Fang zhouzi
In recent years, "spicy crayfish" has become a famous dish popular all over the country, and even a street of crayfish has appeared in some cities. Sitting in the food stalls lined up along the street and eating "hemp" while drinking beer is a kind of enjoyment in hot summer. With the popularity of crayfish, there are also some rumors about it. Other famous dishes did not enjoy this treatment. I don't know if it is caused by the horrible appearance of crayfish.
A statement widely circulated on the Internet is said to come from Japanese declassified files, saying that China did not produce crayfish in the past. During World War II, the biochemical troops of the Japanese invaders introduced crayfish from Japan to clean the water source because they had to deal with a large number of corpses, and "survived in Chinese mainland by eating some cremated corpses in China", which sounded disgusting and indignant.
Crayfish (Chinese name Procambarus clarkii) is a kind of freshwater crayfish, and it is really not native to China. Native to North America, 19 18 was introduced from the United States to Japan as bait for bullfrogs, and 1929 was transplanted from Japan to Nanjing, China. At this time, Japan had not launched a war of aggression against China. Of course, crayfish are not used to treat corpses, but are introduced as food and bait.
Crayfish has strong vitality, feeds on decaying plants and small animals in the water, and has a wide range of feeding habits. It can survive in various aquatic environments, even in dirty and polluted environments. So there are rumors on the Internet that the dirtier the environment, the more serious the pollution, and the better the crayfish will live. So crayfish are rich in pesticides, heavy metals and other environmental pollutants. Foreign countries don't eat crayfish to treat urban sewage, only China people eat and eat stupidly.
Crayfish has a strong tolerance to environmental pollution, but it cannot be considered that it likes pollutants and is good at enriching environmental toxins. On the contrary, it is probably because it is not easy to enrich environmental toxins and has a set of "detoxification" mechanism to survive in polluted environment. Domestic researchers found that although crayfish contain many kinds of heavy metals, their contents are lower than the national standards, and most of the heavy metals are concentrated in the shells, gills and internal organs of crayfish, but the content in meat is very low. If you only eat the meat of crayfish and don't eat its internal organs (including shrimp yellow, which many people like to eat), you can greatly reduce the intake of heavy metals.
China is not the only country that dares to eat crayfish. All countries in Africa, Europe and America eat it. Among them, Louisiana is the most important crayfish production and consumption place in the world, and it is an industry with an annual output value of hundreds of millions of dollars. According to the statistics of 1987, 90% of crayfish in the world are produced in Louisiana, and 70% of them are consumed locally. At that time, crayfish was not popular in China, and the world pattern of crayfish has changed greatly in recent years. A considerable amount of crayfish made in China are also exported, so that the United States will impose anti-dumping duties.
These online rumors seem to have no effect on the popularity of crayfish. Since July, it has been reported from Nanjing that some people eat crayfish and their muscles dissolve (medically called "rhabdomyolysis"), which makes many people afraid to eat "hemp" again. Initial reports suspected that traders used "shrimp washing powder" to clean crayfish, and "shrimp washing powder" contained toxic ingredients. It has been reported that the main component of "crayfish" is oxalic acid, which is a strong acid, and its acidity is 1000 times that of acetic acid, which will seriously affect health.
The chemical property of oxalic acid is unstable, which is 189. Decomposition takes place at 5 degrees Celsius, which can't stand the high temperature of Ma Xiao. Many foods naturally contain a small amount of oxalic acid, and a small amount of oxalic acid will not cause obvious harm to the body. If there is still a high content of oxalic acid in the shell of crayfish, the skin and mucosa of hands and mouth will be corroded and it is difficult to enter.
If it is not the "shrimp powder" but the crayfish itself, you may think, has there been a similar situation in other countries and regions that consume crayfish in large quantities, especially Louisiana? Yes, in April 20001year, nine people in Louisiana suffered from rhabdomyolysis shortly after eating crayfish in the same place. There are many factors that cause rhabdomyolysis, such as strenuous exercise, alcoholism, drug abuse, taking certain drugs, bee bites and snake bites, and suffering from certain infectious diseases. But these factors have been ruled out. Possible factors such as heavy metals and pesticides are also excluded.
In the end, these nine people were considered to have a rare disease-Huff's disease. Huff means "shallow lagoon" in German, which refers to the local seawater waters surrounded by sandbars or coral reefs in the coastal zone. The disease was first discovered in 1924 near KoNegus Berg shallow lagoon on the Baltic Sea coast, and there were about 1000 cases in 1000 years. Later, there were sporadic reports in other countries. Since 1984 was first discovered in the United States, only 23 cases have been found so far.
Huff's disease is characterized by rhabdomyolysis within 24 hours after eating cooked aquatic products (fish, crustaceans, etc.). ), but no other factors lead to rhabdomyolysis. It is not clear what kind of toxin is caused, whether the toxin is synthesized by the organism itself or ingested from the environment. Some people speculate that it may be a toxin similar to hydra toxin, but hydra toxin only exists in marine organisms, but not in freshwater organisms, and most patients with Huff's disease get sick after eating freshwater aquatic products.
Because the toxin of Huff's disease has not been identified, it is impossible to detect the food, and it is impossible to know which foods may be pathogenic and which are safe. If the crayfish incident in Nanjing is also caused by Huff's disease (Editor's Note: On September 7, the Nanjing Municipal Government informed that the symptoms of this crayfish incident are basically the same as Huff's disease), its uncertainty may make people feel even more horrible. However, Huff's disease is an extremely rare disease, which occurs occasionally and is often one-off. So many people in Louisiana have eaten crayfish for so long, and only one epidemic has caused nine people to be poisoned. These people later recovered, and there was no panic in the local area at that time. We don't need to panic now If you are afraid to eat crayfish because of this, other aquatic products will also cause Huff's disease. Don't you eat any aquatic products?
Source: China Youth Daily
Author: Fang