Mineral water product is an important by-plant in the market, and it is an important source of protein and other nutrients. Now people can eat seafood in the form of processed products and fresh products. In recent years, people's living standards have been improving, and people's requirements for seafood and seafood quality are also higher and higher. In particular, the demand for fresh seafood and marine products is also increasing. At the same time, with the growing development of aquaculture, the production of seawater and freshwater aquaculture has developed into factory, intensive and professional. Marine fish are also mechanized. There are many kinds of seafood, The quantity is increasing and the grade is getting higher and higher. However, fresh seafood needs to be transported inland and supplied to seawater bars in various cities. This road is very long, so the requirement of the times is to let people eat fresh seafood and do a good job in biological transportation. Over the past three years, aquatic products have been stored, transported and sold in cold zone and freezing mode. Improper processing has resulted in great loss and waste. In recent years, the economic benefits of fresh seafood have been greatly improved, which is a kind of fresh seafood. This one tastes good and sells well, cold John, Because the price is much more expensive than frozen food, although the cost of organism transportation is higher, it can save the cost of freezing, and can get high quality and high price, so the management of seafood products can get more benefits. With the development of social economy, people have to pay more attention The demand for this live fish and shrimp is increasing rapidly. They don't want to eat frozen seafood instead of spending a lot of money on live fish and shrimp. More and more hotels and restaurants provide customers with fresh seafood, especially high-grade lobster, abalone, minnow and so on. It can be seen that biological transportation is one of the important parts of aquatic products sales, and the most important thing is the death of seafood products in the process of transportation Because the environment is not good, so to avoid the fish's physical weakness.
one The main reason that affects the development of seafood market is that many operators lack scientific knowledge about seafood protection before they plan to transport to hotels. The key factor of biological transportation is that before biological transportation, the object of transportation is in the process of transportation First of all, we should realize that the environment we live in is different from the original living environment. Due to the obvious differences in the environment, the physiological conditions of the human body will change. Serious people will threaten the survival of organisms and directly affect the activity rate of transportation. Second, live aquatic products In the process of transportation, the main factors affecting the changes of biological physiological conditions were analyzed, such as oxygen, temperature, carbon dioxide, ammonia nitrogen, etc. If the oxygen is insufficient, the seafood can not breathe normally during transportation. Severe hypoxia will cause asphyxia and death, and affect the activity rate. Generally, the oxygen dissolved in water should be maintained at more than 5mg / L during transportation. Therefore, oxygen should be provided during transportation, There are several ways to supply oxygen: A. the oxygen content in the water can be increased by injecting new water during transportation. The temperature and salinity of the new water are almost the same as that of the old water. B. proper vibration of the transporter can increase the contact surface between water and air, and make the mountain more stable To dissolve the cow, pay attention not to let the carrier shake too much, C. set a mesh plate in the water surface of the carrier, rotate at a slow speed to increase the vibration of the water, D. set an oxygen charger during transportation to increase oxygen at any time.
two Temperature fish and other animals are variable temperature animals, and their body temperature varies according to different water temperatures. All kinds of aquatic products have suitable temperature range, and it is easy to die if they exceed the suitable temperature range. In the process of transportation, the water temperature must be adjusted well. High temperature, biological metabolic rate and oxygen consumption, and the temperature of the water is high, Moreover, the resulting carbon dioxide and ammonia content is also very high, but also dissolved oxygen, weakening the affinity of blood and oxygen in the organism, so when changing water, adding water or adding ice, it is necessary to prevent rapid changes in temperature. With the sudden change, whether the internal machines of fish can adapt to this change, fish are easy to get sick. In summer, the temperature is too high, and there is a little ice on the water surface, which can slowly melt and reduce the water temperature. In winter, the water temperature is too low, so we should take some measures. To be drunk, the change of water temperature should not exceed 5 ℃. Carbon dioxide fish in the water breathing will emit carbon dioxide, increase the concentration of carbon monoxide in the water. The harmful concentration of carbon dioxide to fish is 60-100mg / L. At this time, even if the dissolved oxygen in the water is saturated, the fish will not be able to breathe normally and may suffocate. Generally, the concentration of carbon dioxide in the tank during transportation is 20 × 10-6-30 × 10-6. If the concentration of carbon dioxide exceeds this range, the water will be pumped. To discharge high carbon dioxide, dissolved oxygen in water, maintain the normal living environment of fish.
four Due to the effect of feces, residual bait, dirt and bacteria discharged by fish and shrimp, the ammonia nitrogen content in water increases continuously. The accumulation of ammonia nitrogen in water at a certain concentration will weaken the oxygen absorption capacity of fish and shrimp and make the organism normal Obstruct the breathing of the enemy. Because ammonia is very harmful to the body of fish, generally, if the concentration exceeds 0.012 × 10-6, the fish will be in fatal danger. Generally, when the water temperature rises, the ammonia emission of fish will increase, and that of small fish will increase. It's more than big fish, so it's necessary to replenish a lot of oxygen during transportation to avoid fish poisoning and death or damage. The osmotic pressure of organisms, such as fish and shrimp, can secrete mucus or scales to maintain the balance of osmotic pressure in the body Shrimp and other systems are mechanically injured by water tanks or cages, scales and mucus fall off, epidermis falls off, osmotic pressure in the body loses balance, and the resistance of fish to diseases decreases, so as to reduce the surface damage of fish or reduce the surface damage of blood. Therefore, normal osmotic pressure should be maintained.
six Before transportation, fish, shrimp and other organisms have strong physique, strong adaptability to harsh environment, and high activity rate of transportation. When seafood is caught by transportation equipment, they can not adapt to the new environment or their muscles are stiff due to surprise. At this time, if there is not enough oxygenated blood, a large amount of lactic acid will accumulate in the muscle vessels, the pH value of blood will decrease, and the utilization rate of oxygen by acidic blood is low, It is difficult for shrimp to return to normal within 24 hours. The slow recovery depends on the species and constitution of organisms. Therefore, healthy individuals must be selected before transportation to ensure the survival rate.
seven In the process of transportation, the seafood that can prevent bacteria from propagating will secrete a lot of mucus and excreta in an inconvenient environment. This secretion will become the culture agent of bacteria and multiply bacteria. On the other hand, the bacteria will infect the seafood. On the other hand, the growth of bacteria will consume oxygen and reduce the content of dissolved oxygen in water. Seafood is easy to die due to lack of oxygen. In addition, in the process of transportation, if there are food residues in the digestive organs of fish, bacteria will also enter the intestines and stomach and die in large numbers. The active rate of seafood was high after breeding.
