The Life of a Grain of Wheat, from its Birth to Our Plate



From grain to wheat stalk


Hidden in the earth, a grain of wheat, sown in October or November, sprouts in April and develops through the end of the summer. Five roots irrigate this grain, which produces three leaves.

A hollow stem grows in spurts marked by nodules, each of which will produce more leaves. The sheath (peduncle) at the top, which encloses the stem, opens up in June for the flowering and then for the formation of grains (45-60 per stalk).

The stalk, bent over at first, gradually straightens up and the grain thickens.

From a tender green color (at the “milky” stage), it turns yellowish green (at the “mushy” stage) and is easily crushed.

Then the grain ripens: shiny, hardened, it takes on a lovely yellow color.

It is harvest time, because beyond this stage the grain turns dull and falls off the stalk on its own.


From harvest to milling


While waiting to be transformed by the mill, the wheat is stored in huge silos that protect it from rodents, light, and humidity.

The mill makes flour with about one-third of the harvest. The rest is divided among other alimentary uses (pastas and crackers, cattle feed, and cereal exports).

People often think that all the miller has to do is grind wheat. Well, thanks to technological progress, his trade has become much more complex. Just consider:

As soon as the wheat arrives at the mill, samples are taken from each batch to be analyzed by the in-house laboratory, in order to define the components that correspond to the desired criteria of quality.

From the silo, the wheat is poured into reservoirs called raw wheat bushels, while waiting to have its impurities removed.

In the mill, the wheat is transformed into flour in five major steps that are entirely automated:


  1. Cleaning


    Une tige creuse, croît, par à-coups marqués, en nœuds qui porteront chacun d'autres feuilles.

    To eliminate the first impurities, the wheat is moved through cleaner-separators where screening through vibrating sieves eliminates the dirt and removes all the elements that are not the same size as a grain of wheat.

    After they go through a rock remover that eliminates all the undesirable little pebbles, only the healthy grains of wheat remain in the chain.

    Magnetic filtering removes all forms of metal.

    Once this sorting has been done, the grains are moistened in a humidifying tumbler, then placed in a bushel to rest.

    The miller’s whole art consists in bringing the grain of wheat to the right degree of humidity that will make its kernel just friable enough to be crushed, but will also keep the husk from being pulverized during the milling, which would soil the flour.

    When the wheat comes out, as a security measure, “wheat brushes” eliminate any remaining little particles. A magnetic sensor draws out any metallic debris that might have come from the machines encountered in the production chain.

  2. Broyage (break system)


    During this operation, the husks of the wheat grains are broken and detached from their kernels.

    Four different products result from broyage:

    --overtails, or feeds (refus): pieces of husk with the starchy kernels; these will go through a second grinding to produce both fine and coarse bran;

    --semolina (semoules): these large particles of the husk go to claquage, a special grinding process for semolina;

    --middlings, or branny material (finots): these very small particles of husk are sent for reduction (convertissage) into even smaller particles that are still larger than those in flour;

    --broyage flour (farine de broyage): flour from this initial grinding will be mixed later with the flour produced by claquage and convertissage .

    The grains are ground four or five times between two grooved metallic cylinders that turn in opposite directions and are gradually brought closer together.

    At each grinding, sifting machines (superimposed sieves turning in a horizontal circular movement) separate and categorize or grade the products obtained according to their size. Thus they separate ground flour from flour that has not been removed from the husk; this latter goes back to the cylinders to be ground again.

  3. Claquage


    After the semolina is separated, it passes four or five times through smooth cylinders. Claquage gives rise to three types of products:

    --middlings (finots), which will go through convertissage;

    --wheat germ, which is extracted at this stage (it is oily, and could turn the flour rancid);

    --the claquage flour, which goes into a storage bin with the flour from the broyage and convertissage processes.


  4. Convertissage


    The middlings obtained earlier go through reduction rolls (smooth cylinders) six or seven more times.

    Two types of products emerge at this phase:

    --convertissage flour

    --the rest of the middlings, called shorts (remoulage).

    The three flours extracted from the three grinding processes (broyage, claquage, and convertissage) are mixed and sifted one more time.

    They are then homogenized in a mixer and stocked in bulk or in bags.



In France, every mill has its own milling procedure, called a diagram, the same word used to describe a baker’s recipe. In other words, every mill has a number of machines designed to privilege one or another of the stages described above (grinding, regrinding, or sifting). It can be visualized as a kind of mechanical choreography.


The Minoteries Viron have opted for a long procedure, that is, for a gradual, multi-stage grinding of the grain.


At the end of the process, a laboratory analyzes the flour produced and determines its characteristics by burning very small quantities at 1652o F (900o C) and weighing the ashes that remain. The flour is classified by “type” according to the weight of this residue.

Flour of type 45 is used for pastry, Viennese breads, and cooking.

Flour of type 55 is used by bakers to make their bread.


The Retrodor Baguette is made from type 55 flour.


Today in a supermarket, most of us don’t even think about the source of the meat packaged under plastic or the plethora of processed foods, transformed endlessly. As early as the eighteenth century, political economists were chiding urban consumers impatient with the complexities and uncertainties of the provisioning system by reminding them that wheat did not grow under the paving stones of the narrow streets of the time.


Today, the sight of a loaf of bread should remind us of the three stages of the overall production cycle.

  1. Wheat cultivation: the choice of specific varieties in terms of their “baking value,” “rational” agricultural methods that limit chemical inputs and risks of pollution while enhancing “traceability,” and so on.

  2. Milling, the most discreet or least celebrated stop. We have just seen how exacting and labyrinthine the operations are, even if computers have enabled tighter controls. The famous woman of letters of the age of Louis XIV, Madame de Sévigné, captured the indispensable role of the miller when she complained during a period of extremely inclement weather: “We are dying of hunger on a huge mound of wheat.” When flooding or freezing or drought impeded mill wheels from turning, flour could not be milled and bakers, no matter how ingenious, could not make bread.

  3. Baking the ultimate stage and the one closest to us, the point at which we find our pleasure.

    Three age-old professions, three sets of calloused hands at work, three forms of passion: as the central European proverb has it, all good things come in threes.


Visit to a Mill