water creates 285g total water (86.4%, +1.4% overshoot). Scaling back 4g to 251g water over 330g total flour locks True Total Hydration at 85.15% (target 85%).
Because 30g starter flour inside 60g levain carries lactic proteolysis into 300g fresh flour, unadjusted 255g water (86.4%) causes slack tearing. Deducting 4g to 251g water (85.15%, 5/5 stickiness) keeps the 618g loaf inside the extreme / wet handling window.
Step-by-Step Mixing & Folding Protocol for a 618g Batch (300g @ 85%)
- Endosperm Saturation (300g Flour / 226g Water): Rub 226g water into 300g flour (saving 25g of 251g) and rest 40 min.
- Ionic Salt & Culture Mix (60g Levain + 6.6g Sea Salt): Pinch 60g peaked starter and 6.6g salt dissolved in 25g water into the 618g batch (-4g vs 255g).
- Rheological Laminations (85% / 85.15%): Perform 1 bench lamination plus 3 coil folds every 35 min for slack tenacity across 330g system flour.
- Cold Proof & Dutch Oven Spring (618g): Preshape at +50% expansion, stitch into a banneton for 12–16 hrs at 38°F, score at 45°, and bake at 450°F.
Diagnostic Answers: Ultra-Wet 85% Hydration Sourdough Formula fo
How does changing starter from 20% (60g) to 15% (45g) affect 300g flour at 85%?
Dropping starter from 60g to 45g on 300g flour reduces hidden starter water from 30g to 23g, raising required main water from 251g to 252g for 85%.
What baking temperature works best for a 618g loaf (300g flour @ 85%)?
Bake your 618g (1 Small Boule) dough made from 300g flour, 251g water (85.15%), 60g starter, and 6.6g salt in a preheated 450°F (232°C) Dutch oven for 20 min covered + 22 min uncovered.
How much water do I need for 300g of flour at 85% hydration?
Multiplying 300g by 85% gives 255g apparent water, which drifts to 86.4% (+1.4%) with 60g starter. Weighing 251g main water (-4g cut) locks True Total Hydration at 85.15% (target 85%).