Introduction of tuna

Tuna, also known as tuna or tuna, is a migratory fish that can freely shuttle in the Pacific Ocean, Atlantic Ocean and Indian Ocean. Because it can be fished everywhere, it is also called "fish without national boundaries".

The swimming speed of tuna, an excellent swimmer, is among the best among fish. Its speed is usually 60-80 km/h, up to 160 km. Because the gill muscles of tuna have degenerated, they can only breathe through their gills with their mouths open, which makes them have to swim all the time and suffocate once they stop.

Warm-blooded youth-most fish are cold-blooded animals, but the temperature of tuna is 9 degrees higher than the surrounding water temperature on average, which is mainly because the muscles on both sides of tuna spine are well developed and there are a large number of vascular networks on the skin. These parts have a very strong metabolism, which provides a lot of energy for the tireless swimming tuna.

Common tuna

There are eight kinds of tuna, among which bluefin tuna is the most famous, which can be called Rolls Royce of tuna. This species is divided into Pacific bluefin tuna, Atlantic bluefin tuna and southern bluefin tuna, which are now on the verge of extinction due to overfishing.

Big-eyed tuna-close to the blue fin, up to 2 meters long, weighing 150 grams, with large eyes and pectoral fins.

Yellow fin tuna-named after yellow dorsal fin and anal fin, is richer in resources than blue fin and is an important economic fish.

Albacore tuna-long ventral fin, small size, body length 1 m, pink meat, also known as platinum gun.

Blackfin tuna-small in size, with a body length below 1 m, abundant, reddish in meat and bitter in taste.

Bonito: The meat is very hard, and it is often used as canned tuna in Japanese cuisine to make muyu flowers.

The history of tuna business

Before the 1930 s, tuna was regarded as prey by many sea fishing sailors because of its large size and fast swimming. At this time, tuna is perishable because of the lack of perfect cold chain facilities, and is regarded as cheap cat food.

1970s, Japan's economy entered a period of rapid development. At the same time, it exports refrigerator color TV sets to the United States, and imports seafood ingredients such as caviar and deep-sea fish from the United States. Eating habits began to be Europeanized, and tuna gradually became popular in Japan.

2 1 century, with the popularity of Japanese sushi in the world, coupled with various marketing implants such as variety shows, advertisements, TV dramas, magazines, etc., tuna that evolved into a particularly difficult catch began to become delicious on people's tables.

Nutrition of tuna

Tuna is a typical high-quality meat with high protein, low fat and low calorie. As a deep-sea fish, it is rich in DHA (commonly known as brain gold) and unsaturated fatty acids such as EPA and taurine, which is helpful to the development of brain nerve cells and visual system, and can also reduce blood lipid and cholesterol and prevent cardiovascular diseases.

In addition, tuna is rich in essential amino acids and minerals such as potassium, sodium, calcium, magnesium, phosphorus and iron, among which methionine and cystine help to protect the liver and enhance its detoxification function, potassium helps to maintain cell permeability, calcium is an important component of human bones and teeth, and iron can prevent anemia.

Tuna fish in water versus tuna fish in oil.

There are many canned tuna products, including water immersion and oil immersion, mainly because of their different tastes and calories. Oil-soaked tuna can lock in water to a greater extent, so it has a stronger taste and is suitable for making pizza, but it has a relatively high calorie, while the water-soaked tuna has a relatively light taste and is more suitable for making diet meals or salads.

Little is known about tuna

The price of tuna will be divided according to the grade and position. Generally, the higher the oil content, the higher the price. The belly meat in the front abdomen has high fat content, smooth taste and the highest price. The upper abdomen contains moderate fat and is fresh and tender. The naked fat content in the back is the least, and the protein content is relatively high.

In 20 19, at the tuna auction in Tsukiji seafood market in Japan, a chilled bluefin tuna weighing 278kg was sold for 330m yen (about 20 million RMB), setting a new record for tuna.