CATDOLL : CATDOLL: Pufferfish; how to distinguish between farmed and wild ones?

1. Pufferfish: How to distinguish between farmed and wild ones?

Farmed puffer fish are all raised with feed, which is less toxic and costs about 100 yuan per kilogram. Wild puffer fish are highly toxic and can also cause poisoning during processing. Wild puffer fish are very rare, so the price is also sky-high, generally around 2,000 yuan per kilogram, and it can cost five figures when it is expensive. So it is easy to distinguish, and the price difference is very large, just like the difference between farmed ginseng and wild ginseng. Wild puffer fish must be processed by professionally trained people, which is very troublesome. The blood, internal organs, brains, eyes, and gills must be thrown away. When picking the fish, no blood can be seen, and the knife skills must be very good. I have studied Japanese cuisine and can only make sashimi, hot pot, and deep-fried. It is delicious when eaten raw, and dipped in ポンス sauce.

2. How to distinguish wild and farmed puffer fish?

Wild ones have a strong fishy smell, while farmed ones have no smell

3. Can wild pufferfish be farmed?

According to Director Zhou Guoping, both wild and farmed pufferfish are poisonous; but since farmed pufferfish are edible, why does the government still not lift the ban?

What is a wild pufferfish?

There is no antidote for pufferfish poisoning, and the so-called treatment is only symptomatic. Generally, mild poisoning can heal itself after a few weeks, but now farmed pufferfish are almost non-toxic, while wild ones are still very toxic, which depends on the cooking skills of the chef.

5. How can we remove the toxins from puffer fish?

The issue of pufferfish commercialization has been a hot topic recently, with the focus being on pufferfish toxins. According to experts, pufferfish are poisonous, but the toxins can be removed through careful handling.

The location of tetrodotoxin and seasonal changes The location of tetrodotoxin is the internal organs of the fish. This includes: gonads, liver, stomach and intestines. The amount of toxicity varies due to different breeding environments and seasonal changes. According to the examples of Yangtze River pufferfish and artificially cultivated pufferfish, the toxicity of each organ is as follows: ovary > spleen > liver > blood tendons > eyes > gill rakers > skin > testes > muscles. The toxicity of the organs of cultivated pufferfish (over 2 years old) is consistent with that of wild pufferfish, but the amount of toxin is lower.

The reproductive glands are the ovaries and testes. The ovaries are highly toxic and are one of the most toxic parts of pufferfish. The testes are slightly toxic or non-toxic. The ovaries and testes are oblong and located in the back of the abdominal cavity, near the anus. The two are easy to distinguish during the reproductive period. The testes are milky white and the ovaries are light yellow. In cross-section, the testes are white and milky, while the ovaries are granular. However, in autumn, because the reproductive period has passed, the ovaries and testes are atrophied and it is difficult to distinguish between the two.

The liver is a large, long organ located on the right side of the abdominal cavity, connected to the enlarged stomach above, with the lower tip reaching near the anus. It is gray-brown in color, with a green gallbladder inside. The liver is the highly poisonous part of pufferfish, so special attention should be paid to removing it cleanly before eating. Artificially farmed pufferfish can be eaten after frying.

Skin and blood: The amount of toxin in the skin varies with the type of pufferfish. The skin of pufferfish contains little or no toxin. The blood, especially the two so-called spinal blood clots, or spleens, contain highly toxic substances.

Stomach and Intestines The stomach is very large and can absorb water or air to make it expand. Below the stomach is the intestine, which makes two folds in the abdominal cavity to reach the anus. The stomach and intestines are also poisonous, but their toxicity is much less than that of the ovaries and liver.

Muscles Muscles can be considered non-toxic, so as long as the pufferfish's internal organs are removed, the skin is peeled, and it is washed clean, it will not be toxic. However, the pufferfish has been dead for a long time, and the toxins in the internal organs are dissolved in the body fluids. Over time, they can penetrate into the muscles, so we must be careful. Especially when making fish fillets (fish sashimi), it is safer to soak them in 2%-5% alkali solution.

The ovaries and liver of pufferfish are the second most toxic organs in the pufferfish. The amount of poison they contain often varies with the seasons. From February to May each year, the ovaries are in the development period, and the toxicity is relatively strong. After June and July, the spawning period has passed, the ovaries shrink, and the toxicity is also weakened. The liver is the same as the ovaries, and the toxicity is generally stronger in spring. In addition, the toxicity of different species is also inconsistent, and even the same species, the toxicity is sometimes inconsistent. Generally, females are more toxic than males.

We have conducted a toxicity study on the dark-striped pufferfish, taking the ovaries, muscles, testes, and livers of 3-year-old (2-winter-age) sexually mature dark-striped pufferfish and conducting toxicity tests on mice. If we use the toxicity of 1000 mouse units (MU), which is equivalent to 1g of poisonous pufferfish organs being lethal to 1kg of mice, the toxicity of the ovaries, muscles, and testes is less than 6.6 MU, 4.5 MU, and 8.1 MU, respectively.

Regarding the issue of pufferfish detoxification and safe consumption, experiments have proven the reliability of high-temperature heating to destroy toxins, that is, the detoxification of wild pufferfish heated at 120°C for more than 2 hours, and the detoxification of farmed pufferfish at 120°C for 30-40 minutes can achieve the purpose of complete destruction of toxins and safe consumption. Pufferfish meat can be used as rape cooked food or canned food. This temperature and time condition can be strictly controlled in mass production to ensure food safety. At the same time, the processing method of heating to destroy toxins can maintain the unique deliciousness of fresh pufferfish meat. After processing in the flood season in the fishing area, it can adjust the market supply and demand needs, and it can be supplied all year round in the breeding area.

Toxicological test: Each batch of products should be tested on animals, such as rats, cats and dogs. It is advisable to eat only after no abnormal reaction. According to the chemical test results, Nessler's reagent is the most sensitive. After diluting it to 100 times, it can still show an obvious positive reaction. The color of the reaction is also special, which is different from the positive reaction caused by ammonia. This qualitative reaction can also be used for testing to determine whether it contains tetrodotoxin.

Farmed pufferfish has low toxicity. As long as the operation is strictly in accordance with the regulations, it has broad development prospects and is conducive to the protection of natural resources and the development of local specialty varieties. What needs to be done now is to carry out extensive publicity and education to the people in the production areas, issue and implement the trial measures for the management of pufferfish, and implement the processing and operation procedures for the safe consumption of pufferfish. Through processing, it is necessary to prevent the arbitrarily discarded internal organs from causing accidental ingestion by humans and animals (areas without conditions also need to properly handle them, such as deep burial or acid hydrolysis of internal organs), so as to ensure safety, turn harm into benefit, increase income, and promote the development of pufferfish farming and production.