Advantages of Extruded Aqua feed Pellet
The capability of an fish feed extrusionÂ enhances the feed manufacturerâ€™s flexibility to produce fish feed pellets for shrimp, crab, eel, catfish, carp, frogs and etc..
2.High starch gelatinization
Feed material goes through the aqua fish feed extrusion process of HTST, starch gelatinization degree increase can reach 80-99% for aquatic animals easily digest.
3.Better digestion and absorption
Pellets can breakdown quickly in the stomach of fish loses nutrients (during regurgitation), which contributes to better absorb nutrients.
4.Improved water stability
The Aqua fish feed extrusion are more resistant to disintegration in water and a floating feed allows the fish farmer to observe the condition of the fish and the amount of feed consumed.
5. Water absorption
Extrusion moisture content during aqua fish feed extrusion processÂ can be controlled over a wide range, which helps to increase the water stability of the final feed. These pellets absorb more water, retains shapes for longer time and results in reduced losses of nutrients. It benefits pellet technical qualities and fish health.
6.Convenient for density control
It is entirely feasible for an extruder forÂ Aqua fish feed extrusion, sinking feed and slow sinking feed by density control; that is more conducive to different fish species.
fish feed extrusion process Process
Extrusion, including dry extrusion and wet extrusion, is the aqua fish feed extrusion process where the raw material is pushed forward in the barrel by means of screws and pressed through the die at the end of barrel. The general extrusion process involves a high temperature over a short time. Temperature higher than 100â„ƒ is needed in order to achieve expansion of the feed as it leaves the die.
The high temperature in dry extrusion is acquired through dissipation of mechanical energy from heated surfaces such as barrel and screw surface, or generated by shear forces between wall and material and screw and material.
For wet extrusion, the temperature is achieved through preconditioning and steam injection. At the same time the material also undergoes relatively high pressure. The pressure difference in the interior of extruder and the external environment will cause the extrusion of the aquatic feed.
Dry Type and Wet Type Extruder
Dry type extruder is the type of fish feed extrusion machine that does not require a steam boiler for heat or steam injection or jacket heating, and all product heating is accomplished by mechanical friction force. Without utilizing preconditioning, dry extrusion employs lower moisture levels. Therefore it is suitable for processing low moisture and high fat feed material.
While wet type extruder is a piece of more complex equipment with precision metering systems for steam or water injection into the conditioner and/or the extruder barrel. Preconditioning is a very important step in wet aqua fish feed extrusion process for chemical or physical reactions to take place.
The heart of the extruder machine working is: preconditioning, cooking and die shaping. High temperature and high pressure process can kill the salmonellosis and bacterial infections and also makes the pellets easily to digest.