Pasta extrusion process

Extruded food products such as pasta, snacks and ready to eat cereals differ from bakery products in the way their texture is formed.

In order to give the pasta its desired shape, the dough in its plastic state must be forced through an appropriate die relatively high pressure.

In the case of continuous extrusion presses, this pressure is generated by a screw. The ingredient are fed into a continuous high capacity extruder that is equipped with a variety of dies to produce having different shapes and appearance.

The shape of the holes in the die governs the shape of the pasta. For spaghetti, the die has round holes; for macaroni wheels, the die pushes the pasta. Leaving a large hole in the middle and gaps left by the spokes. 

When the extruded pasta reaches the right length, it is cut with sharp blades that rotate beneath the die.

Pasta extruder barrel are equipped with a water cooling jacket to dissipate the heat generated during the extrusion process and to help maintain a constant extrusion temperature around 35-50 °C to avoid gluten damage.

Most pasta shapes can be classified into two groups: long goods and short goods. The most familiar type of long goods is spaghetti which may have diameter ranging from 1.5 to 2.5 mm. Hollow extruded goods commonly referred to as macaroni, come in various lengths an forms.
Pasta extrusion process