How Wet Pet Food Machines Differ from Dry Fish Feed Pellet Machines？

Jan 19, 2026

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Core Working Principle: External Humidification and Heating vs. Internal Frictional Heat Generation. The core principle of the wet dog food production machine is "external steam empowerment." During processing, saturated steam is injected into the extrusion chamber through an independent steam system, first uniformly wetting the powdered raw material to a moisture content of 18%-22%, while simultaneously raising the temperature to 80-100℃. Then, the twin-screw meshing rotation generates extrusion shear force, achieving gentle puffing and molding. The heat throughout the process mainly comes from steam, without relying on raw material friction. In contrast, the Dry Type floating fish feed pellet making machine has no steam humidification system. It relies entirely on the intense friction between the screw and the raw material, and between the raw material and the inner wall of the barrel, to generate heat. This raises the temperature inside the extrusion chamber to 120-160℃ and the pressure to 3-6MPa. The raw material expands instantaneously under high temperature and pressure. The heat and moisture both originate from the raw material itself and friction. The moisture content of the raw material during pretreatment must be strictly controlled at 10%-12%.

Core Process Flow: Multi-stage Control vs. Simplified Process. The wet dog food processing machine has a more complex process, requiring a full range of steps including "raw material pretreatment - steam humidification - gentle extrusion - puffing - drying and cooling - sieving and grading." Steam humidification is the core differentiating step, requiring precise control of steam pressure (0.4-0.6 MPa) and dosage to ensure uniform moisture content. The drying and cooling stage only requires light drying, reducing moisture to 12%-14%, resulting in lower energy consumption. The dry-type fish feed making machine has a relatively simpler process: "raw material pretreatment - high-temperature extrusion - puffing - drying and cooling - sieving and grading." It does not require steam humidification, but due to the high puffing temperature, the drying and cooling process requires significant cooling and dehumidification, leading to higher energy consumption. Furthermore, wet puffing machines can control the puffing effect through both steam dosage and screw speed, while dry puffing machines mainly rely on speed and raw material moisture control, resulting in lower control flexibility.

Differences arising from process characteristics: Gentle and controllable vs. highly efficient and intense. The steam humidification and low-temperature operation of wet fish feed extruders make the raw material extrusion process gentler, parameters easier to control, and pellet consistency stronger, reducing the likelihood of over- or under-expansion. In contrast, dry fish feed pellet extruders, with their frictional heating mode, are prone to localized overheating and uneven heat distribution, leading to pellet scorching, fluctuations in extrusion degree, and greater difficulty in parameter control. This difference in process also determines the equipment structure of the two: wet extruders require steam generation, delivery, and control systems, resulting in a more complex structure; dry extruders have a relatively simple structure, relying primarily on a high-strength screw and barrel to generate frictional heat.

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MIKIM's fish feed pellet production lines and supporting machinery offer excellent value for money. Not only are they affordable, eliminating middlemen markups and allowing small and medium-sized enterprises (SMEs) and fish farmers to purchase complete sets of equipment at reasonable costs, but they also boast exceptional efficiency. The fully automated process, from raw material crushing and precise ingredient mixing to extrusion pelleting and maturation, is completed in one continuous flow. This results in high starch gelatinization rates and uniform pellet formation, significantly improving production efficiency and feed quality, truly achieving "low cost, high output." Choosing a MIKIM fish feed pellet production line means enjoying comprehensive pre-sales and after-sales service, including 24-hour online customer support, a one-year warranty on the entire machine, professional on-site installation, commissioning, and maintenance, and a stable supply of spare parts. Customers can buy with confidence and use with peace of mind, with both excellent value and service quality!!!

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