Features of Aquafeed

  When choosing aquafeed production equipment, you must first understand the many characteristics of aquafeed:

     1. Small particle size. Due to the short digestive tract and related physiological characteristics of aquatic animals, in order to speed up digestion and absorption, the crushed particle size of aquatic feed should be smaller than that of livestock and poultry feed. For example, in the production of eel and shrimp feed, the particle size should reach 80 to 120 mesh.

     2. High protein content and low carbohydrate content. The protein content of livestock and poultry feeds is generally less than 20%, while the protein content of aquatic animal feeds is mostly 30% to 40%, and the protein content of turtle and eel feeds is as high as 65% to 70%.

     3. The pellet feed has a compact structure, high cohesion and water resistance, and the shrimp feed requires the pellet feed to be stable in water for more than 2 hours.

     4. In the production of aquatic feed, cross-contamination is strictly prohibited. Some raw materials need to be treated aseptically. The selected equipment is easy to clean and has less residue. Especially when producing shrimp and eel feed, other types of feed should not be produced at the same time to prevent cross-contamination. .

To produce high-quality aquatic feed, we must rely on scientific and reasonable processing technology and combine it with advanced, reliable and stable processing machinery. In this regard, the choice of processing equipment is particularly critical.

Selection of particle conditioning and molding equipment

    However, for the production of aquatic feed, higher gelatinization degree and water stability are required, and conditioning conditions must be strengthened at this time. On the premise that the moisture and temperature are satisfied, the only way to do it is to prolong the conditioning time. The most common equipment is the multi-channel conditioner before granulation. Generally, there are three conditioners. Its structure is basically the same as that of the monotonic, and the conditioner with a lengthened double-layer jacket is used. The conditioner is used for curing before granulation, which can ensure that the bait is fully gelatinized and improve the water resistance of the bait. Usually, the stability in water can reach more than 2 hours. Due to the prolongation of the material conditioning time, the material and the steam can be fully and uniformly mixed, and starch gelatinization and protein denaturation occur at high temperatures. A variety of harmful bacteria, and the surface of the particles is smooth and not easy to be eroded by water, which not only improves the stability of the particles in water, but also improves the palatability and digestibility of the bait, ensuring a longer feeding time for fish and shrimp, and preventing water pollution. Therefore, in the production of aquatic feed, a multi-channel conditioner can be used to ensure a certain product quality.

In addition, since aquatic animals such as soft-shelled turtles, prawns, crabs, and minks have higher requirements for starch gelatinization and water resistance, stronger conditioning measures are required. The most used method is to add curing equipment after granulation, that is, to change the previous pellet bait to enter the cooler for cooling immediately after it is made, and add a post-curing device between the granulator and the cooler, so that the pellet bait is further insulated and fully cured. , to avoid the phenomenon of external cooked and endogenous granular bait, which can greatly increase the bioavailability of the bait. The optional equipment is a particle stabilizer, which is to heat the newly produced particles immediately, because the temperature of the particle bait can reach about 85 °C when it is released from the mold, so that the hot particles can be kept at high temperature and high humidity for a period of time, so that the The starch in the granular bait is fully gelatinized, the protein is fully denatured, especially the starch on the surface is completely gelatinized and hardened, which improves the water resistance. Another stable cooling combined machine includes two parts: stabilization and cooling. The stabilized particles are sent to the cooling part through the pendulum discharge mechanism. The cooling part adopts the principle of countercurrent cooling, that is, the direction of the cooling air flow is opposite to the direction of the material flow, so that the particles flow smoothly. to gradually cool down. For a feed factory that can only produce livestock and poultry feed, if it wants to produce special aquatic feed, and there is not enough space to add a curing device, only a multi-channel lengthened conditioner is used to strengthen the conditioning of the material before the preparation.

Selection of floating particle equipment

    Feed extrusion technology is mainly used in the production of special aquatic feed, pet feed and other animal feed. In addition to the advantages of general full-price pellet feed, extruded feed can improve the digestion and absorption rate of feeding animals, and can effectively prevent animal digestive tract diseases. Extruded feed is not only suitable for materials with high starch and fat content because of the gelatinization and gelatinization effect of starch, but also because of the high temperature and high pressure curing effect, the disinfection and sterilization effects are more obvious, and the applicability is strong. . It is precisely because of the advantages of puffing that more and more feed mills are beginning to puff aquafeed. At present, the main working principle of the extruder used in domestic feed factories is to treat powdery materials containing a certain amount of starch (more than 20%) through a conditioner, so that the moisture content of the material can reach 25% to 27%, and the temperature rises. to 80℃～100℃. The extruder consists of a feeding system, a transmission system, an extrusion system, a discharging die and an electrical control system. The quenched and tempered material enters the screw extrusion zone. Since the volume of the extrusion zone gradually decreases along the axis, the pressure on the material gradually increases, and the compression ratio can reach 4 to 10. The material is pushed by the screw extrusion, and accompanied by strong shear and friction, the pressure and temperature rise sharply. Under the action of high temperature and high pressure, the starch in the material can be basically completely gelatinized, and the protein is partially deformed. When the material is squeezed out of the die hole by a great pressure, the temperature and pressure drop sharply due to the sudden departure from the machine body and into the atmosphere. Under the combined action of the pressure difference and temperature difference, the volume of the feed expands rapidly, and the material flashes, that is, the water evaporates rapidly. , dehydration and solidification, and then through the customized discharge mold to achieve various shapes and structures required, the extruded pellet feed is made.