Flour, essential ingredient

The key ingredient in breadmaking is wheat. It is grass, like all cereals and the grass in our garden. Wheat was grown and selected for millennia, so today we have high yielding varieties.
This cereal, when finely milled and mixed and kneaded with water, develops the gluten. Small protein particles contained in the grain stick to one another forming a greyish substance that is elastic and resistant to stretching. When gluten is diffused through the dough, it creates a three-dimensional network structure, something like a sponge, which retains the carbon dioxide gas formed by the action of yeast that makes the dough rise, increasing its volume significantly.
Other cereals such as Kamut, Spelt, Rye and Barley are old varieties of wheat and also contain gluten but in a smaller amount.

Rye has protein but does not develop gluten when kneaded because it also contains some gelatinous substances that envelop protein particles, preventing them from sticking together.

Barley contains very little gluten. Flat barley cakes can be made with or without yeast, but it is not possible to make a fluffy leavened bread with barley flour. The addition of barley or oats flour to regular bread will give it a mealy texture that may displease some people. They have little to no use in bread baking.
When I want to include oats or barley in bread, I use a very coarsely ground meal instead (steel cut oats; cracked barley). The non-pre-cooked oats coarse meal can be added without soaking, right with the other ingredients before kneading. It will absorb a large amount of water from the dough making it too stiff. So if oats meal is used, it is necessary to add more water than usual. The dough will be very soft and sticky at first, but during the fermentation time the oats will absorb the excess water and the dough will achieve its proper consistency.
Barley is harder than oats and takes longer to absorb water and become softer. If it is added first, together with the other ingredients, grain pieces will remain hard to chew when eating the bread; for that reason, it should be soaked overnight before being added to the bread dough in the morning. Another way to soften cracked barley faster is placing it in a container and covering it with abundant boiling water. It should not be taken to boil or else the barley will soften too much, the starch will modify its structure and absorb too much water. This is not beneficial to the bread. Instead, just add boiling water and let it soak until cool.
We must not add any parboiled cereal to the dough because the starch contained within has been modified from parboiling, resulting in a clammy breadcrumb.
Flours: We find abundant white wheat flour in the supermarket or grocery store. Three kinds of white flour are usually available: 1. Pastry; 2. All purpose and 3. Bread. The difference between these flours resides mostly in their gluten content. Pastry flour is very thin and has little gluten as it is mostly starch. It is good for cookies and cakes but is too weak for bread. All-purpose flour contains certain amounts of gluten which can vary by brand and country. It can be used for bread but is not the best choice. Bread flour, on the other hand, contains a higher percentage of gluten, making it a strong, elastic dough. I recommend it to make bread.
About 20 years ago, in Canada, I used regular white bread flour with 13% gluten. It was mostly from southern Manitoba, near the border with the United States. Today’s Canadian flour, as a consequence of intense farmland exploitation, is around 12% gluten, or even less.
I also use organic unbleached white flour, which I buy from a specialized provider. It is wonderful in strength and flavour and has a good 13% gluten content. However, it is twice the price of regular flour.
European flours are low in gluten. For bread, they should be reinforced by mixing them with stronger flours imported from America and Canada (Manitoba).
The percentage of gluten in the flour may vary from one country to another. If your flour is weak, you can strengthen it a bit by adding ¼ cup dry gluten powder per kilogram or 6 cups of flour. (In Ontario, Canada, I find two kinds of gluten powder: 60% and 80% gluten content in health food and bulk stores).
Dry gluten powder should be used very sparingly. A quarter cup per kilogram of flour is a good proportion. If we add more, we’ll notice that the breadcrumb texture changes, becoming firmer and dryer.
Stonemill ground flours are the best. The reason for this is that these flours contain all parts of the grain, and therefore all the nutritional richness of the grain. Moreover, the bran is shredded into small particles and does not encapsulate substances that ferment in the intestine.
Whole wheat flour sold in supermarkets and food stores is most commonly a mixture of white flour and bran. Semolina and germ, which contain the vitamins and enzymes, the “real food” of the wheat, have been separated. The bran comes in the form of flakes that tends to curl in the intestine, encasing substances that can not be appropriately digested and producing inconvenient fermentations.
The ground wheat in a stone mill, however, is totally shredded to a fine powder. Bran is also reduced to small particles that do not cause problems, but rather provide good fibre for better performance of the intestines.
These types of natural flours are not sold in supermarkets because of their short shelf life. The oils and enzymes in the seeds can ferment, get rancid or can be attacked by moth and weevil. In many countries their sale is prohibited in supermarkets and grocery stores, being legal to sell only in their mill of origin, or in specialized health food stores.
Some small grain mills are offered on the market for use at home. to ground fine whole wheat flour and a variety of non-oily seeds to be used in bread. Some modern blenders, with powerful motors, can be used to grind small amounts of seeds. If you use one of those you must take care not to burn the flour by the heat generated by the intense work of the blades.