Why does the sea smell fishy, and why does the fish smell fishy?

Xinhua News Agency (Xinhua) -- British researchers said a few days ago that they had found genes specific to certain marine microorganisms. It is the unique mechanism of this gene that produces the gas that forms the smell of the sea.

Scientists previously knew that some bacteria could often be found in the places where marine life died. These microorganisms feed on the decomposing residues of marine organisms and decompose them to produce dimethyl sulfide gas. Dimethyl sulfide, also known as methyl sulfide or dimethyl sulfide, is what creates a marine flavor with a unique fishy smell.

The researchers thought that only one enzyme controlled the production of dimethyl sulfide, but the results showed that the mechanism that controls the production process of dimethyl sulfide in these microorganisms actually has a "switch". Only when the decaying debris of sea creatures appears around them does the "switch" that creates the scent of the sea turn on.

Resources. Well, to put it simply, the debris of the sea life in the sea dies and then decomposes, producing some kind of smelly substance, so you smell something fishy, and it has nothing to do with the sea itself, the fish itself, you know? I'm going to make you figured it out, and I think you'll be able to understand it this time

It has something to do with microorganisms in the ocean. Every day, the ocean releases a lot of droplets into the atmosphere, and these droplets contain fishy substances and even microorganisms that produce fishy substances, which are brought to the surface when it rains in cities close to the sea.

There is fish in it on the one hand, maybe it is fishy itself, and the rain also has a fishy smell, which is caused by the environment.

The fishy smell of fish is due to the fact that there is a substance called trimethylamine oxide in the body of fresh fish, which is reduced to trimethylamine by enzymes as the freshness of the fish decreases. The higher the trimethylamine content, the stronger the fishy smell of the fish. Generally, freshwater fish contain less trimethylamine oxide than marine fish, so when its freshness is reduced, the fishy smell will not be as strong as that of saltwater fish.

Fish that live in the sea, such as hairtail, yellow croaker, etc. Marine fish will die in fresh water, the reason is: the sea water density is high, the pressure is strong, the sea fish will die in fresh water is because the blood pressure of the sea fish adapts to the sea pressure, after entering the fresh water, the blood pressure of the sea fish is small, and the blood pressure of the sea fish exceeds the water pressure, resulting in the bursting of blood vessels and death.

The fishy smell itself is the mucus of the fish and the foul-smelling substances that enter the muscles. Everyone knows that fish mucus has a fishy smell, but in addition to this, there are also fishy substances in the muscles, which are dissolved in river water or pool water.

The salt concentration in the body of freshwater fish is higher than that of freshwater, and the water will enter the body, and the water flows from the place where the salt is relatively light to the place where it is thick, and the force of water movement is called the soaking pressure, and it is the effect of the soaking pressure that makes the odorous substances dissolved in the freshwater enter the fish body with the water, and the freshwater fish will naturally have a fishy smell.

Precautions for eating marine fish.

Although marine fish is low in fat, eating too much fish can still lead to high cholesterol.

Fish with contamination should be avoided, as it may cause allergies.

Patients with gout should try not to eat or eat less, because the purine content of marine fish is more, which may lead to aggravation of the condition, and patients with bleeding disorders should try not to eat or eat less, and regular consumption can always have platelet coagulation.

The above content refers to People's Daily Online-7 taboos for eating seafood.

It's that the fish have a fishy smell, but the fishy smell of the sea fish will be heavier. Because it is related to their growth environment, marine fish, that is, fish that grow in the sea, they have been in the sea for a long time, and the sea water has a strong fishy smell and salt smell, and over time, it will be affected.

The smell of sea is a kind of trimethylamine, trimethylamine is the secretion of marine organisms or the substance in feces, it is also a volatile substance, so you can always smell a smell of sea when you come to the beach.

Seawater is a very complex multi-component aqueous solution. All elements in seawater exist in certain physical and chemical forms. The presence of copper in seawater is more complex, and most of it is in the form of organic compounds.

Among the free ions, only a small fraction exists in the form of divalent positive ions, and most of them occur as negative ion complexes. So free copper ions account for only a small fraction of all dissolved copper.

The special smell of the ocean comes from the gases produced by the genes of the bacteria in the sea, which is important because it characterizes the marine climate and also helps some marine animals to find food.

Many bacteria can devour putrefaction in places where marine plants such as plankton and seaweed die, while producing a gaseous substance called dimethyl sulfide. This substance has a pungent airiness, which gives the sea air a salty smell.

Water is fluid, for human beings, the amount of water available is unlimited, seawater is a veritable liquid mineral, with an average of 35.7 million tons of minerals per cubic kilometer of seawater, and 80% of the more than 100 elements known in the world can be found in seawater.

Categories: Education, Science, >> Science & Technology.

Problem description: When you come to the beach, you can always smell a fishy smell, I thought it was the rancid smell of the mudflats by the sea, but when you come to the sea, you can still smell it. Why does it smell this way? What is it that makes God open this smell?

Analysis: Seafood smell is a kind of trimethylamine, trimethylamine is the secretion of marine organisms or the substance in feces, it is also a volatile substance, so you can always smell a smell of sea when you come to the beach.

The fishy smell of fish is mainly determined by two factors: its own substance and the external environment

1. Self-serving substance: the organic matter in the fish body is oxidized to produce odor;

2. External environment: fish absorb fishy components in diet and water. The external environment mainly includes dimethylisoborneol metabolized by microorganisms and geosmin contained in the soil, these two substances have an obvious earthy smell and are volatile, so there will be a fishy smell when such substances accumulate in the body of the old erection fish.

The fishy smell of marine fish is one of the common problems that people have when eating seafood. According to scientific research, the fishy smell of marine fish is mainly caused by a substance, namely dimethyl sulfide.

Dimethyl sulfide is an organic compound containing sulfur and carbon, which are metabolites in many marine organisms. When the muscle tissue of marine fish begins to spoil, these compounds are gradually released through oxidative metabolism, resulting in a fishy smell. In addition, the proteins in the fish meat are also broken down during the spoilage process to produce some amino acids, which are further converted into fishy smells.

Therefore, to reduce the fishy smell of marine fish, you need to pay attention to the following:

1.Freshness: Choose fresh, odorless saltwater fish and rinse thoroughly before cooking.

2.Food handling: Completely remove the non-meat parts such as fish maw and gills, and sprinkle salt, lemon and other antibacterial and deodorant on the surface of the fish.

3.Cooking method: High-temperature cooking methods such as grilling, frying, and roasting can accelerate spoilage, so it is best to choose low-temperature cooking methods such as steaming and boiling soup.

In short, the fishy smell of marine fish is caused by compounds such as dimethyl sulfide, and its impact can be reduced to a certain extent by choosing fresh, processing ingredients and scientific cooking methods, so that delicious seafood can be better presented.