Expanded aquaculture feed is a new type of aquatic feed that is gradually accepted and promoted by the majority of farmers in response to the benign development needs of global fish farming feeds towards low pollution, low waste, high efficiency and high conversion. In recent years, China's aquatic feed production has grown rapidly, and shrimp and precious special aquatic feeds have developed rapidly. Among these special aquafeeds, extruded puffed pellets have become the main product form. Since the production lines of extruded extruded aquatic feeds are mostly new in recent years, especially the control technology of the operating conditions of the extrusion extruder is not perfect, many domestic feed manufacturers are constantly exploring the processing technology and production characteristics of the expanded aquatic feed. And the development stage, so the processing quality of the feed products produced by various manufacturers will have a big difference. Even the quality of the same variety of products produced by the same manufacturer in different batches may fluctuate significantly. There is no guarantee that the physical characteristics will be stable. After years of production practice experience. It is believed that the bulking materials generally have the following defects in the processing: 1) Uneven particle size and uneven length; 2) There are many stomata pores; 3) Particle deformation; 4) insufficient particle hardness; 5) The particle water resistance is not good, and the viscoelasticity is poor; 6) The grain incision is not neat and oblique; 7) granule expansion is not high; 8) The particles have submerged water; 9) The granules are big and small; 10) The particles form a double-cut concave ; 11) granules with tail; 12) Peeling the surface of the particles. After many years of practical experience in production, the author summarizes some problems that often occur in the processing of expanded materials, and proposes corresponding solutions. 1, uneven particle size, uneven length Feed pellets vary in size and length, which not only affects the aesthetics of the feed, but also affects the inconsistency of palatability and water resistance time, resulting in unnecessary waste. In addition, it will also become an excuse for farmers to complain. 2, particle stomata and more There are many stomata in the granules, and the rough surface not only affects the appearance of the feed, but also the feed is easily broken into powder during transportation, causing unnecessary waste. It is not easy to sink during the feeding process and has a long floating time. 3, particle deformation is not round The deformation of the particles may be due to deformation of the die holes or due to excessive moisture, which is squeezed and deformed during the conveyance process. Therefore, it is better to use pneumatic conveying for the high-temperature puffed feed just emerging from the mold, so that not only the surface of the granule can be quickly formed into a layer of colloidal coating, the granules can be broken, and the shape of the granule can be rounded. However, during the pneumatic transportation, the moisture of the particles is very heavy and needs to be dried as soon as possible. The particle deformation is not far, resulting in uneven particle size, which affects its palatability. 4, the particle hardness is not enough Feed hardness is the resistance of the feed to deformation caused by external pressure. Insufficient feed hardness can cause deformation of the feed during handling and thus affect the appearance of the feed. It causes the feed to dissolve in the water before it is eaten. It may also be a large amount of water. The feed is not easy to store and is prone to mildew. 5, particle water resistance is not good, poor viscoelasticity The water resistance of the feed refers to the ability of the feed to resist corrosion in water, and is usually expressed as the loss rate of the feed in water under specified conditions. Poor water resistance of the feed can cause the feed to dissolve in the water before it is eaten, causing unnecessary waste and contaminating the water. Poor viscoelasticity results in poor palatability of the feed. 6, the grain incision is not neat, oblique The produced feed should be cut into neatly sized granules, irregular and deformed granules, affecting the appearance of the feed. Generally, the adjustment of the incision and the cutter is unreasonable, and it may be due to the large amount of material being fed. 7, the grain expansion rate is not high The feed is too hard and the water is dissolved for too long, which affects its palatability and digestibility. High levels of lipid compounds reduce swelling, and when the fat content is between 17 and 22%, the product does not puff or expand. The low puffing rate of the particles will cause the feed to float in the water for a short period of time and easily sink into the bottom of the water, causing unnecessary waste. 8, the particles have submerged water phenomenon The particles have submerged water, which may be due to too low expansion coefficient and excessive material ratio. If some granular floating materials appear to be submerged, one is to cause unnecessary waste, and the other is that it is difficult to observe the situation of fish eating. 9, a large head and a small The feed pellets are large and small, affecting the appearance of the feed, easily causing feed breakage, increasing the chalking rate and reducing the palatability. 10, the particles form a double-cut concave This is usually the case with a concave double-faceted granule, uneven feed puffing, and an unreasonable ratio of water to steam. Irregular granules not only affect the appearance and quality of the feed, but also cause more feed powder and affect its palatability. 11, granules with tail The granules have tails for a variety of reasons, mainly the problem of cutting knives. Feed pellets with tails not only affect the appearance and quality of the feed, but also lead to more feed powder. 12, particle surface peeling The surface of the feed is very easy to produce dust during transportation. The surface peeling may be related to the lack of moisture in the expansion, and may also be affected by the mold and the cutter in the processing process. It not only affects the appearance and quality of the feed, but also leads to more feed powder. Excessive water addition, the formed material is too soft, easy to deform, generally should be added in 25 to 30% of moisture. Surface peeling also affects the water resistance of the feed. The farmers are skeptical about the quality of the products. Ceiling Diffusers,Ceiling Vent Diffuser,Ceiling Ventilation Grill,Ceiling Diffusers And Grilles Guangzhou Jointair Co., Ltd. , https://www.nbjointair.com