From wheat to flour: the stages of milling

Before it becomes the morning’s bread, wheat has a long road to travel. For centuries that road ran through a stone millstone; today precision machines do the same work, faster, without losing the essential part: separating the grain, gently, to get the best out of it.

First, clean the grain

You don’t mill wheat as it arrives. It first goes through cleaning: sieves and air currents drive out the straw, the dust, the foreign bodies. Then it is conditioned: a carefully measured trickle of water softens the bran so it peels away from the floury kernel without tearing.

Then, break without crushing

The grain passes through a series of fluted roller mills that break it down a little at a time. The aim is never to crush it at once, but to separate the kernel from the bran as finely as possible.

Finally, sift and grade

The broken grain is then sifted: plansifters sort the particles by size. The semolina goes back for further passes; the flours are graded by their extraction rate — the amount of flour obtained from 100 kg of wheat.

And the “type”, in all this?

A flour’s type (T45, T55, T65, T80, T150…) matches its ash content: the mineral matter left after combustion. The higher the type, the more wholemeal the flour.

Sources

• Industrial milling techniques (reference works)
• Agricultural and food encyclopaedias