Flour comes from wheat berries. Wheat spikes hold the wheat berries. If you press a wheat spike with your fingers, you’ll notice that the wheat berries are popping out from the spikelets. If you blow away the chaff, the grains remain.
- the endosperm (83%) is the biggest part and contains starch granules, iron, B vitamins
- the bran (14.5%) - is the outer layer that contains fibres, proteins, B vitamins and trace minerals
- the germ (2.5%) - is the embryo of the seed, contains lipids, B vitamins and minerals
- Whole wheat is ground wheat berry with nothing removed from it. This means that almost 15% is bran and makes your bread a failure if you do not understand how to treat it.
The bran requires more time to be hydrated, I would say at least 4 hours minimum.
The bran is very thirsty, it needs a lot of water to hydrate properly. That's why the hydration of my dough is 85%. You may use a trick to sift the bran and hydrate it separately from the flour. - The bran blocks the gluten network development because it acts as a barrier between the protein chains that want to bond. This means that your dough lacks extensibility and cannot hold gas as a white flour dough would do.
- Whole wheat contains less protein percentage. At least in my region. I buy local and organic every time I can. Local means Belgium that has less sun than Mediterranean countries. Less sun means also less gluten/protein content. Usually, I find in Belgium only 10-11% protein content flours. You might not face the same if you live in sunny Italy for example. Although it is not an issue to have less gluten in the flour, this has a direct impact on the openness of the crumb.
- Whole wheat ferments faster so you need to cut the fermentation earlier.