How semolina is milled

Durum is so hard it shatters into coarse grit, and millers sell that grit as semolina instead of grinding it finer.

stations: 6
things upstream: 2
raw sources: 2
step from the ground: 1

The short version

Semolina is a coarse flour milled from durum wheat. Grooved steel rollers set slightly narrower than the kernels crack the grain, flaking off the bran and germ and breaking the starchy center into coarse pieces. Sifting separates the grains by size. Pale yellow durum semolina is the main ingredient in dry pasta.

Clean and temper the grain

Wheat is cleaned of dust, stones and chaff, then dampened and rested so the bran toughens and comes away in bigger pieces.

Goes in
Durum wheat Water
Crack it between rollers

Grooved steel rollers are set a little tighter than the width of a kernel. They flake off the bran and germ and crack the starchy endosperm into coarse pieces.
Sift by particle size

Sieves pull out the pieces of endosperm that meet the coarse standard. Under the Codex rule, no more than 79 percent may pass a 315-micron sieve.

no more than 79% passes 315 microns
Blow out loose bran

Purifiers shake the sifted pieces over sieves while air lifts away flakes of bran, leaving clean, pale endosperm.
Regrind the oversize bits

Pieces that are too big go back through the rollers again. Fine flour that results is sold separately.
Bag the yellow grains

The finished semolina is pale yellow and gritty to the touch. It is packed for pasta factories, couscous makers and bakeries.

End of the lineSemolina Next it goes into pasta.

Worth repeating

Commercial dry pasta is made almost exclusively from durum semolina.
Semolina made from common wheat is beige and is called farina in the United States.
The word semolina comes from the Italian semolino, from semola, meaning coarse grains.