The difference between sea fish and freshwater fish

Fish is delicious and is a favorite food in people's daily diet. There are many types of fish, which can be roughly divided into two categories: freshwater fish and seawater fish. These two types of fish not only taste different, but also contain different nutrients. How to choose to eat different fish according to your nutritional needs?

Regardless of whether it is freshwater fish or sea fish, its nutritional composition is roughly the same, and its overall nutritional value is high.

But generally speaking, the content of EPA and DHA in sea fish is more than that in freshwater fish, and the taste is more delicious.

【sea fish】

There are many fishes living in the sea, including saury, golden pomfret, sea bass, large yellow croaker, small yellow croaker, Spanish mackerel, salmon and turbot.

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【Freshwater fish】

Common freshwater fish include carp, crucian carp, grass carp, silver carp, Wuchang fish, and Luo. Yes, there are about 400 kinds.

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【Difference between sea fish and freshwater fish】

Sea fish and freshwater fish both belong to fish, and the nutrients between the two are generally the same, and their nutritional value is very high. Although there are many similarities between sea fish and freshwater fish, their taste and nutrition are slightly better than freshwater fish.

Nutritionally speaking, sea fish has a higher content of vitamins and minerals because seawater contains a lot of nutrient salts compared to freshwater. In addition, body oil and cod liver oil in sea fish contain a highly unsaturated fatty acid, which contains "brain gold" components, also known as DHA. DHA is an essential nutrient in the human brain. It is of great significance to improve thinking ability and memory [1]. Sea fish is also rich in EPA, and its main function is to slightly lower triglycerides and prevent hypertriglyceridemia and vascular diseases.

Through the analysis and comparison of the EPA and DHA content in the muscle and visceral fat of the above 14 kinds of seawater fish and freshwater fish, it was found that among the samples tested, the DHA content in the muscle and visceral fat of perch among fresh water fish was the highest among all. The tested sample is the first, accounting for 18.6% to 20.1% of its fatty acid composition. In addition, the EPA and DHA contents of seawater fish are generally higher than those of freshwater fish.

But for special populations such as infants, because EPA can competitively inhibit the synthesis of 2 prostanoids from arachidonic acid, thereby affecting their growth and development, freshwater fish with low EPA content is more suitable for infants and young children.

In terms of taste, sea fish tastes fresher than river fish. This is because the swimming range and strength of sea fish are larger than that of river fish, which makes their muscles more elastic and delicious. Ordinary freshwater fish will have a "earthy smell" when eaten. This is because the place where freshwater fish grows is mainly in a water environment with more humus.

【Summarize】

Sea fish and freshwater fish both belong to fish and have high nutritional content. However, due to the difference in the growth environment, there is a certain gap in nutrition and taste. The content of EPA and DHA in sea fish is more than that in freshwater fish, and the taste is more delicious. But in fact, freshwater fish also contains EPA and DHA. It's just that there are not as many sea fish.

Saltwater fish not only consume salt in their food, but also consume a lot of salt from seawater. So its skin, gills and excretory system will take on the function of excretion.

Secondly, seawater fish has fewer intermuscular spines, which is relatively easy to eat. The intermuscular spines are small spines in the muscles, which are used to transmit the force of muscle contraction and help fish coordinate the contraction of muscles. Generally speaking, it is one of the characteristics of lower fishes, while higher fishes rarely have intermuscular spines.

Finally, the content of omega-3 unsaturated fatty acids in marine fish meat is significantly higher than that in freshwater fish.

Fish cannot synthesize omega-3 unsaturated fatty acids by themselves and can only be obtained through food intake. In fact, only a variety of algae in seawater can synthesize omega-3 unsaturated fatty acids.