Dry type fish food extruder line quality control techniques

A good formula requires good operation to translate into good feed. Aquatic feed formulations demand extremely high precision; even minor deviations in ingredient mixing can lead to stunted growth and weakened immunity in fish and shrimp.

The core techniques for operating a dry-type fish meal extruder line are precise weighing and sequential feeding. When using a fully automated electronic feeding system, the scale accuracy must be calibrated in advance to ensure the weighing error is controlled within ±0.1%. Calibration should be performed daily before startup using standard weights. The feeding sequence should follow the principle of "large to small, heavy to light." First, add bulk ingredients such as corn and soybean meal, then add high-protein ingredients such as fish meal and shrimp meal, and finally add premixes, vitamins, minerals, and other trace components to avoid trace components adhering to the inner wall of the equipment and causing loss. For additives used in very small quantities (e.g., less than 100g per ton of feed), a "pre-dilution" technique should be used. First, mix and dilute with a small amount of bran before adding to the mixer to ensure even distribution. The entire ingredient preparation process must be recorded, and ingredient data for each batch of feed must be retained for quality traceability.

The key to successful mixing at the animal food extruder line lies in "controlled time and speed, and uniform distribution." A twin-shaft paddle mixer should be used, with mixing time controlled at 4-5 minutes. Too short a mixing time will result in uneven composition, while too long a time will cause raw material grading. The mixer's load should be controlled at 60%-80% of its effective volume. Insufficient load will lead to incomplete mixing, while excessive load will prevent the raw materials from being properly agitated. A sampling point should be set at the mixer's outlet during operation. Samples should be taken from each batch to test the mixing uniformity using chloride ion titration. The coefficient of variation should be less than 7%. If the mixing uniformity does not meet the standard, the wear of the mixer paddles should be checked, and the mixing time or load should be adjusted.

Quality control requires "full-process testing and key point control." Upon raw material receipt, moisture and crude protein content must be tested. Fishmeal moisture content must be controlled below 10%, and crude protein content no less than 60%. Corn moisture content must be controlled below 14% to prevent feed spoilage due to excessive moisture. After pelleting, the pellets' soaking resistance, hardness, and moisture content must be tested. Soaking resistance is tested using the "static water immersion method," placing the pellets in 25℃ clean water and recording the disintegration time. Shrimp feed must take more than 40 minutes, and fish feed more than 30 minutes. Pellet hardness is tested using a hardness tester, controlled between 20-30N. Insufficient hardness leads to easy disintegration, while excessive hardness affects digestibility. Finished feed must be tested for microbial indicators. Total bacterial count must be controlled below 1×10⁴ CFU/g, and mold count below 500 CFU/g to prevent disease in fish and shrimp due to excessive microbial levels.

Establishing a "batch traceability system" is a crucial quality control technique. Each batch of feed is labeled with a production number, recording information such as raw material source, ingredient data, test results, and production personnel. In case of quality problems, the cause can be quickly traced and remedial measures taken. At the same time, we regularly collect feedback from aquaculture customers and adjust production operation parameters according to the growth of fish and shrimp, forming a closed-loop management of "production-feedback-optimization".

About Us

Customer visit

Certificate of Honor