How does the packaging of the hottest aquatic prod

How to reflect the fresh and living characteristics of aquatic products

the packaging of aquatic products in China has hardly changed for many years. The vast majority of fresh aquatic products are only packed in plastic boxes and transported to the market for retail sale; Frozen fish are packed in PE film and corrugated boxes. They are thawed and retail in the market. Many aquatic products are no longer fresh when sold, greatly reducing their due value. Aquatic products are advantaged products in coastal areas. Paying attention to their packaging can make full use of this regional advantage to create famous brand products in this region and turn advantages into benefits

aquatic products are characterized by freshness and delicious taste, but are prone to corruption. They should be reasonably packaged according to the characteristics of different kinds of aquatic products

bulk fish of aquatic products

fish have more bacteria in vivo and in vitro, but they contain less natural immune elements. Enzymes in fish meat can decompose proteins, resulting in softening of muscle tissue and decline in freshness. When the decomposition products reach a certain degree, the fish will also give off odor, and provide favorable conditions for further breeding and reproduction of bacteria. In addition, fish meat is easily oxidized, resulting in deterioration, discoloration or discoloration of the meat. Freezing and cold storage alone is not ideal for the preservation of fish products. To achieve better preservation effect, the following packaging measures can be used for reference

(1) rigid containers should be used for the packaging of fish. The fish tissue is inherently fragile. After freezing, the internal tissue of the fish will be damaged to a certain extent. If it is excessively squeezed during packaging, it will cause the fish body to be broken and the fish tissue to be further damaged, which will not only affect the appearance, but also deteriorate the meat quality of the damaged part and affect eating. At the same time, when the damaged part is thawed, bacteria are very easy to breed. Obviously, the use of rigid packaging containers that are not easy to damage and collapse is conducive to preventing fish products from various mechanical damage during transportation and handling, so as to maintain the original shape and quality

(2) try to reduce the water loss of fish products. The fish not only loses water during freezing, but also loses water due to the sublimation of fine ice crystals on the surface of the fish during cold storage, which will continuously reduce the weight and freshness of the fish. At the same time, due to the continuous deepening of water evaporation on the surface of the fish, a certain thickness of sponge layer will be formed from the outside to the inside, making the fish lose its original taste and nutrients. Therefore, sealed packaging with packaging materials with water vapor barrier performance can prevent the water loss of fish meat in the process of freezing, refrigeration and sales, so as to maintain its original freshness. It should be noted that there is excess space between the frozen fish products in the package, and the water in the fish body is easy to evaporate, dehydrating the fish meat and causing frost inside the package. Therefore, the gap inside the packaging container should be minimized. If packed in plastic film bags, keep the film close to the fish products

(3) adopt anti-oxidation measures such as vacuum packaging. Fish products contain unsaturated fatty acids, some of which are high in content. When it is oxidized, the fish will turn brown and change its taste. Although the method of adding antioxidant during packaging treatment has certain effect, it will also have certain side effects on meat quality. Vacuum packaging can achieve better fresh-keeping effect. The vacuum packaging of fish needs to extract the air from the packaging container, so the plastic film bag can be close to the fish product, which is very beneficial to reduce the packaging volume and internal gap. In order to prevent oxidation, vacuum packaging must use packaging materials with low oxygen permeability, and the packaging container must be tightly sealed to isolate the oxygen outside the packaging

(4) create "artificial air" to prevent the oxidation of fish products and inhibit the growth and reproduction of bacteria. The so-called artificial air refers to the air that increases the content of carbon dioxide or nitrogen. If fish products are placed in the air with a carbon dioxide concentration of 10%, due to its relatively low oxygen content, it can not only improve the cold storage effect, but also have a good fresh-keeping effect at room temperature. In the cold storage, to realize the artificial air environment, large-scale air conditioning equipment is needed, and its operation cost is high; It is much simpler to realize air conditioning in the packaging container. Just by inflating the packaging machine, a part of the air in the packaging can be extracted, and then filled with a kind of gas. At this time, its debugging system becomes a stepless speed regulating or a variety of protective gases. In this way, the quality of fish products can be effectively protected both in the process of refrigeration and sales

(5) avoid ultraviolet radiation. Ultraviolet rays can promote the oxidation of fish products (such as sunlight, light, etc. contain ultraviolet components) and heat up fish meat. These adverse effects are particularly obvious when fish products are displayed in cold storage. In this regard, opaque materials can be used for the packaging of fish products to prevent the invasion of ultraviolet rays. In addition, printing ink can prevent 90% of ultraviolet rays from passing through. Therefore, printing more pictures and texts with ink on the surface of transparent materials can also play a role in shading

packaging of small batches of fish

for small batches of high-end aquatic products with low yield, it is more valuable to develop their fresh-keeping packaging. At present, the international community pays more attention to the fresh-keeping packaging of aquatic products, and there are many new fresh-keeping packaging methods, which are introduced as follows:

(1) fresh-keeping methods of fish. The United States invented a fish preservation method: put the newly caught fish into plastic bags, inject mixed gas into the bags (including carbon dioxide 60%, oxygen 21%, nitrogen 19%), seal and wrap them, and then put the packaged fresh fish into ordinary warehouses. After 4 weeks, the appearance and taste of the fish have not changed, just like the one just caught

(2) canned live fish. A new kind of canned live fish has emerged in the Japanese market. The method is to immerse the live fish in an anesthetic solution until they are unconscious, and then put them in cans. They will not die within two days. Before cooking, just take out the fish in the can and put it into clean water, and the fish will wake up in about 10 minutes. This kind of canned live fish is easy to carry, clean and delicious

(3) deliver live shrimp packaging. Japan has developed a special packaging container for transporting live shrimp, which uses polyethylene as the inner layer and foam polystyrene as the outer layer, and puts crushed ice between the two layers. The inner layer should be prevented from water leakage, and the outer layer should be prevented from damage. In the polyethylene inner tank where the live shrimp moves, put sterilized seawater and a certain amount of oxygen into it, and then seal it tightly with a cover, and then it can be transported. With this method, the survival rate of live shrimp can be maintained at more than 90% within 24 hours even when the external temperature is as high as 40 ℃

(4) oyster preservation method. Oyster is a world-famous delicious seafood, but it dies quickly after being exposed to water, and it is easy to be contaminated by Listeria and deteriorate. Researchers at the New Zealand Institute of marine fisheries have invented a new process that can turn raw oysters into a kind of oyster that can be stored for a long time and maintain its freshness. This process is to immediately pasteurize the live oysters just caught from the sea after washing the sediment. The temperature is 100 ℃, and the pressure is 1.3KG/m2. In this way, the bacteria attached to the oyster shell can be killed, and then the sterilized oysters are packed with vacuum aluminum foil blister. Because the oyster shell is not opened during pressure sterilization, all the fresh juice in it is retained in the shell. After purchasing the innovative melody made of composite materials, consumers can taste the delicious roasted oysters after heating it in the microwave oven for 2 ~ 3 minutes

in order to improve the safety of food, extend the shelf life and minimize the use of chemical preservatives: