Exact 70% Sourdough Ratio for 400g Flour: 268g Water vs 280g Apparent (1 Small Boule)
Baker's math for 400g flour at 70% (757g dough, 1 small boule): 268g corrected water vs 72.7% drift.
In a 400g flour formula at 70%, naive baker's math (280g water + 80g starter) overshoots to 72.7% (+2.7% above spec) across 440g total flour. Setting your scale to 268g water (-12g deduction) and 8.8g salt in a 757g batch locks True Total Hydration at 70.0% (target 70%).
- Strict True Hydration Water
- 268gLocks True Total Hydration at 70.0% (target 70%, -12g)
- Unadjusted Apparent Water
- 280gPushes True Hydration to 72.7% (+2.7% surge)
- 20% Active Starter & Salt
- 80g / 8.8g40g hidden flour + 40g hidden water
- Stickiness & Rheology
- 2 / 5 StarsBeginner Friendly (Balanced extensibility)
True (70.0%) vs Apparent (72.7%) Matrix for 400g Flour
Comparing 268g corrected water (-12g cut) against 280g apparent water (72.7% drift) on 400g flour.
| Batch & Seed Spec | Flour Breakdown | Levain Split | Corrected Water (70% Ref) | Salt & Dough Mass | Apparent vs Locked |
|---|---|---|---|---|---|
| 350g @ 68% (15% Seed) Compact Mix (-50g) | 350g + 27g = 377g (70%/400g ref) | 53g (27gF/26gW @ 100%) | 230g W (vs 238g app @ R1) | 7.5g salt (633g dough) | 70.0% drift → 67.9% (68% goal) |
| 400g @ 68% (18% Seed) Conservative Pour | 400g + 40g = 440g (70%/400g ref) | 72g (40gF/32gW @ 80%) | 267g W (vs 272g app @ R2) | 8.8g salt (739g dough) | 69.1% drift → 67.95% (68% goal) |
| 400g @ 70% (20% Seed) [Locked Benchmark] | 400g + 40g = 440g (70%/400g ref) | 80g (40gF/40gW @ 100%) | 268g W (vs 280g app @ R3) | 8.8g salt (748g dough) | 72.7% drift → 70.0% (70% goal) |
| 400g @ 72% (22% Seed) Open-Crumb Push | 400g + 44g = 444g (70%/400g ref) | 88g (44gF/44gW @ 100%) | 276g W (vs 288g app @ R4) | 8.9g salt (764g dough) | 74.8% drift → 72.07% (72% goal) |
| 450g @ 72% (25% Seed) Expanded Loaf (+50g) | 450g + 50g = 500g (70%/400g ref) | 113g (50gF/63gW @ 125%) | 297g W (vs 324g app @ R5) | 10.0g salt (860g dough) | 77.4% drift → 72.0% (72% goal) |
Interactive Hydration × Flour Weight Formula Calculator
Compare your exact mixing bowl dimensions, flour protein percentage, or discard weight in real time.
True 70.0% vs 72.7% Apparent Hydration on 400g Flour (80g Starter)
Fermentation enzymatics inside 80g starter cleave proteins across 40g flour while releasing 40g unbound water into your 400g dough. Avoiding the 72.7% (+2.7%) slump of an unadjusted 280g pour requires 268g water (241g + 27g) and 8.8g salt, which locks True Total Hydration at 70.0% (target 70%).
Glutenin macropolymer alignment for 400g flour at 70% hydration improves when 241g water (90% of 268g) swells endosperm proteins for 45 minutes prior to adding 80g acidic levain, 8.8g salt, and 27g reserved water—preventing the 72.7% slump of 280g water.
Step-by-Step Mixing & Folding Protocol for a 757g Batch (400g @ 70%)
- 90% Water Autolyse (241g / 268g): Mix 400g unbleached flour with 241g water and rest covered 45 min to initiate glutenin linking.
- 10% Bassinage & Starter Addition (27g W + 80g Levain): Add 80g starter (40gF/40gW), 8.8g salt, and 27g water for 70.0% (70%) across 440g flour.
- Viscoelastic Folding (757g Batch, Beginner Friendly): Complete 4 coil folds at 30-min intervals to balance balanced extensibility.
- Cold Fermentation & Bake (400g Base): Shape into a taut 1 small boule, chill 14 hrs at 38°F, and bake 42 min total at 450°F.
Frequently Asked Questions for This Hydration × Flour Weight Formula Spec
Why does unadjusted 280g water cause a +2.7% surge on 400g flour at 70%?
Because 70% is below 100% starter hydration, 80g starter (40gW / 40gF) raises 280g water to 320g over 440g flour (72.7%). Cutting 12g to 268g locks 70.0%.
How much starter and salt go into 400g flour at 70% hydration?
At 20% inoculation and 2% total-flour salt, combine 400g flour with 80g active starter (40gF + 40gW), 268g water, and 8.8g salt (2% of 440g total flour) for a 757g batch.
How sticky is a 400g flour sourdough at 70% hydration (268g water)?
At 70.0% (target 70%) with 268g water and 80g starter on 400g flour, rheology scores 2/5 stars (Beginner Friendly) with balanced extensibility.