صناعة الطحن .. كتاب في سبيل موسوعة علمية .. الدكتور أحمد ذكي

Milling industry

The milling industry began with grinding in stone pestles
More like mortar. A block of hollow stone. A heavy pestle, also made of hard stone, lands on the wheat inside.

Then the mill was replaced with the pestle: two round stones, the top of which was turned over the bottom with the hand, and in the middle of the top was a round hole into which the wheat was poured, and it ran between the two disks and was stopped.

These mills grew until they were run by animals such as bulls, or by the force of water rushing from its natural streams, or by fans of air that extended high toward the sky. They slit its surfaces that touch the wheat until it has sharp edges that tear the grain. This was very common in the Middle Ages in Europe.

Then the flour industry entered the newer stage with the introduction of grinding cylinders. It was the only one that was able to extract white flour and white loaf from wheat of the hard type. They made them of steel, each rotating horizontally to attach to its other. They made grooves with sharp edges on their surfaces. It crushes the grain of wheat completely, but it still retains its germ (which is what the plant grows from when it is placed in the ground), and it also retains its husk (which is the bran or germ). This makes it easy to separate them later from the white flour.

We summarize the process by saying: It consists of many steps of crushing, then separating, then crushing, then separating. The crushing begins lightly, after which air is used to carry the bran that has been separated from the grain. Then the crushing intensifies, and sieves are used. The more the process is repeated, the whiter the resulting flour.

The weight of the resulting pure flour varies depending on the grain, some of which reach 70 percent of the weight of the grain, and this is normal in bakeries. Some of them are further purified and reach only 56 percent of the weight of the grain. and so on . And for every purpose.

- Discovery of yeast:

Just as the type of loaf advanced with the advancement of the milling industry, so too has its industry advanced in modern times, and public bakeries have expanded with the discovery and separation of yeast.

This happened at first using yeast that they raised on the mash used in making beer. This happened in the late eighteenth century. When the nineteenth century began, this yeast was widely used in England and northern Europe. The expansion of the bread industry and its trade was increased by the yeast that they produced as pressed in the United States, and they brought it from the distilled wine industry. This was in 1868.

The major step was taken in the year 1883, in which the cells of different pure and pure yeasts of various types were separated, their properties were studied, and what was most suitable, proven, and most conducive to the desired result was chosen. With this, bread factories in general were able to always produce loaves with fixed characteristics that did not differ depending on the yeast.

- Wheat grain:

It usually consists of a golden crust, as this is the bran. It covers the heart of the grain. In the heart of the seed, at one end of it is the germ, or the embryo, which is the part in which the future plant is represented. If the seed is placed in the ground and hydrated, the embryo begins to move, one end of it rises to form the stem, and one end of it descends and forms the roots.

(In many rural areas of Sweden and Norway, bread is baked like this in ovens similar to those of the people of the East. This Swedish woman bakes an amount of oat and barley bread sufficient for several months, and it is the prevailing bread in those northern regions.)

Flour aims to get rid of the crust and the germ together, as we mentioned, but in this way much of the iron and vitamins in the grain are lost from the bread (Thiamin, which is Vitamin B1, Riboflavine, which is Vitamin B2, and Nicotinic Acid), and not in Vitamin C. C.

What remains of the composition of the seed is that which is intended to be the plant’s food when it sprouts, and before it is able to earn its own food. It is that very beneficial remainder that we aim for, when making flour, and extract it, and call it white flour.

This consists of two things:

Starch, which is like all other starches found in rice and potatoes, and from it every eater derives the energy it contains
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Then protein, which is more than one type, if placed in water turns into an elastic substance known as gluten, which is the sticky substance that makes dough stick to the human hand. If the dough was only starch, it would have to be washed off with water.

As it is a protein, it fulfills some of the body’s need for proteins when the person eats bread.

But its function in fermentation is now our purpose of discussion. Yeast chemically affects some starch, decomposing it, and a gas is released from its decomposition, which is carbon dioxide. This sticky substance traps him. As fermentation increases, the dough increases in size due to this gas. If the loaf of dough is placed in the oven after that, the volume of carbonic gas in the loaf increases due to the heat and it swells, then the gas escapes.

The result: a fluffy loaf that is light when chewed
Intensely.

Two things can be concluded from this:

(1) The loaf becomes heavy and thickens if it is not fermented.
(2) In order for the loaf to leaven and retain the resulting gas, its flour must contain gluten. So, not every flour makes a light, fluffy loaf. It is not made from potatoes, rice, corn, or barley.
It is made from oats.