How to calculate bread dough: flour, water and sourdough

Bread recipes use baker's percentages too: all the flour is 100 %, and water, salt and starter are shares of it. German bakers also use dough yield, Teigausbeute or TA for short: the weight of dough made from 100 g of flour. TA 170 means 70 g of water for 100 g of flour, so 70 % hydration. The higher the yield, the softer the dough.

German flour types tell you how much mineral content is in the flour, and so how much of the outer grain was milled into it. The higher the number, the more water the flour absorbs. Type 550, close to bread flour, takes about 63 %, type 1050 about 70 % and whole wheat about 80 %. Rye takes even more: type 1150 a good 75 %.

Mix flours and you mix their water too: a loaf of half type 550 and half whole wheat lands in between. Salt goes in at about 1.8 % of the flour, roughly 9 g for 500 g.

Ripe starter raises the dough and gives it flavour. Many recipes use just under 20 % of the flour, about 100 g for 500 g. More starter makes the dough rise faster, less makes it slower.

A wheat sourdough with 20 % starter takes a whole working day at 21 °C until it's ready to bake. If you'd rather wait overnight, use less starter or let the dough rise in the fridge. While it rises, stretch and fold it about four times, half an hour apart, to give it strength.

A little yeast beside the starter makes the dough rise faster and more reliably. The yeast makes up what the starter lacks for your schedule, and the sourdough stays for the flavour.

Rye behaves differently from wheat. Its dough needs acid, or the crumb stays sticky and wet after baking. That's why bread with more than half rye is made with sourdough.

For that you start a sour the day before: just under 40 % of the rye flour with the same weight of water and a little starter. It ripens overnight at room temperature, about 12 hours, and all of it goes into the dough the next day with the rest of the flour. That is more than you might expect: for a 1 kg loaf of half wheat and half rye flour it is a little over 200 g of sour, started with just 20 g of starter.

How long the sour ripens is up to you: the longer it may ripen, the less starter it needs, little for a whole day. Without yeast the sour then raises the dough: less time needs more sour, more time less, as long as the rye gets enough acid. With half rye at 23 °C that is just under four to a good five and a half hours. For faster, or overnight, add a little yeast. Rye dough is only mixed until even, not kneaded or folded. After baking it keeps setting as it cools, so cut it only once it is completely cold.

Seeds and flakes make bread moist and hearty, but they draw water out of the dough. Soak them first, ideally overnight. Seeds such as sunflower or pumpkin seeds take up about half their weight in water, oat flakes and cracked grain about their own weight, linseed one and a half times, and dried old bread even twice.

Vegetables bring water too, but not always as much as you'd think. Grated raw carrot holds on to nearly all of its water, while puréed pumpkin gives about two thirds of its weight to the dough. Take that off the recipe's water, or the dough turns too soft.

The easiest way to plan is backwards from baking: when should the loaf come out of the oven? Take away the proof, the kneading, the sour and the soaker, and you know when to start. For bread at breakfast, that often means mixing the dough the evening before.

Preheat the oven with a tray or pot to about 225 °C, top and bottom heat. Load the loaf with steam, from a dish of water on the oven floor or with the lid on the pot, and turn it down to about 185 °C after a quarter of an hour.

Baking time grows more slowly than the weight: a 500 g loaf takes about 35 minutes, a 1 kg loaf just under 50 and a 1.5 kg loaf about an hour. It is done at about 97 °C in the middle, or when it sounds hollow as you tap its base.