by Janet Spencer
Come along with Tidbits as we nibble some of the world’s most questionable foods!
• Cassava, also called manioc, is a tropical plant whose starchy tuberous root is similar to the yam. It’s the source of tapioca. It’s the third most important source of calories for people in the tropics, after rice and corn.
• Cassava is edible, but there’s a catch: the root tubers contain a substance called linamarin that triggers the production of cyanide within the body after being ingested due to its interaction with bacteria in the gut. There are two types of cassava: sweet cassava, and bitter cassava. Sweet cassava contains only a small amount of linamarin whereas bitter cassava contains almost ten times more.
• Sweet cassava is safe to eat after being boiled, which destroys the linamarin. But bitter cassava must go through a long process of peeling, grating, drying, soaking in water, fermenting, boiling, rinsing, and cooling before it is safe.
• Depending upon the amount eaten, ingesting linamarin casues rapid respiration, a drop in blood pressure, rapid pulse, dizziness, headache, stomach pain, vomiting, diarrhea, mental confusion, twitching, convulsions, and sometimes death.
• Pufferfish is perfectly safe to eat, if only you avoid the poisonous parts: the eyes, ovaries, intestines, liver, blood, and the spikes in the skin. The problem is that if the toxic parts have even the slightest contact with the flesh of the fish, such as when a knife slices through, just that much of the poison can kill a person.
• The poison is called tetrodotoxin. It’s 1,200 times more potent than cyanide. It is so potent that a lethal dose is smaller than the head of a pin, and a single fish has enough poison to kill 30 people.
• Pufferfish ingest bacteria that produce this toxin, but the fish are immune to it. The toxin concentrates in specific organs, but the muscle of the fish is perfectly safe.
• The dish is called fugu, which is the Japanese word meaning “to blow” referring to the ability of the pufferfish to expand in size by ingesting sea water, blowing up like a balloon when threatened.
• Professional chefs must undergo a three-year program of training to be allowed to prepare and serve fugu in restaurants. Because it’s so labor-intensive, a single dish of fugu might cost up to $200.
• Most of the deaths due to fugu poisoning come from untrained people trying to prepare it at home. The poison is a powerful neurotoxin which paralyzes the muscles while the victim remains entirely conscious. Eventually the victim is unable to breathe and dies of asphyxiation. There is no anecdote. However, people have survived by being placed on life support systems until the poison wears off. About 50 people per year suffer from fugu poisoning, and an average of 7% of them die.
• Recently, fish farmers have begun raising poison-free fugu by keeping the fish in tanks that are free from the toxic bacteria.
• The bodies of animals living underwater are subjected to great amounts of pressure from the weight of the water. This pressure distorts protein molecules, which would normally kill the animal. Sea creatures evolved to create a defense mechanism, called trimethylamine oxide, or TMAO. TMAO is a chemical compound that acts as a pressure-resistant protein stabilizer. It allows protein molecules to retain their flexibility, letting ocean creatures live at great depths. Fish, mollusks, and crustaceans all contain it in their tissues. The deeper the animal lives, the greater the amount of it they have. When fish die and decay, it’s the TMAO that causes the odor of rotten fish.
• Greenland sharks live at great depths. Their lifespan can top 500 years. Their bodies are packed with high levels of TMAO.
• TMAO is poisonous to humans. Small amounts of TMAO such as what’s in crab or scallops or cod don’t affect humans that eat these animals. But large amounts, such as what’s found in Greenland sharks, can cause extreme intoxication, intestinal distress, neurological effects, and can sometimes lead to death.
• Then, too, consider the fact that Greenland sharks don’t have a urinary tract, so waste and toxins are filtered through their skin and flesh. For the shark, this mixture of compounds acts as a natural antifreeze that protects it from the frigid arctic waters. But it does tend to give their meat a very strong odor and a very peculiar taste.
• Does any of this prevent people from eating Greenland shark? Heck no! Trimethylamine oxide can be neutralized by leaving the fish to rot. This is an art the Vikings perfected, in a dish called hákarl, from the old Norse word meaning “shark.” Hákarl is basically fermented shark meat.
• Here’s the recipe for hákarl: bury the shark meat under sand and gravel, with stones on top to press the fluids out. Leave it for six to 12 weeks, depending on the season. Next, hang the meat to dry for several months. Prior to serving, scrape the crust from the flesh, then cut into bite-size chunks and serve on a toothpick. Hold your nose while swallowing in order to avoid the strong odor of ammonia. Keep in mind that if the shark meat has been improperly prepared, your dinner guests will need a quick trip to the hospital to recover from the experience.
• Noted chef Anthony Bourdain famously said that hákarl was “the single worst, most disgusting and terrible tasting thing” that he had ever eaten.
• It’s officially the national dish of Iceland, and Greenlanders enjoy it as well.
BAD FOOD FACTS
• The following are the most dangerous foods in terms of passing on foodborne illnesses: Raw or undercooked meat and poultry; raw or lightly cooked eggs; unpasteurized milk, cheese, and other dairy products; seafood and raw shellfish; unwashed fruits and vegetables; raw flour; and sprouts, such as alfalfa and mung bean.
• What is the deadliest food poisoning? Salmonella. About 1 million people are sickened by salmonella in the U.S. each year and around 380 of them die from the infection. Children are at the highest risk for salmonella infection. Kids younger than 5 have higher rates of salmonella infection than any other age group.
• The most common food allergies are: milk; eggs; seafood; tree nuts; peanuts; wheat / gluten; soy. These account for about 90% of all food allergies.