Flour is the basic ingredient of bread along with salt and water.
Wheat flour is by far the most common one.
In the market wheat flour comes in different kinds:
White flour: Is the innermost part of the grain. It is mostly starch and protein. The protein, when kneaded, makes the gluten, an elastic substance that is vital to make a light and tender loaf.
In the supermarket you will find some three different kinds of white flour: for pastries; all purpose and hard for bread. They differ basically in the amount of protein they contain.
Pastry flour is the finest and lightest one. It is mostly starch. It is appropriate to make fine pastries and cakes but is no good for bread.
All Purpose: Containing more gluten that pastry flour, All Purpose is used for most everything, even for bread, though it is not the best option.
Hard, for Bread: This is the one with the maximum amount of gluten and is the best for breadmaking.
White flour hard for bread is made out of hard wheat. In our area is very common the winter red hard wheat variety. This variety is sown around us at the end of fall; the little plant sleeps during the cold winter under the snow and wakes up in spring to grow, mature and be harvested. Durum wheat, instead, is a bigger and softer wheat kernel that is used to make semolina and pastas.
Whole Wheat Flour is, essentially, the whole wheat kernel finely milled. Now, not every whole wheat flour is the same.
There is a problem with this flour: the germ of the grain contains oil that could get rancid over the time by the action of the oxygen of the air. This makes whole wheat flour a delicate, perishable item.
If poorly taken care of, can easily get moths; wheat weevil or become rancid.
This kind of whole grain wheat flour is not sold in supermarkets due to its rather short shelf life. The whole wheat flour sold by supermarkets is but a mix of white flour and wheat bran or, in the best of cases, a degerminated whole wheat flour.
The best version of a whole grain wheat flour is the one from stone mills. This kind is available only in selected health or bulk stores.
The flour I use comes from local wheats around us and is finely stone ground without sifting anything away by Grain Process Enterprises in Scarborough, Ontario. I renew my stock continuously. This is part of the reason my bread is so tasty.
Whole kernel or cracked wheat: Some bread traditions use to add the whole of cracked grain to the bread. Rye is used in like manner, mostly in the north of Europe and Russia.
Spelt flour is also used in bread. A dough made with spelt is weaker than a wheat dough. It is used mostly by people intolerant to wheat.
Rye contains some gluten, but some natural gums in the grain prevent it from developing to make an elastic dough for bread. It is used mixed with some wheat flour to obtain a spongy crumb. It is possible to make a 100% rye bread, which is an art. The resulting loaf is dense and heavy, yet very tasty. A very dense bread in North Germany is made only with a coarsely ground rye meal and a long cooking process at low temperature (120°C or 250°F) taking some 16 to 24 hours in lidded pans in an oven full of steam.