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Fugu is the Japanese word for pufferfish and is also a Japanese dish prepared from the meat of pufferfish (normally species of genus Takifugu, Lagocephalus, or Sphoeroides) or porcupinefish of the genus Diodon. Because fugu is lethally poisonous if prepared incorrectly, fugu has become one of the most celebrated and notorious dishes in Japanese cuisine. Toxicity
Fugu contains lethal amounts of the poison tetrodotoxin in the organs, especially the liver area and ovaries, and also the skin. The poison, a sodium channel blocker, paralyzes the muscles while the victim stays fully conscious, and eventually dies from asphyxiation. Currently, there is no known antidote, and the standard medical approach is to try to support the respiratory and circulatory system until the poison dissipates.
As of 2008, advances in fugu research and farming have allowed some farmers to mass produce non-toxic fugu. Researchers surmised that fugu's tetrodotoxin came from eating other animals that had the tetrodotoxin-laden bacteria, and developed immunity over time. Many farmers now are producing 'poison-free' fugu by keeping the fugu away from tetrodotoxin-laden bacteria. Usuki, a town in Ōita Prefecture, became famous for selling non-poisonous fugu. No one has been poisoned eating it yet. History
Fugu has been consumed in Japan for centuries. Bones of fugu have been found in several shell mounds called kaizuka in Jōmon period that date back more than 2,300 years. The Tokugawa shogunate (1603–1868) prohibited the consumption of fugu in Edo and its area of influence, yet it became common again as the power of the shogunate weakened. In Western regions of Japan, where the influence of the government was weaker and fugu was easier to get, various cooking methods were developed to safely eat these fish. During the Meiji Era (1867–1912), fugu was again banned in many areas of Japan. Fugu is also the only delicacy officially forbidden to the Emperor of Japan, for his own safety.Eating fugu is sometimes referred to as playing Japanese Roulette, a take on Russian Roulette. Species
The most prestigious edible species is the torafugu or Tiger Blowfish (Takifugu rubripes), which is also the most poisonous. Other species are also eaten, as for example Higanfugu (T. pardalis), Shosaifugu (T. vermicularis), and Namera-fugu (T. porphyreus). The Ministry of Health, Labour and Welfare of Japan has created a list which shows which species contain body parts that can be consumed. Other genera that can be consumed according to them include the pufferfish of the Lagocephalus and Sphoeroides, and the related porcupinefish (Harisenbon) of the genus Diodon. Regulations
Strict fishing regulations are now in place to protect the fugu populations from being depleted. Most fugu are now harvested in the spring during the spawning season, and then farmed in floating cages in the Pacific Ocean. The largest wholesale market for fugu in Japan is in Shimonoseki.
Fugu prices rise in autumn and peak in winter, which is the best time to eat fugu, as they fatten to survive the cold. The fugu is shipped to the restaurant alive and stored in the restaurant in a large tank, usually prominently displayed. Prepared fugu is also often available in grocery stores, which must display official documents that license them to distribute fresh fugu.Whole samples of the species may not be sold to the general public.
Since 1958, only specially licensed chefs can prepare and sell fugu to the public. The fugu apprentice needs a two- or three-year apprenticeship before being allowed to take an official test. The test consists of a written test, a fish-identification test, and a practical test of preparing fugu and then eating it. Only about 35% of the applicants pass the test.This is due to the complex nature of the examination process, with a small miscalculation resulting in failure or in extremely rare cases , death. Due to this rigorous examination process, it is generally safe to eat the sliced fugu sold in restaurants or markets.Furthermore, most fugu sold nowadays comes from fish with only a small amount of toxin. Offal
Selling or serving the liver (the most toxic part) is illegal in Japan, but this "forbidden fruit" is still sometimes eaten by amateur cooks, often with fatal results. After the years following Japan's defeat in World War II, when several homeless people died from eating fugu organs that had been discarded into unsecured trashcans, restaurants in Japan were required to store the poisonous inner organs in specially locked barrels that are later burned as hazardous waste. Cost
A dish of fugu can easily cost ¥5,000 (approx. US$50) but it can be found for as little as ¥2,000 (approx. US$20), and a full course fugu meal (usually eight servings) can cost between ¥10,000 and ¥20,000 (approx. US$100 to US$200) or more. Due to the expense of fugu, the fish is sliced very carefully to obtain the largest possible amount of meat without the poison. A special knife called fugu hiki is traditionally used to slice fugu and it is usually stored carefully in a separate location from other knives. Fugu poisoning
Tetrodotoxin (TTX) is a very potent neurotoxin that shuts down electrical signaling in nerves by binding to the pores of sodium channel proteins in nerve cell membranes. Tetrodotoxin is not affected by cooking.It does not cross the blood–brain barrier, leaving the victim fully conscious while paralyzing the remainder of the body. In animal studies with mice, 8 μg tetrodotoxin per kg body weight killed 50% of the mice. The pufferfish itself is not susceptible to the poison due to a mutation in the protein sequence of the sodium channel pump on the cell membranes.
The symptoms from ingesting a lethal dose of tetrodotoxin may include dizziness, exhaustion, headache, nausea, or difficulty breathing. For 50% to 80% of the victims, death follows within four to 24 hours. The victim remains fully conscious throughout most of the ordeal, but cannot speak or move due to paralysis, and soon also cannot breathe and subsequently asphyxiates. If the victim survives the first 24 hours, he or she usually recovers completely.
There is no known antidote, and treatment consists of emptying the stomach, feeding the victim activated charcoal to bind the toxin, and taking standard life-support measures to keep the victim alive until the poison has worn off. Japanese toxicologists in several medical research centers are now working on developing an antidote to tetrodotoxin.
As mentioned above, commercially available fugu in supermarkets or restaurants is very safe and, while not unheard of, poisoning from these products is very rare. Most deaths from fugu occur when untrained people catch and prepare the fish, accidentally poisoning themselves. In some cases they even eat the highly poisonous liver on purpose as a delicacy. As not all fish are equally poisonous this may not always lead to death, but sometimes give little more than the desired numbness on the lips and tongue while eating and shortly thereafter. But, in many cases this numbness of the lips is only the first step of a lethal fugu poisoning.
Statistics from the Tokyo Bureau of Social Welfare and Public Health indicate 20 to 44 incidents of fugu poisoning per year between 1996 and 2006 in all of Japan, where a single incident may involve multiple diners. Each year, these incidents led to between 34 and 64 victims being hospitalized and zero to six deaths, for an average fatality rate of 6.8%. Of the 23 incidents recorded within Tokyo between 1993 and 2006, only one took place in a restaurant, while the others all involved fishermen eating their catch. Much higher figures have been reported for earlier years, and for example in 1958—the first year the preparation of fugu required a special license in Japan—176 people died of fugu poisoning.According to the Fugu Research Institute 50% of the victims were poisoned by eating the liver, 43% from eating the ovaries and 7% from eating the skin. One of the most famous victims was the Kabuki actor and "living national treasure" Bandō Mitsugorō VIII who requested four servings of fugu liver and, in 1975, died after eating them. The fugu chef of the restaurant could not refuse the request from such a prestigious artist. Subsequently, the chef lost his license for breaking the law.
Scientists at Nagasaki University have reportedly succeeded in creating a non-toxic variety of torafugu by restricting the fish's diet.With over 4,800 fish raised and found to be non-toxic, they are fairly certain that the fish's diet and digestive process are what actually produce the toxins that make it deadly. The non-toxic version is said to taste the same, but is completely safe for consumption. Some skeptics say that the species being offered as non-toxic may be of a different species and that the toxicity has nothing to do with the diet of the pufferfish.
Recent evidence has shown that tetrodotoxin is produced by certain bacteria– such as Pseudoalteromonas tetraodonis, certain species of Pseudomonas and Vibrio, as well as some others– and that these are the source of the toxin in pufferfish.
On August 23, 2007, a doctor in Thailand reported that unscrupulous fish sellers sold meat from the highly poisonous pufferfish disguised as salmon, which resulted in the deaths of fifteen people over the past three years. About 115 people were brought to different hospitals. Fugu was banned in Thailand five years prior.
In March 2008 a fisherman in the Philippines died
and members of his family became ill after they cooked and ate a variety of pufferfish. The previous year four people in the same town died and five others fell ill after eating the same variety of pufferfish. Availability
Most Japanese cities have one or more fugu restaurants. They may be clustered together, as past regulations had placed limits on where the stores may be opened, and the proximity of restaurants made it easier to have fugu delivered fresh. A famous restaurant specializing in fugu is Takefuku, in the Ginza district in Tokyo. Zuboraya is another popular chain in Osaka.
Fugu is also consumed in South Korea, where it is known as bok (복). It is very popular in port cities such as Busan and Incheon. It is prepared in a number of dishes such as soups or salads and also commands a very high price.
Few restaurants in the United States serve fugu; as of 2003, only seventeen restaurants were licensed to do so, of which twelve are in New York.The fugu is first cleaned of the most toxic parts in Japan and then is freeze-flown to the USA under licence, in purpose-built, clear, plastic containers. The fugu chefs for U.S. restaurants are trained under the same rigorous specifications as in Japan.
Sale of fish belonging to this genus is forbidden altogether in the European Union.Scientific usage
Fugu rubripes is a commonly used genetic model organism, particularly useful to bioinformaticians. The Fugu genome is unusually small for an organism of its complexity, and contains very little junk DNA. This compactness makes its genome sequence very useful for identifying conserved functional elements.
Furthermore, the sodium channel blocking properties of tetrodotoxin mean that it is widely used in the study of ion channels in neuropharmacology.