Aquatic products generally need to be processed, stored, transported and sold before they reach consumers. In these processes, the time is relatively long. In order to prevent the corruption and deterioration of aquatic products, it is necessary to master the core technology in the storage and processing of aquatic products and use effective measures. Only by keeping aquatic products fresh can we reduce the economic losses caused by the transportation and sale of aquatic products.
Most of aquatic products are fish products. Because the tissue of fish is very fresh and tender, it is not easy to keep fresh compared with other products of livestock and poultry. Therefore, only in the process of processing aquatic products, the process and methods are constantly improved to keep the aquatic products fresh.
Overview of Processing and Storage of Aquatic Products
As a discipline, aquatic product storage and processing has made many studies on the storage, processing and preservation of aquatic products. In recent years, in order to adapt to the development of society and market trends, aquatic products processing industry gradually began to go deep processing, marine active substances development and utilization direction research, deep processing technology will become the development direction of aquatic products industry. This requires continuous upgrading of the technological content of aquatic products processing, in-depth study of aquatic products processing and preservation technology, accelerating the industrialization process of new technologies and achievements in processing and preservation of aquatic products, so as to continuously optimize and upgrade the industrial structure of aquatic products. At the same time, modern analytical technology should also be developed for aquatic products. In order to improve the quality and safety of aquatic products, the inspection of harmful substances in aquatic products should be carried out, and the supervision of aquatic product quality should be strengthened.
The development of aquatic products in storage and preservation technology has gone through half a century. It has developed from the initial use of ice and salt to the direction of ice-temperature, micro-freezing, rapid freezing and cold seawater preservation. With the development and innovation of various technologies, now equipped with heat preservation, plate freezing and other equipment on fishing boats to keep aquatic products fresh. Mainly through the low-temperature refrigeration chain, the fresh-keeping of aquatic products on land can basically ensure that the process of fishing, processing and circulation of aquatic products is carried out in low-temperature environment, and the quality of aquatic products can be better maintained.
Common methods of processing and storage of aquatic products
Mastering the skills of processing and storage and effectively reducing the spoilage of aquatic products through fresh-keeping measures is a difficult point in the process of fresh-keeping of aquatic products. Here are some brief descriptions of the techniques of fresh-keeping and storage of aquatic products.
(1) Low temperature treatment throughout the process
There are two main causes of spoilage and deterioration of aquatic products. One is the growth and reproduction of microorganisms, and the other is the activity of inherent enzymes in food. Corrupt microorganisms are generally in the stage of more vigorous reproduction in the temperature range of 25 to 45℃. Only when the temperature drops below 10℃, their reproduction will be limited by temperature. When the temperature drops to about 0℃, the reproduction of corrupt microorganisms becomes very difficult. When the temperature drops to about 0℃, the reproduction of corrupt microorganisms becomes very difficult. At minus 10℃s, these microbes can hardly reproduce.
At the same time, lower temperature can inhibit the autolysis of tissue enzymes. At 0℃, the autolysis of tissue enzymes almost stops. Therefore, in the process of processing and storage of aquatic products, low temperature is very important for the preservation of aquatic products. Low temperature treatment is generally divided into two types, cooling and freezing. Cooling is to cool aquatic products to about 0℃, while freezing is to freeze aquatic products in the environment of minus 18℃, so the former is mostly used for short-term or temporary storage, while the latter is used for long-term storage of aquatic products.
(2) Reducing the moisture content of aquatic products
Water content in aquatic products has a direct impact on bacteria and enzymes. Generally, the development of bacteria requires 50 to 60 percent of water conditions. Reduction of water content can not only effectively inhibit the growth and reproduction of bacteria, but also have a greater inhibition on the activity of enzymes. Therefore, water in aquatic products can be reduced by reducing water content. The content of components can effectively delay the corruption of aquatic products. Usually there are three specific methods: dry curing, wet curing and mixed curing.
(3) Smoke and fire roasting
The smoking and roasting process of aquatic products can form a unique smoking flavor, but also make the aquatic products not easy to rot. This is because in the process of smoking, phenols, alcohols, acids, hydrocarbons and other substances contained in water vapor, gas, resin liquid and particulate gas in the air can eliminate bacteria. Generally, the combination of smoking and cooking can form a stable color and unique odor through the action of heat. But the disadvantage of this method is that it can not avoid the growth of mould.
(4) Dry processing of aquatic products
Drying process is to prevent bacterial reproduction by removing water from aquatic products. There are two main ways: natural drying and artificial drying. Natural drying mainly includes sun drying and air drying. Artificial drying is divided into baking, baking and freezing. The natural advantage is that the method is simple, easy to operate, low cost, and can be processed in large quantities. The disadvantage is that the quality of aquatic products after drying is low and mildew easily occurs. Artificial drying requires higher technology, cost and equipment, but the quality of dried aquatic products is better and the preservation effect is better.
(5) Cooking aquatic products by heating
Heating and cooking of aquatic products can affect the denaturation and coagulation of proteins, destroy the activity of inherent enzymes and kill microorganisms. But after the aquatic products are heated and cooked, they should be insulated from the air. Therefore, they should be sealed and packed or filled with inert gases in sealed containers to remove oxygen and prolong the storage time of aquatic products. This method is mainly used for the storage of dry aquatic products.
(6) Storage of aquatic products by physical and chemical methods
The physical treatment of aquatic products can greatly reduce the loss of aquatic products and prolong the shelf life of aquatic products. Ultraviolet radiation and atomic energy radiation are common methods, but these methods are expensive and limited. Atomic energy radiation can easily produce radioactive substances in aquatic products, which must be used strictly in accordance with the regulations. Chemical method is to preserve aquatic products by using some anticorrosive effects of chemical substances. However, there are few chemicals that can be approved for food preservatives in the process of preservation of aquatic products, and they also have great limitations.
Aquatic products packaging
Common packaging methods for aquatic products / seafood products for storage and retailing, include vacuum packaging, MAP modified atmosphere packaging, VSP vacuum skin packaging. MAP and VSP packaging are mostly used in retailing for better product appearance that keeps aquatic products’ original color and flavor.
Visit KANGBEITE PACKAGING official website for related packaging machines.