Pre cooked flours are used worldwide to nourish young children and are also consumed in many countries as a basic ingredient for regional dishes, such as porridge or soups. Clextral twin-screw cooking extrusion lines are particularly well suited to manufacture these flours. They enable precise cooking of raw materials and allow manufacturers to process a wide range of recipes ensuring consistent quality and optimum food safety.
How are pre cooked flours produced ?
Cereals or cereal based products are fed into the twin-screw extruder using a gravimetric or volumetric feeder. Water, injected directly into the twin screw extruder, is mixed with the powder, thus forming a « paste ». The flour paste is subjected to thermo-mechanical treatment in the baby food production line, at a controlled speed in keeping with thermally controlled parameters. The composition and the speed of the screw are important factors in the thermo-mechanical process. Accurate temperature control is achieved through an internal cooling system in each barrel module according to the temperature profile selected by the operator.
Residence time is also controlled in the configuration of the machine through the number of barrel modules, calibration of the die and product flow. This means that an ideal transformed starchy base is produced thus proving an easily rehydrated product with the suitable viscosity.
The hot paste (> 100 ° C) is forced through the extrusion die: the pressure difference between the inlet and the outlet determines the features of the expanded product. The configuration of extrusion parameters means that the cooking characteristics and texture of the product are precisely controlled. The cereal based product is cut at the die exit, and undergoes further drying before grinding, resulting in optimized elements that facilitate future rehydration to make the consumable product.
A perfectly controlled technology
Clextral systems offer many advantages:
- Precise control of all parameters to produce high quality products
- Reduced production costs compared to traditional technologies (drum drying) with energy and water savings
- Compact design, reduced footprint
- Food safety and traceability