• Improve feed utilization: The high temperature, high pressure and high shear force during the puffing process increase the degree of starch gelatinization, destroy and soften the cell wall of the fiber structure, and release partially surrounded and combined digestible substances, while fat Penetrating from the inside of the particles to the surface gives the feed a special flavor and improves palatability, thus increasing the feeding rate.
• Reduce environmental pollution: Extruded floating fish feed has good stability in water, which can reduce the dissolution and precipitation loss of feed nutrients in water and reduce water pollution.
• Reduce the occurrence of diseases: The high temperature, high humidity and high pressure during the puffing process can kill most harmful microorganisms, helping to maintain water quality and reduce adverse environmental factors in aquaculture, while reducing the mortality of aquatic animals.
• Increase breeding density: The use of extruded compound feed can reduce the feed coefficient and greatly reduce the amount of residual bait and excrement discharged into the water body, making it possible to significantly increase the breeding density.
• Extend the storage period of feed: Extrusion and puffing processing improves the stability of raw materials by reducing bacterial content and oxidation.
• Increase palatability and digestibility: The expanded feed becomes a loose and disordered structure. This change provides a larger contact area for enzymes, which is conducive to the contact of starch chains, peptide chains and digestive enzymes, and is conducive to the digestion of feed. absorption, thus improving the digestibility of feed.
• Improve fiber solubility: Extrusion and puffing can greatly reduce the crude fiber content in feed and improve feed utilization.
Disadvantages of extruder granulation:
• Destruction of vitamins: Friction between pressure, temperature, moisture in the environment and feed can lead to the loss of vitamins in the feed, especially vitamin A, vitamin D and folic acid.
• Inhibition of enzyme preparations: High temperatures during the puffing process may gradually and completely lose the activity of enzyme preparations.
• Destroy amino acids and proteins: Under high temperature conditions, puffing will cause Maillard reaction between some reducing sugars in the raw materials and free amino acids, reducing the utilization of some proteins.
• Higher production costs: The feed expansion process is more complex than the general pellet feed process. The expansion process equipment is expensive, has high power consumption, and has low output, resulting in high costs.
Advantages of granulating machine:
• High production efficiency: The granulator can quickly turn raw materials into granular products of the required shape, improving production efficiency.
• Uniform particle size: During the granulation process, the material is subjected to shear force and extrusion force, making the particle size distribution of the finished particles uniform.
• Convenient operation: The granulator has a simple structure, is convenient to operate, and is easy to control and adjust.
• Wide scope of application: The granulator can be used for granulating a variety of materials, including granular pharmaceuticals, chemical raw materials, food, etc.
Disadvantages of granulator granulation:
• Possible destruction of vitamins and enzyme preparations: High temperatures and pressure during granulation may destroy the activity of vitamins and enzyme preparations.
• Possible damage to amino acids and proteins: Under high temperature conditions, granulation may cause Maillard reactions between some reducing sugars in the raw materials and free amino acids, reducing the utilization of some proteins.
• The granulated material is dry and wet: the mixing speed and mixing time of the granulator or the shearing speed and shearing time of the shear are too low to disperse the binder or wetting agent quickly and evenly. There will be uneven mixing and granulation of materials.
• Particles form agglomerates and agglomerate: The amount of added binder or wetting agent is too high and the addition rate is fast. It is recommended to appropriately reduce the amount of binder or wetting agent and control the addition rate.
In summary, extruder granulation and granulator granulation each have their own unique advantages and disadvantages, and the selection needs to be determined based on specific application needs and conditions.