Recipe hydration

40% Rye Hearth Loaf — Hydration Guide

Target 78%. Workable range 7582%.

Why this hydration for 40% Rye Hearth Loaf?

40% rye hearth loaf balances rye character with wheat structure — moderately dense, deeply flavored, with decent oven spring. This is a popular 'everyday rye' format in German home baking. Sourdough preferment critical: 100% hydration rye levain for flavor development. Cold retard improves handling.

Flour mix: 40% rye medium · 55% bread flour · 5% whole wheat.

What 78% hydration does for 40% Rye Hearth Loaf

At its 78% target, 40% Rye Hearth Loaf bakes up with a very open, holey, translucent crumb — the hallmark of a high-hydration hearth loaf, at the cost of slack, sticky dough that needs confident handling. That's why the style sits where it does on the scale — push it much drier and it tightens toward a sandwich loaf; push it much wetter and it slackens past what the hearth structure can hold.

Worked water math for a 500 g batch

40% Rye Hearth Loaf ingredient weights for 500 g flour at 78% hydration
Flour500 g (100%)
Water390 g (78%)
Salt10 g (2%)
Levain115 g (~23%)

The levain already carries some of that flour and water. The calculator below subtracts its contribution so the numbers you actually weigh at the bench hit 78% exactly.

How this flour mix drinks

40% Rye Hearth Loaf uses 40% rye medium · 55% bread flour · 5% whole wheat. The 45% whole-grain portion (rye medium, whole wheat) absorbs more water than white bread flour, so the dough feels a touch stiffer than its 78% number suggests — give it a longer autolyse and hold back a little water to add later if needed.

Technique at 78%

Autolyse wheat flours 30 min with water. Add rye flour, levain, salt. Mix thoroughly by hand (rye prevents useful kneading). 3-4 coil folds over 3h bulk at 76°F. Shape in floured banneton. Cold retard 8h. Bake in preheated dutch oven at 475°F: 20 min lid on, 20 min lid off.

Calculator pre-set to 78%

Flour to add
450 g
Water to add
340 g
Salt
10 g
Levain @ 100%
100 g
Total dough
900 g
Effective hydration
78%
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.

Open 80% hydration guide →

40% Rye Hearth Loaf hydration — FAQ

What hydration is 40% Rye Hearth Loaf meant to be?

Target 78% — that's 78 g of water per 100 g of flour by weight. The workable range is 75–82% depending on your flour and handling skill.

How much water do I need for 40% Rye Hearth Loaf?

Multiply your flour weight by 0.78. For a 500 g flour batch that's 390 g water, plus about 10 g salt (2%). The calculator on this page also subtracts the water your levain already contributes.

Can I make 40% Rye Hearth Loaf at a lower hydration?

Down to about 75% gives a tighter crumb and much easier, less sticky handling — a good starting point if you're new to this style. Below 75% the open, characteristic 40% Rye Hearth Loaf texture is largely lost.

Can I make 40% Rye Hearth Loaf at a higher hydration?

Up to about 82% opens the crumb further but demands confident wet-dough handling (more folds, a well-floured bench, decisive shaping). Above 82% the structure usually slackens and the loaf spreads instead of rising.

Source: Hamelman — Bread 3rd ed., 40% Rye formula