The legume has various applications depending on the containing component and its type. The low protein type suits for animal food grown, raw material for bio-ethanol, and ingredients for confections. The high protein type suits protein enhancers and baby food, and recently it is popular for fish food as an alternative to animal protein. The switching from animal origin to vegetable origin fits with the trend of environmentally friendly and anxiety to the hazardous substance acquired through the food chain. However, protein content of vegetable origin is generally smaller than animal origin. The low protein content may lead poor growth of animals and fishes because of their limited food intake. Therefore, the high protein feed is required for growing fishes and animals.
In general, when grinding the raw materials of vegetable origin, such as legumes, the particle sizes of protein and starch are tend to be different. Using this characteristic, our milling and classification system can be used to separate materials of high protein content and high starch content.
In legumes, the size of the starch particles is generally in the range of several microns to several tens of microns. Protein particles on the other hand a generally smaller than this so separating the components based on particle size is possible. Protein particles tend to adhere to starch particles so when removing starch particles, protein particles tend to be removed together with the starch particles. By mechanically separating these attached protein particles, high protein content product can be obtained. This is method is called protein shift.
System and example
The following process are required for this system
• Milling of endosperm to break out the protein and starch
• Separation of protein attached to the starch particles
• Classification of coarse (low protein content) particles and fine
(high protein content) particles.
Hosokawa supplies two systems for this application, a standard type system and a high performance type system. For requirements of high yield or high protein content, the high performance system is used. The standard system uses the ACM Pulverizer as the mill and the Micron Separator MS-H as the classifier. The High performance system uses the ACM Pulverizer as the mill and the Turboplex ATP as the classifier.