Where does the toxin in pufferfish come from?
Anchovy, swordfish and pufferfish are collectively known as the "Three Delicacies of the Yangtze River" and have been delicacies that gourmets have been flocking to since ancient times.
Song Dynasty scholar Su Shi’s poem "Evening Scene on the Spring River in Huichong" provides evidence: "Three or two branches of peach blossoms outside the bamboo are a foreteller of the warmth of the spring river. The ground is covered with wormwood and short reed buds, which is when puffer fish are about to come."
Puffer fish enjoys the exclusive reputation of "King of Fishes". Its nutritional value is well known. It is extremely rich in protein, unsaturated fatty acids, DHA, EPA and other nutrients, and its fat content is extremely high. But it's very low.
However, although pufferfish tastes delicious, it is poisonous. Every year, there are several news reports about diners taking the risk of eating pufferfish for a taste, resulting in poisoning, ranging from hospitalization to death, which also makes many People talk about pufferfish, but what kind of fish is pufferfish? Why is it poisonous if you eat it? How can you taste puffer fish safely without getting poisoned? Let me tell you something about puffer fish.
Although most people have heard the name of pufferfish, you may not know whether the correct spelling is pufferfish or puffer fish.
Some people think that the correct way of writing it should be Hefu, with the word "tun" next to the word "fish" on the left and the word "tun" on the right. However, puffer fish is the real name!
Because puffer fish have a special skill, when they are frightened or angry, they will quickly swallow a large amount of water or air, turning themselves into a round shape, and they look very similar when floating on the water. A fat little pig floating on the water was called "puffer fish" by the ancients. The word "Fugu" was created by later generations and was mainly used in taxonomy to name this type of fish.
Broadly speaking, in taxonomy, the fishes of the order Pufferfish include the largest bony fish - sunfish, the bad-tempered scale puffer, the horse-faced puffer commonly known as the mouse fish, and the spiny puffer. , it can be said that it is a kind of puffer fish.
But in a narrow sense, only puffers living in fresh water, especially several "oriental puffers" that are often used as food fish, can be called "puffer fish". The most common one on the table is "dark puffer fish". "Patterned Oriental pufferfish", it is probably the pufferfish in Su Xueshi's poems.
Why is puffer fish poisonous?
The toxin in puffer fish is called "tetrodotoxin", which is an extremely powerful neurotoxin. It only takes about 2 milligrams to cause death. The content of tetrodotoxin in an adult female puffer fish is, It can kill you about 30 times or more. After poisoning, symptoms such as numbness of the mouth, tongue, and fingertips, dizziness, vomiting, and diarrhea may occur. In severe cases, numbness of the limbs, unconsciousness, drop in blood pressure, coma, and even death may occur.
And there is no detoxification drug invented yet. It is said that the ancients would inject feces juice to induce vomiting after discovering poisoning. In modern times, gastric lavage is mainly used to remove the toxins left in the body. Tetrodotoxin is not only powerful, but also extremely stable and cannot be destroyed by ordinary cooking methods. This makes many diners turn away from fugu.
But the good news is that tetrodotoxin is not found in pufferfish itself, and it is not poisonous throughout the body.
The current mainstream research view is that pufferfish produces tetrodotoxin through some bacteria in the body, and these bacteria are enriched and gradually accumulated in the body through food, and the toxin mainly exists in the ovaries, Pufferfish muscles are virtually non-toxic to organs such as the liver, blood, eyes and skin.
In Japan, only specialized restaurants can sell puffer fish dishes, and chefs who handle puffer fish must undergo years of professional training before they can prepare puffer fish dishes for customers. Moreover, there are very complicated and delicate steps when handling pufferfish:
1. Use running water to clean the pufferfish, remove the mucus on the body surface, and cut off the fins.
2. Use a sharp knife to carefully insert between the fish skin and fish meat to separate them, and peel off the fish skin without damaging the skin or fish meat.
3. Use a towel to absorb the moisture on the surface of the fish, and then take out the fish eyes.
4. Carefully remove all internal organs without breaking them, otherwise toxins may contaminate the fish.
5. Open the fish skull and take out the fish brain.
6. Wash the fish repeatedly with running water to remove all blood and body fluids.
7. Check at least twice before cooking to confirm that all poisonous organs have been removed and properly destroyed.
Even if you are so careful, you will occasionally hear about people being poisoned by eating pufferfish, especially in spring, when such news is the most common. Why is this?
Two reasons: one is that spring is the traditional season for eating puffer fish, and the other is that puffer fish is the most toxic in spring.
Take the Oriental pufferfish as an example. They usually migrate to freshwater to lay eggs in spring. They need to accumulate a lot of fat in their bodies during the breeding season. The fish meat at this time is the most plump. Not only does it produce a large amount of food, but it is also edible. There will also be more people eating pufferfish, and there will be more reports of poisoning.
Furthermore, the ovaries of pufferfish are the most toxic organs. In order to lay eggs, the ovaries of female pufferfish will mature and increase in size and mass, which increases the chance of poisoning.
So is it possible for us to taste puffer fish safely? The answer is yes.
At present, scientists engaged in fishery technology in our country, after years of hard work, have artificially cultivated four kinds of puffer fish: obscurous pufferfish, red-fin pufferfish, double-spotted pufferfish and chrysanthemum yellow pufferfish. A drug-free strain was developed.
By completely isolating the pufferfish from the outside world in an artificial environment and feeding it with artificial feed, the pufferfish cannot obtain toxin-producing bacteria, and multi-generation breeding is carried out to select pufferfish individuals with less toxins in the body. , allowing their offspring to gradually reduce the toxins in their bodies, and finally obtained stable non-toxic puffer fish.
In 2016, my country's former Ministry of Agriculture issued the "Notice on the Registration of Breeding Puffer Fish Source Bases", and the former Ministry of Agriculture and the State Food and Drug Administration jointly issued a document "On Conditionally Opening Up the Breeding of Red Fins" "Notice on the Processing and Operation of Oriental pufferfish and cultured pufferfish". Since then, my country's puffer fish has been officially included in the conditional opening.
The document sets out very strict management requirements for the opening of puffer fish, including: the source base of puffer fish farming must be registered, the processing of puffer fish farming must be assessed, puffer fish must have safe processing procedures and puffer fish product quality There are standards.
To draw an important point, if you want to taste puffer fish safely, you must choose artificially cultured fish that meet the above requirements, and find a restaurant that specializes in puffer fish to ensure that you will not be poisoned while tasting delicious food. danger.