Hydration guide
Medium Rye Flour Hydration Guide
Workable range: 80–95% · Absorption: 1.080× bread flour · Midpoint target: 88%
How Medium Rye Flour behaves at each hydration
Medium rye contains most of the rye grain with moderate bran content. Rye proteins do not form gluten like wheat proteins — instead, rye structure comes from pentosans (soluble fiber) that absorb 8-10x their weight in water. This means rye dough is sticky, paste-like, and requires different handling than wheat. Hamelman's reference specs target 80-95% hydration for rye-dominant doughs. Central Milling's Organic Medium Rye is the US reference. At 20-40% in a blend with bread flour, medium rye adds color, flavor complexity (tangy, earthy), and extends keeping quality. At 100%, expect dense crumb and strong sour flavor.
Substituting Medium Rye Flour for bread flour
Absorption multiplier: 1.080×. When substituting for bread flour, add about 8% more water. For example: a 75% bread-flour recipe becomes 81% when using 100% Medium Rye Flour.
The calculator below is pre-set to 88%. Adjust the slider to match your target. Salt and levain percentages are the flour-independent defaults (2.0% and 20%).
Technique at target hydration
Do NOT knead rye dough (tears pentosan structure). Mix to incorporate, then rest. Very short bulk ferment (2-3 hours at 76°F) — rye ferments fast. Wet hands for shaping. Use a pan or tight banneton. Bake at higher initial temp (500°F) for 15 minutes, then reduce. Internal temp 205-210°F for doneness.
Calculator pre-set to 88%
- Flour to add
- 450 g
- Water to add
- 390 g
- Salt
- 10 g
- Levain @ 100%
- 100 g
- Total dough
- 950 g
- Effective hydration
- 88%
How the math works
Total water = flour × hydration %. Your levain contributes 50 g flour + 50 g water — both count toward the totals. You add only the remainder as fresh flour and water.
Salt % is computed on total flour weight, not final-dough flour.