العربية
Indonesia
ไทย
Tiếng ViệtIn distant-water fishing operations, the freshness of fish will be lost in minutes after leaving the seawater. Fishermen have found that using seawater ice machine can cover the fish with ice as soon as they are landed, which is much faster than waiting for the freezer to refrigerate.
The key role of fast freshness lock
On Southeast Asian tuna fishing boats, the crew will put the freshly caught fish directly into the ice slurry tank and complete the surface cooling within five minutes. This rapid treatment can reduce the breakage of fish fibers and avoid the problem of loose meat caused by slow freezing in the freezer. Experienced captains will emphasize that when handling high-value fish, a ten-minute delay in ice application may reduce the auction price by 20%.
The secret to saving space on fishing boats
Fishing boat space is a precious resource. Traditional freezers not only occupy a fixed space, but also need to reserve cold air circulation channels, and the actual storage capacity of fish is limited.
The Chilean cod fishing team uses a dynamic ice-making method: the ice production of the industrial ice machine is adjusted according to the daily catch, and the crushed ice and fish are stacked alternately in layers. This method allows the same size cabin to hold 40% more catch, which is particularly suitable for the harvest period when the fish are dense. In addition, the gaps between the ice layers can reduce the squeeze damage of the fish body and keep the appearance intact.
Practical skills to reduce energy consumption
The fuel cost of diesel generators accounts for about 35% of the total expenditure of fishing vessels. Freezers require continuous electricity to maintain low temperatures. When operating in tropical waters, the compressor load will increase by more than 50%. Trawlers operating in the Indian Ocean convert the heat energy emitted by the main engine into marine ice maker power by modifying the waste heat recovery system, saving about 200 liters of diesel per day.
The specific operation is: add a heat exchanger to the engine exhaust pipe, use the waste heat to heat the refrigerant, and cooperate with seawater cooling to achieve zero-power consumption ice making. This method can also continue to produce ice during low fishing hours at night.
Emergency plan for dealing with emergencies
Offshore equipment failure is a common risk. In 2022, a fishing boat operating in the eastern Pacific Ocean had its freezer shut down due to a generator failure, and the entire hold of fish spoiled within six hours. For fishing boats using seawater ice machine, even if the main engine is completely shut down, the stored ice can still maintain effective cooling for more than ten hours.
Experienced crew members will reserve 10% of the ice as an emergency reserve, covering the top layer of the fish pile to form an insulation layer. At the same time, regularly checking the tightness of the ice machine drive belt can reduce the probability of sudden jamming.
Preservation techniques to increase the value of fish
- Fish grading: Store fish of different sizes in ice separately to avoid large fish crushing small fish. Fishermen in the Marshall Islands use plastic baskets of different colors to distinguish grades and improve dock unloading efficiency.
- Key parts protection: Fish gills and abdominal cavity are the fastest corrupting areas. Alaska salmon handlers will fill the gills with crushed ice produced by flaked ice machines to delay the odor caused by the corruption of internal organs.
- Ice layer renewal rhythm: Check the melting of the ice layer every eight hours, and give priority to replenishing the melting layer in direct contact with the fish body. When operating in the equatorial area, a small amount of seaweed gel can be added to the ice to slow down the melting rate.
- Odor isolation measures: Pack squid and other seafood with strong odors separately, and separate them from fish by at least two layers of ice to prevent flavor cross-contamination.
Equipment selection and maintenance suggestions
When purchasing ice making equipment, it is recommended to focus on three parts: the wear resistance of the ice-making blade, the corrosion resistance of the brine pump, and the self-cleaning function of the condenser.
Monthly maintenance of flake ice machine should include three steps: first rinse the salt crystals with fresh water, then soak the ice delivery pipeline in edible vinegar for ten minutes to sterilize, and finally add food-grade lubricating oil to the bearing part. If the blade is stuck, stop the machine immediately to remove the entangled seaweed or fish scale fragments to avoid motor burnout.
Long-term cost comparison analysis
Take a medium-sized trawler as an example, and compare the operating costs for a five-year period:
Freezer solution: initial purchase cost of US$80,000, annual average electricity cost of US$32,000, and fish loss rate of about 12%.
Seawater ice machine solution: equipment investment of US$95,000, annual average fuel cost of US$18,000, and fish loss rate controlled within 6%.
After five years, the comprehensive cost of the ice machine unit is 21% lower, and the residual value of second-hand equipment is 15% higher than that of the freezer. The financial report of a Norwegian fishing company shows that after switching to seawater ice machine, the export unit price of its frozen fish products has increased by 8%.
Common misunderstandings reminders
- Over-reliance on ice volume: Some crew members think that the thicker the ice layer, the better. In fact, ice layers exceeding 15 cm will hinder cold air convection and accelerate the temperature rise of the bottom fish body.
- Wrong use of freshwater ice: Freshwater ice has a higher melting point and will dilute the natural salt protective layer on the surface of the fish body. Freshwater ice can be used in an emergency, but it needs to be replaced every four hours.
- Ignoring drainage design: Timely drainage of ice-water mixture is crucial. An Indonesian fishing boat once had water accumulation in the cabin due to a blockage in the drainage outlet, causing 300 kg of fish to be soaked and spoiled. It is recommended to choose an automatic drainage ice machine to solve this problem.
