Fishermen harvest almost 100 million tons of fish per year. An additional 50 million tons come from commercial fisheries. While the exact number is unknown, it is estimated that up to 2.7 trillion fish are caught and consumed each year. This number accounts for about 16% of the total protein consumption globally. Fish are an important food source because of their central role in the diets of many people and their nutritional content, including essential fatty acids that promote heart and brain health.
The vast majority of the global fish supply comes from industrial fishing, is an enormous industry that employs over 500 million individuals each year. It is done by large corporations and small, family-owned businesses. Commercial fisherman must pursue their catch far into the ocean, often facing adverse conditions and real danger, including on-board injury, vessel disasters and falling overboard. In addition to the physical dangers a commercial fisherman may encounter, they also face great financial risk. They must maintain expensive vessels and equipment but there is no guarantee their investments and efforts will produce a profitable haul.
It is important that each catch is processed efficiently in order to preserve the quality and quantity of fish that can be brought to market. Semco manufactures cooling and storage products for industrial fisherman that can enable them to maximize their profits by reducing the number of fish that are lost to spoilage and contamination. Our products include ice banks and storage bins, slush cooling systems, hydrocoolers, and fully custom-designed systems and can be used for transporting both live and deceased fish.
Processing Live Fish
Once a catch is hauled in, it goes through several processes on the way to market. Fresh fish deteriorates quickly and must be handled appropriately in order to maintain its value. Many companies choose to keep fish alive until they can be delivered to market.
- Fish should be stored in clean water. Each catch must be sorted carefully. Healthy fish may be placed in a container of clean water, while dead or diseased fish must be thrown out. It is important to remove unhealthy fish so they do not contaminate the water or the healthy individuals.
- Fish shouldn’t be fed. This makes them less active, decreasing their metabolic rate and extending the amount of time they can occupy tanks before their respiration and waste products bring the pH to unhealthy levels.
- The water should be cool. The temperature should be lowered gradually to avoid shocking or stressing the catch. Optimum temperatures depend on the type of fish and time of year. Cooler water decreases the animal’s activity level, increasing the time and distance they can be transported and enabling them to be packed more densely in the water. Careful temperature control can bring fish to a state of near hibernation, greatly reducing the rate of fish that die en route. Low death rates and high density are crucial for a fisherman to reap the greatest profits from the catch that they risked so much for.
Many commercial fisheries utilize holding basins, fish yards or floating cages that are equipped with water filtration and oxygen, circulation and temperature controls to maximize the amount of time that live fish can survive in transport and to increase the number of fish that can be transported in a single container.
Transporting Frozen Fish
While many species of fish are hardy enough to tolerate live transportation, even from one country to another, it is not a viable option for the bulk of the fish harvested worldwide. Captured fish have been preserved with ice for thousands of years to maintain their freshness and quality from the water to the market.
- Cold temperatures reduce spoilage and disease. Fish should be cooled to about 0°C. This prevents spoilage and reduces the growth of pathogenic microorganisms that can cause illness and disease. Contaminated seafood poses a great health and safety risk, and buyers will turn away a catch that seems questionable. Some fish are gutted and sectioned before they are put on ice while others are frozen whole. In either case it is important that the product be frozen as quickly as possible to prevent disease and decay, and that it remain frozen until it has reached the consumer.
- Ice keeps fish moist. By submerging fish into a slurry of ice and water the fish will chill more quickly, and the melted ice will keep the skin fresh and hydrated. Dehydration can cause weight loss. As most fish are sold by weight, this decreases the profits a fisherman can collect. This treatment also prevents the growth of pathogenic bacteria.
- Ice has a large cooling capacity. A small amount of ice can cool a larger amount of fish than most other cooling methods. Insulated containers are important for keeping ice from melting, which can make it less efficient. Ice maintains a constant temperature, ensuring the catch is uniformly chilled.
- Ice is convenient. It is portable and can be distributed evenly around fish. It is easy to store, transport and use. Various sources of water can be used to generate ice, although the source should be tested to ensure it will not contaminate the product. When utilized correctly it is a cheap and easy way to preserve a catch.
In order to maintain the quality of fish transported to market and maximize the quantity that can be sold, industrial fishermen must have the appropriate equipment to process their catch quickly and to transport live or frozen fish long distances. Semco manufactures and installs equipment that can enable commercial fishers to handle and deliver their harvest efficiently and economically.