Loaf 15: high hydration, 70% to 85%
Added water goes from 240 g to 300 g and the dough becomes a batter you could pour. On a wheat dough 85% would be a disaster at this stage. On 70% rye it is close to right, and this is why.
This is Loaf 15 of 16, and the one thing that changed from Loaf 14 is water: added water goes from 240 g to 300 g, which takes total water from 280 g to 340 g and hydration from 70% to 85%.
That is the last water step in the course. Read the whole course's hydration column and it goes 60%, then 70%, then 85%, and never once backwards.
The frozen four
Still unchanged: 400 g flour, 8 g salt (2%), one 9 x 5 inch (23 x 13 cm) loaf pan, and an oven at 375°F / 190°C.
The formula
| Ingredient | Grams | Cups / spoons | Baker's % |
|---|---|---|---|
| All-purpose flour | 80 g | ⅔ cup | 20% |
| Whole rye flour | 280 g | 2¾ cups | 70% |
| Water | 300 g | 1¼ cups + 1 tsp | 75% |
| Sourdough starter (100% hydration) | 80 g | ⅓ cup | 20% |
| Fine sea salt | 8 g | 1⅓ tsp | 2% |
Frozen: 400 g flour · 8 g salt (2%) · 9 × 5 in pan · 375°F / 190°C · Hydration: 85% (340 g water on 400 g flour)
The water row reads 75% and the hydration line reads 85%. Both are right. The row is added water only; the hydration figure is total water, and the extra 40 g arrives inside the starter, which is half flour and half water by weight. A starter is not an extra ingredient sitting alongside the loaf, it is part of the loaf.
The method
- Feed your starter and wait for it to peak at 75°F / 24°C.
- Mix everything thoroughly, 3 to 4 minutes. It is now a thick batter you could pour, closer to Loaf 1 than to Loaf 9.
- No folds. Bulk 3 to 4 hours at 75°F / 24°C, to the gate below.
- Pour it into the greased pan and wet-spoon the top level.
- Fridge at 38 to 40°F / 3 to 4°C for 12 hours. Bake from cold at 375°F / 190°C, 65 to 75 minutes.
- Cool completely, wrap, and rest a full day at room temperature before slicing.
Why this works
85% hydration on a wheat dough at this point in the course would be an unmanageable soup. On 70% rye it is close to right, and the reason is the same reason rye behaved so strangely at Loaf 13.
Rye cannot make gluten. Its secalins do not form the continuous network that wheat's gliadins and glutenins do (American Society of Baking). What rye has instead is arabinoxylans, the pentosans, and they are the main water-binding polymers in the dough. They hold several times their own weight in water (review of rye constituents and processing).
So the water you just added does not go slopping around loose. Most of it gets bound, and the rest of it does something useful in the oven: more water means more starch gelatinises as the loaf heats, and gelatinised starch is what a rye loaf is actually built out of. That is where a good rye gets its dark, moist, almost custardy crumb.
The thing to notice is that the course's pourable batter at Loaf 1 and its pourable batter at Loaf 15 are pourable for completely different reasons. Loaf 1 was fluid because 41% sugar and 20% fat kept the flour proteins from linking up. Loaf 15 is fluid because there is simply a lot of water and no gluten network to make it behave like a dough. Same texture in the bowl, nothing else in common.
How you know it's ready
Poured level in the pan is the starting picture. By the end of the bulk the surface is pocked with small bubbles all over and the batter has lifted by about a quarter. That is 3 to 4 hours at 75°F / 24°C, and the look is the instruction.
Bake until the centre reads 205 to 210°F / 96 to 99°C. On this loaf the thermometer is not optional advice, it is the only readout that works. There is no thump test on a batter bread, the crust tells you nothing, and the top will look finished long before the middle is.
What goes wrong
The failure mode this loaf introduces is a wet, dense band at the bottom of the loaf.
One cause: underbaking. Same oven, same pan, 60 g more water than Loaf 14. It needs 10 to 20 minutes longer, and the crust will be dark and firm well before the middle is done. If you bake this loaf to the colour you baked Loaf 14 to, you will pull it early every time.
The fix is to take the temperature. Not a longer look at the crust, not a hotter oven, not less water. 205 to 210°F / 96 to 99°C in the centre, and nothing else decides it.
When it worked
Dark, glossy-topped, heavy in the hand, with a fine moist crumb that is almost sticky at the knife and clean on the tongue. Strongly sour, deeply grainy.
It is better on day two than day one, which is part of why the rest is written into the method. Cool it completely, wrap it, and leave it a full day at room temperature. Rye's crumb finishes setting long after the oven is off, and a loaf cut warm will read as gummy even when you did everything right.
Bake it twice successfully before moving on to Loaf 16. One good loaf is luck, and two is a skill.
You baked Loaf 15. Did it work?
The course is free. This is the one thing it asks for. Thirty seconds, and it is how the next baker gets a better loaf.