Fish Feed Machine Knowleagde

Puffing processing is a new technology of feed processing. The puffing of feed in the extrusion cavity is actually a high-temperature transient process: the mixture is at high temperature (110-200 ℃), high pressure (25-lOOkg/cm2), and high shear In the environment of high strength and high moisture (10%-20% or even 30%), a kind of bulky and porous feed is formed through continuous mixing, conditioning, heating and pressurization, maturation, extrusion die holes and sudden pressure reduction.

What are the advantages of extruded feed?　
1. Improve the utilization rate of feed
The heat, humidity, pressure and various mechanical effects during the expansion process break the 1,4-glycosidic bonds in the starch molecule to produce low molecular weight products such as glucose, maltose, maltotriose and maltodextrin. The expansion process can make starch paste The degree of chemistry is increased, the cell wall of the fiber structure is destroyed and softened, and part of the enclosed and bound digestible substances are released. At the same time, the fat penetrates from the inside of the pellet to the surface, giving the feed a special flavor, improving palatability, and thus feeding rate improve. In addition, the protein in vegetable protein feed can inactivate certain protease inhibitors such as antitrypsin and urease after moderate heat treatment, and destroy the hydrogen bonds and other secondary bonds in the protein, causing the original polypeptide chain The spatial conformation changes, resulting in protein denaturation, the denatured protein molecules become fibrous, the peptide chain stretches loosely, the molecular surface area increases, the flow is blocked, and the contact with the enzymes in the animal body is increased, which is conducive to the digestion and absorption of aquatic animals. Improve the digestibility and utilization rate of nutrients by 10%-35%.

2. Reduce environmental pollution
Expanded floating fish feed has good stability in water. The feed pellets processed by extrusion and expansion rely on the starch gelatinization and protein organization in the feed to make the product have a certain adhesion or binding force. Its stability is generally more than 12h, and the longest can reach 36h, so it can Reduce the dissolution and precipitation loss of feed nutrients in the water. Data shows that the general use of extruded floating fish feed can save 5-10% compared to powder or pellet feed, and can avoid feed residues in the water and reduce water pollution.

3. Reduce the occurrence of diseases
Feed ingredients often contain harmful microorganisms, such as aerobic organisms, neutrophils, Escherichia coli, molds, salmonella, etc. The content of animal feed ingredients is relatively high. The high temperature, high humidity, and high pressure of puffing can kill most harmful microorganisms. According to data, the number of Escherichia coli per gram of raw material is up to 10,000, and only less than 10 are left after expansion. Salmonella can basically be killed after being expanded at a high temperature above 85 ℃, which helps to maintain water quality and reduce Unfavorable environmental factors in aquaculture, while reducing the mortality of aquatic animals.

4. Increase breeding density
Under artificial breeding conditions, the increase in breeding density means that the higher the rate of return for farmers. When the aquaculture density per unit of water is increased, the space for fish in the aquaculture water is reduced, and the requirements for water quality will be much higher than the level of the natural environment. Because the use of extruded compound feed can reduce the feed coefficient and greatly reduce the residual bait and excrement discharged into the water body, it is possible to greatly increase the breeding density.

5. Extend feed storage period
Extrusion processing reduces the bacterial content and oxidation, thereby improving the stability of the raw materials. When the extruded product is dried and cooled, the feed water activity (AW) has been reduced to 0.6 or even 0.4, which is equivalent to a moisture content of 8% to 10%, which better improves the storage stability of the feed.

6. Convenient feeding management
Aquatic extruded feed can be suspended on the surface of the water (water) for a long time. There is no need to set up a special feeding table when feeding, just feed at a fixed point. Fish need to float up to the surface of the water when they eat, so they can directly observe the fish's eating situation, adjust the feeding amount in time, and understand the growth and health of the fish in time. Therefore, the use of aquatic extruded feed is helpful for scientific feeding and management, which not only saves a lot of time, but also improves labor productivity.

7. can meet the needs of animals with different feeding habits
Extruded feed can be divided into three types according to the different processing technology: floatability, slow sedimentation, and rapid sedimentation. At present, about 80% of fish feed is sinking feed. For example, shrimp, salmon, salmon, and yellowtail tuna all like sinking feed, while catfish, tilapia, eel, and most fish juveniles like floating feed. , Catfish and tilapia have the same preference for sinking feed and floating feed. In addition, extruded feed can also meet some special requirements, such as low-moisture feed and high-fiber feed