(1) Eliminate anti-nutritional factors and improve the digestion and absorption rate of feed. There are many anti-nutritional factors in feed raw materials, such as saponins, gossypol, trypsin inhibitors, etc. in rapeseed, soybean meal and cottonseed meal. Under certain moisture and temperature, these anti-nutritional factors Part of the activity is gradually lost during the puffing process, thereby reducing the damage to the endogenous digestive enzymes of the animal body, improving the digestion and absorption rate of the feed, and reducing excretion.

(2) High-temperature disinfection to ensure the safety and hygiene of feeding materials. The maximum temperature of extrusion can reach about 150 °C, and the action time of the raw materials at high temperature is very short, about 8 seconds. After the raw materials are extruded under high temperature and high pressure, various microorganisms, insect eggs and pathogenic bacteria in the feed can be killed, the quality of the feed can be improved, and the digestive tract diseases of animals can be reduced.

(3) Improve the palatability and flavor of the product.

The puffed product has a loose, porous and crisp structure, and has good palatability and flavor. The template can be made into different shapes of die holes, so different shapes of extruded pellets that animals like can be pressed. It can also produce special high-fat feed, such as Atlantic salmon, rainbow trout and other cultured species, which have a high amount of fat added, some as high as 30%.

(4) Improve the gelatinization degree of starch, which is beneficial to the digestion and absorption of starch.

Studies have found that the degree of gelatinization of starch in the feed can be increased from 13 to 13 by extrusion. 58% increased to 81.55%, the higher the degree of puffing, the easier it is to be fully utilized by enzymes. Vegetable raw materials are processed under high temperature and high pressure during the puffing process to make starch gelatinization and protein organization, which is beneficial to animal digestion and absorption, and improves the digestibility and utilization rate of the raw materials. The digestibility of aquatic products can be increased by 10%~35% after puffing.

(5) Improve the digestion and absorption rate of word materials. The digestive tract of fish is short, and most of them are stomachless fish, so the finer the food, the higher the digestion and absorption rate. The extruding process requires finer crushing of raw materials, thereby improving the digestion and absorption of fish. At present, the crushing fineness of raw materials for high-grade extruded aquatic products such as seawater fish in the production reaches 95% and exceeds 80 mesh, while the crushing fineness of raw materials for extruded raw materials of common species such as grass carp, tilapia and fork-tailed pomfret also reaches 95% and exceeds 60 mesh.

(6) The puffed material is good for preservation and breeding management. Due to high temperature and high pressure puffing and drying treatment, the moisture content of the finished product is generally required to be less than 10.0%. The packaging generally adopts the method of sealing the inner and outer bags separately, so under the same conditions, the shelf life is longer and it is convenient for storage.

(7) The extruded feed has strong water stability, does not collapse within 16 to 32 hours, and has little pollution to water quality.

The loose and porous extruded floating material floats on the water surface, which is easy to observe the feeding and growth of fish, which is beneficial to scientific management; while the high-fat and dense extruded submerged material has a stability in water of more than 16 hours, ensuring fish Feed adequately and reduce waste.