19 February 2020
The article describes the machines that make up the mill, in particular the debranner.
In the previous articles we have already talked about the rollermill, the plansichter and the purifier.
In recent years, the debranning pre-milling process has become increasingly popular among milling operators. It improves the milling performance of cereals. The process can be considered as one of the major and substantial innovations of the milling process.
The debranner is a turning point in improving the health aspect of cereals. It is placed at the beginning of the traditional milling process to eliminate the cortical part, keeping the grain intact.
Most of the bran is removed by a progressive and controlled surface abrasive action. This allows to increase the extraction performance compared to the standards, to improve the cleaning of the semolina and to increase the production capacity.
The characteristics of the debranner
- Decortications chamber;
- Abrasive stones;
- Vertical rotating shaft;
- Perforated shells;
- Impulsion fan.
The grain, wet and conditioned, enters the machine from the top. It is distributed uniformly and automatically, in the decortications chamber.
Inside, special conveyors arrange to place the grain in relation to the abrasive stones to uniformly decorticate it.
The bran is expelled through the perforated shells surrounding the rotor (vertical rotating shaft). It comes out thanks to the aspiration transport to which the machine is connected and to the impulsion fan provided by the machine.
The degree of decortication depends on the amount of cereal in the machine and also on the time the cereal is kept. These are determined by an electronic software that control the exit valve.
The preventive removal of the tegumental layers by abrasion and friction actions conducted on the grain makes it possible to greatly simplify the grinding diagram by reducing machines and grinding passages.
The advantages of the debranner
In general, husking may improve the hygiene and health characteristics of durum wheat by increasing the safety of the use of finished products. In addition, a useful tool for nutritional and health purposes, to enrich the raw material with bioactive compounds such as fibers and antioxidants.
The debranning process is able to:
- Increase the milling yield;
- Reduce α-amylase activity in flour (germinated grains);
- Obtain by-products with bioactive components;
- Obtain safer flour from the hygienic-sanitary point of view (less presence of phytopharmaceutical residues, heavy metals and mycotoxins);
- Improve the quality of flours (less stains, moulds, bacteria, mycotoxins and ash).
Contaminated caryopsis
It has been studied the debranning treatment applied to wheat caryopsis with a level of contamination higher than the legal limits and different debranning times have been tested.
The results showed the effectiveness of this treatment in reducing the level of DON (deoxynivalenol, a mycotoxin) in the shelled grain and a progressive concentration of mycotoxin in the husking waste.
The first debranner of Molitecnica Sud
As far as the company reality of Molitecnica Sud is concerned, the first debranner built in our factory dates back to 2012. Today we are able to design and build not only high quality shelling machines entirely produced in Italy, but also complete grinding plants suitable for every need. To learn more about milling plants click here.
