Pufferfish
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 Pufferfish Tetraodon hispidus | ||||||||||||||||||||||||
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The blowfish, swellfish, balloonfish, pufferfish or fugu (Japanese: 河豚 or フグ) is a fish of the family Tetraodontidae (order Tetraodontiformes) named after its ability to inflate itself to several times its normal size by swallowing water or air when threatened. The same adaptation is found in the related porcupinefish, which also have spines. The internal organs of the blowfish are highly toxic. Nevertheless the meat of fugu is considered a delicacy in Japan. In western Japan the fish is also sometimes called fuku.
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2 Consumption 3 Fugu Poisoning 4 Social Aspects 5 Availability 6 Miscellaneous 7 Table of Species of the Genus Takifugu 8 See also 9 External Links |
The Fish
The toxin is called tetrodotoxin, or more precisely anhydrotetrodotoxin 4-epitetrodotoxin and is about 1200 times deadlier than cyanide. This poison can also be found in other animals such as the Blue-ringed octopus, cone snails, or even some newts. The pufferfish does not create the poison itself; rather it is generated by the bacteria Pseudomonas within the fish. The fish obtains the bacteria by eating some food containing these bacteria. Pufferfish that are born and grown in captivity do not produce tetrodotoxin until they receive some of the poison producing bacteria, often by eating tissues from a toxin producing fish. Also, some fish are more poisonous than others. A poisonous fish has enough poison to kill 30 adults.
Tetrodotoxin is a very potent neurotoxin and shuts down electrical signaling in nerves by binding to the pores of sodium channel proteins in nerve cell membranes. 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, 8μg tetrodotoxin per kg body weight killed 50% of the mice. The puffer fish itself has immunity to the poison due to a mutation in the protein sequence of the sodium channel pump on the cell membranes.
Apparently due to some unknown selection pressure, intronic and extragenic sequences have been drastically reduced within this family. As a result they have the smallest known genomes among the vertebrates, while containing a genetic repertoire very similar to other fishes and thus comparable to vertebrates generally. Since these genomes are relatively compact it is relatively fast and inexpensive to compile their complete sequences, as has been done for two species (Fugu rubripes and Tetraodon nigroviridis).
Fugu are also remarkable because they are one of the few fish that can blink and close their eyes (some say the fugu is the only fish that can close their eyes, but there are some sharks that can close their eyes too to protect them while attacking a prey).
Fugu rubripes for sale at the Tsukiji fish market in Tokyo
The most prestigious type for human consumption is torafugu (also known as Fugu rubripes or Tiger Blowfish), which is also the most poisonous. However, other species of the genus Takifugu are also consumed, as for example the fugu pardalis, fugu vermicularis, and the fugu vermicularis prophyreus. The table shows the species which contain body parts that can be consumed according to the Japanese Ministry of Health and Welfare. In addition to that, other genus in the family Tetraodontidae contain pufferfish that can be consumed according to the Japanese Ministry of Health and Welfare, namely some fishes in the genus Lagocephalus, Sphoeroides, and Diodon.
Fugu has been consumed in Japan for a long time, although the historic origin is unclear. The Tokugawa shogunate (1603ÃÂÃÂ1868) prohibited the consumption of fugu, yet it became common again as the power of the shogunate weakened. During the Meiji Era (1867ÃÂÃÂ1912) fugu was again banned in many areas of Japan. Fugu is also the only delicacy officially forbidden to the Emperor of Japan.
A rakugo (comic short story) story tells about three men that prepared a fugu stew, but were not sure about how safe it was. To test the stew, they gave some to a beggar. When they checked on the beggar later, he was still healthy, so they ate the stew. Afterwards they met the beggar again who told them that he was happy that they still looked healthy, so now he knew the stew was safe and he could eat it.
The high demand of fugu has lead to over fishing. Most fugu nowadays is harvested in the spring during the spawning season, and then farmed in floating cages in the ocean. The prices rise in the fall and peak in winter, which is the best time to eat fugu. The fugu is shipped to the restaurant alive and stored in the restaurant in a large tank, usually prominently displayed. As fugu are aggressive and have sharp teeth, their mouths are often sewn shut to avoid the fish injuring each other. Prepared fugu is also often available in grocery stores.
Since 1958, only specially licensed chefs can prepare and sell fugu to the public. The fugu apprentice needs a two (three?) year apprenticeship before being allowed to take an official test. The test consists of a written test, an fish identification test, and a practical test of preparing fugu and eating your own product. Only 30% of the applicants pass the test, which of course does not mean that 70% die from poisoning, rather they made a small mistake in the long and complicated procedure of preparing fugu. Due to this rigorous examination process it is safe to eat sliced fugu sold in restaurants or in the supermarket. Furthermore, most fugu sold nowadays comes from fish with only a small amount of toxin. Selling or serving the most toxic liver is illegal in Japan, but this forbidden fruit is still sometimes eaten by amateur cooks, often with fatal results. Restaurants in Japan are required to store the poisonous inner organs in specially locked barrels that are later burned as hazardous waste, after several homeless people died from eating fugu organs from a trashcan.
A dish of fugu can cost easily 5000 yen (ca. US$50), and a full course fugu meal can cost between 10,000 and 20,000 yen (ca. 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. The most popular dish is fugu sashimi, also called Fugu sashi or tessa, sliced so thin that you can see the pattern of the plate through the meat. While fugu connoisseurs love the taste and the texture of the fugu, most people find the taste actually rather bland and tasteless. Some professional chefs prepare the fish so that there is a minute amount of poison in the meat, giving a prickling feeling and numbness on the tongue and the lips. The fins of the fish are also fried and served in hot sake, a dish called Fugu Hire-zake. Vegetables and fugu can also be simmered as Fugu-chiri, also called techiri, in which case the very light taste of the fish is hard to detect among the taste of the vegetables and the dip. Fugu can also be eaten deep fried as Fugu Kara-age. The more poisonous testicles of the fugu can also be eaten; they contain a milky liquid and taste slightly salty. This is also considered to be an aphrodisiac. If the spikes in the skin are pulled out, the skin can also be eaten as part of a salad called yubiki. The tetrodotoxin is very stable and not affected by the heat of cooking.
Professionally prepared fugu nowadays is very safe to eat. Nevertheless, it seems one of the attractions of the low flavored fish is the play with the risk of potential death, regardless how low the actual likelihood is in a commercial restaurant. This can also be found in the slang name teppo (鉄砲) for fugu, meaning rifle or gun, a play on words on the verb ataru (当たる), which can mean either to be poisoned or to be shot.
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 fishes are equally poisonous, this may not always lead to death, but sometimes give only the desired numbness on the lips and tongue while eating and shortly thereafter. However, in many cases this numbness of the lips is only the first step of a lethal fugu poisoning. If the ingested dose is lethal, the victim may feel dizzy, tired, have a headache, nausea and difficulties breathing as more and more muscles get paralyzed. For 50% to 80% of the victims, death follows within 4 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 asphyxiatess. If the victim survives the first 24 hours, he usually recovers completely.
There is no known antidote, and treatment consists of emptying the stomach, eating activated charcoal to bind the toxin, and giving life support to keep the victim alive until the effect of the poison has worn off.
Some sources claim that about 100 people die each year from fugu poisoning, while others sources say only 10 to 20 per year, and others claim only 1 person per year. This may be due to different years being considered, as 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 got poisoned from eating the liver, 43% from eating the ovaries, and 7% from eating the skin. One of the most famous victims was the famous Kabuki actor and living national treasure Mitsugoro Bando VIII, who died after eating four servings of fugu liver in 1975.
There are some reports of completely paralyzed but fully conscious victims that were believed to be dead, and woke up a few days later or just before being cremated. In some parts of Japan a fugu victim is put next to his coffin for three days to verify the death. If the body does not decompose, it is not yet dead. The tetrodotoxin is also one of the poisons used in voodoo to turn people into zombies.
The popularity of fugu in Japan is an interesting phenomenon. Fugu is a very expensive fish, has some potentially lethal side effects, and is by most people considered to have a very weak taste (although many Japanese gourmets would disagree). The combination of these factors would normally give humans a low preference for its consumption. Nevertheless, it is a very popular dish in Japan. While this may be in part because the consumption of fugu is a tradition in Japan with a long history, it may also be the titillation of playing with death, especially when the actual risk is quite low. It can be assumed that the fish would be much less popular if it would not be so poisonous.
The Japanese poet Yosa Buson (1716ÃÂÃÂ1784) expressed some of this feeling in a famous haiku:
I cannot see her tonight.
Most Japanese cities have one or more fugu restaurants. A famous restaurant specializing in fugu is Takefuku, a restaurant in the Ginza district in Tokyo.
Few restaurants in the United States carry "fugu." When served in the United States, it typically does not contain any tetrodotoxin. Though taken from the same fish, it does not produce any of the sensations for which it is famous.
There is a fugu museum in Osaka.
Lanterns can be made from fugu, these are occasionally seen outside of fugu restaurants, as children toys, or as folk art and souvenir.Consumption
Fugu Poisoning
Social Aspects
I have to give her up
So I will eat fugu.Availability
Miscellaneous
| Species (Old Names) | Author | Common Name | Distribution | Max. Size | Comments |
|---|---|---|---|---|---|
| Takifugu alboplumbeus (Tetrodon alboplumbeus) | Richardson, 1845 | Komon-damashi (Japan) | West Pacific | 23cm | Poisonous, Salt Water |
| Takifugu basilevskianus | Basilewsky | Darkgreen Puffer, Sansaifugu (Japan) | ? | ? | ? |
| Takifugu bimaculatus (Tetrodon bimaculatus) | Richardson, 1845 | Futatsuboshi-fugu (Japan) | Northwest Pacific | 30cm | Poisonous |
| Takifugu chinensis* (Sphoeroides rubripes chinensis) | Abe, 1949 | Eyespot Puffer, Karasu (Japan) | Northwest Pacific | 55cm | Poisonous |
| Fugu coronoidus* | Ni & Li, 1992 | 暈環多紀魨 (China) | Northwest Pacific | ? | Not poisonous |
| Takifugu chrysops* (Tetrodon chrysops) | Hilgendorf, 1879 | Red-eyed Puffer, Akamefugu (Japan) | Northwest Pacific | 20cm | Poisonous |
| Takifugu exascurus (Spheroides exascurus) | Jordan & Snyder, 1901 | Mushifugu (Japan) | Northwest Pacific | 15cm | poisonous |
| Takifugu flavidus | Li, Wang & Wang, 1975 | Towny Puffer, Sansaifugu (Japan), Hwang-jom-pok (Korea), JÃÂú hÃÂúng dong fang tÃÂún (China) | Northwest Pacific | 35cm | Poisonous |
| Takifugu niphobles* (Spheroides niphobles) | Jordan & Snyder, 1901 | Grass Puffer, Starry puffer, Kusafugu (Japan), CÃÂá NÃÂóc sao (Viet Nam) | Northwest Pacific | 15cm | Poisonous |
| Takifugu oblongus (Tetraodon oblongus, Tetrodon oblongus, Torquigener oblongus, Sphoeroides oblongus | Bloch, 1786) | Oblong blow fish, Lattice blaasop (India), Bebo (India) Buntal (Malaysia), Pita-pita (Indonesia), Ruitjies-blaasop (South Africa) | West Pacific | 40cm | Not Poisonous |
| Takifugu obscurus* (Sphoeroides ocellatus obscurus) | Abe, 1949 | Obscure Puffer, Mefugu (Japan) | Western Pacific | 40cm | Poisonous |
| Takifugu ocellatus (Tetraodon ocellatus) | Linnaeus, 1758 | Ocellated Puffer | Asia | ? | not poisonous |
| Fugu orbimaculatus (Takifugu orbimaculatus) | Kuang, Li & Liang, 1984 | 圓斑多紀魨 (China) | Asia | ? | not poisonous |
| Takifugu pardalis* (Tetraodon pardalis) | Temminck＆Schlegel,1850 | Panther puffer, Higanfugu (Japan), Chol-pok (Korea), 'BÃÂào wÃÂén dong fang tÃÂún'' (China) | Northwest Pacific | 30cm | ? |
| Takifugu poecilonotus* (Tetraodon poecilonotus) | Temminck & Schlegel, 1850 | Fine Patterned Puffer, Komonfugu (Japan), Huin-jom-pok (Korea), Ban dian dong fang tÃÂún (China) | Northwest Pacific | 20cm | Poisonous |
| Takifugu porphyreus* (Tetraodon porphyreus, Fugu vermiculare porphyreum, Fugu vermicularis porphyreus, Spheroides borealis) | Temminck & Schlegel, 1850 | Purple Puffer, Namera-fugu (Japan), Mafugu (Japan), Kom-pok (Korea), Zi sÃÂè dong fang tÃÂún) (China) | Northwest Pacific | 52cm | Poisonous |
| Takifugu pseudommus (Lagocephalus pseudommus, Takifugu pseudomus) | Chu, 1935 | Nameradafugu (Japan), Nameradamashi (Japan) | Northwest Pacific | 35cm | Poisonous |
| Takifugu radiatus (Sphoeroides vermicularis radiatus) | Abe, 1947 | Nashifugu (Japan) | Northwest Pacific | 20cm | Poisonous |
| Takifugu reticularis | Tien, Chen & Wang, 1975 | Reticulate Puffer, Amime-fugu (Japan) | Northwest Pacific | 29cm | ? |
| Takifugu rubripes* (Tetraodon rubripes, Sphaeroides rubripes, Fugu rubripes rubripes) | Temminck & Schlegel, 1850 | Torafugu (Japan), Tiger Puffer, HÃÂóng qÃÂàdong fang tÃÂún (China), Cha-ju-pok (Korea) | Northwest Pacific | 70cm | Poisonous, Used in Chinese Medicine, Genome sequenced completely |
| Takifugu snyderi* (Fugu vermicularis snyderi) | Abe, 1988 | Shosai-fugu (Japan) | Western Pacific | 30cm | Poisonous |
| Takifugu stictonotus* (Tetraodon stictonotus) | Temminck & Schlegel, 1850 | Spotback, Spottyback Puffer, Gomafugu (Japan) | Northwest Pacific | 35cm | Poisonous |
| Takifugu vermicularis (Tetraodon vermicularis, Spheroides abbotti) | Temminck＆Schlegel, 1850 | Pear Puffer, Shosaifugu (Japan), , Nashifugu (Japan), Kuk-mae-ri-bok (Korea), ChÃÂóng wÃÂén dong fang tÃÂún (China) | Northwest Pacific | 30cm | Poisonous |
| Takifugu xanthopterus* (Tetraodon xanthopterus) | Temminck & Schlegel, 1850 | Yellowfin puffer, Shimafugu (Japan), Kka-ch'i-pok (Korea), TiÃÂáo wÃÂén dong fang tÃÂún (China) | Northwest Pacific | 50cm | Poisonous |
Blowfish is also an encryption algorithm.See also
External Links