Why is hairtail frozen?
Brief introduction of hairtail
Hairtail is one of the common fish in life. Because of its high yield, it is also called nepotism or hairtail. It is also called fish in Qingdao, Rizhao and other cities. Its body is silver-gray, and its biggest feature is that it is slender and flat, even its internal organs are flat. Hairtail, Pseudosciaena crocea, Pseudosciaena crocea and squid are also called the four seafood in China.
Hairtail is a migratory fish, mainly distributed in warm zone waters of the world. They usually live in waters with a water depth of 60- 100 meters, and migrate to shallow waters when spawning. Hairtail looks weak, but it is actually a very fierce carnivorous fish. When it is resting, its body is vertical, its head is up, and it keeps its balance by swinging its dorsal fin and pectoral fin. When it finds its prey, the hairtail bends, its dorsal fin swings rapidly and pounces on it. Its main foods include krill, bamboo pod fish and so on. And there are cases of cannibalism.
Nutritional value of hairtail
Hairtail has high nutritional value, which contains protein, fat, phosphorus, iron, calcium, vitamin B 1, B2 and other nutrients. Although hairtail is high in fat, it is mostly unsaturated fatty acids, including DHA and EPA. DHA, commonly known as brain gold, helps to strengthen the brain and improve intelligence. EPA is a blood vessel scavenger, which helps to prevent the accumulation of fat in blood vessels, thus preventing cardiovascular diseases such as hypertension.
About the delicacy of hairtail.
Hairtail is not only fresh and tender, but also steamed, stewed, fried, dry fried, stewed, etc., which has created local specialties, such as burrito hairtail in Beijing, dry fried hairtail in Shanghai, chili hairtail in Sichuan, steamed hairtail in Zhoushan and iron pot hairtail in Northeast China.
Why is hairtail frozen?
Why is it difficult to buy live hairtail in the market? This is because hairtail generally lives in the sea area with a water depth of about 60 meters, and hairtail here is used to the high pressure of seawater. When hairtail is caught quickly, the external pressure will be reduced, and the swim bladder in the body will expand rapidly due to the pressure change (the diver's decompression sickness is also similar), so that hairtail will die within 2 hours after coming out of the water.
If you want to avoid this situation, you need to put hairtail in a professional pressure box, which will lead to high transportation costs; Therefore, hairtail is usually frozen after salvage, which can not only reduce the cost but also basically retain the taste and nutrition.
Why is sashimi called sashimi? And hairtail can be made into sashimi?
The statement of sashimi comes from Japan. Because it is not easy to tell what kind of fish the sliced fish is, bamboo sticks will be pricked on it. So sashimi hairtail can also be made into sashimi, but the conditions are very harsh. First, it is generally necessary to wait until hairtail is taken to shallow water before fishing slowly, and then put it into professional equipment for preservation. It is suggested that the time from fishing to serving should not exceed 5 hours.
How to choose fresh hairtail
First, look at the gills. The gills of fresh fish are generally red. As time goes on, the gills will gradually turn black, so don't buy fish with black gills.
The second is to look at the fish eye. The fish eyes of fresh hairtail are generally full and protruding, and the eyes are white, clean and bright, while the fish eyes of fresh hairtail will sink and look fuzzy and turbid.
The third is to look at the fish body and scales. The fish body of fresh hairtail is silvery white, with a relatively complete silver film, and the scales will not fall off easily, while the surface of stale hairtail will not only turn yellow due to oil oxidation, but also scale off when touched.
Yellow-eyed hairtail VS black-eyed hairtail
Hairtail in the market has yellow eyes and black eyes, which is actually mainly related to the origin of hairtail. Black-eyed hairtail mainly comes from northern China, such as Zhoushan, Zhejiang, Dalian, Liaoning and other places, while yellow-eyed hairtail mainly comes from southern China, such as the South China Sea. Most of the hairtail imported from the Philippines is yellow-eyed. In terms of taste, the black-eyed hairtail is smaller than the yellow-eyed hairtail, but the meat is more fishy and lighter, which is suitable for steaming, while the yellow-eyed hairtail has thicker skin and is more suitable for braising or frying.
Will hairtail be reduced?
Among the four major seafood products in China, the catch of Pseudosciaena crocea, Pseudosciaena crocea and cuttlefish is decreasing day by day, but the distribution of hairtail has been very firm, ranking first in the catch of marine fish all the year round, and the annual catch is about one million tons, which is due to the breeding habits and strong adaptability of hairtail. Hairtail spawns twice a year, with a single spawning time of 25,000 to 35,000. Hairtail has fierce personality and few natural enemies during its growth, which is also the reason for its high yield.
However, in recent years, it has been found that the catch of hairtail has a downward trend, from 1 186800 tons in 20 19 to 908500 tons in 20 19; Now scientists are studying whether hairtail can be farmed artificially. Because hairtail has the habit of migrating from deep sea to shallow sea, and cannibalism, it is very difficult to create a suitable habitat for hairtail. Zhoushan Fisheries Research Institute successfully put hairtail into artificial environment for more than two months on 20 17, which laid a good foundation for future exploration.