Death from fermented food
Some fermented foods may carry the risk of contamination with bacteria that produce an extremely potent toxin called bongkrekic acid.
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I only became interested in fermented foods a few years ago. I used to not even like yogurt, but now I eat it almost every day – and always enjoy eating miso and sauerkraut. Many nutritional guides state that I'm doing something good for my body.
In most cases this may well be true. But some fermented foods harbor a bacteria that produces an extremely powerful toxin called bongkrekic acid. It accumulates unnoticed in food and causes dangerous food poisoning in anyone who eats it, as shown by The outbreak occurred in October 2020 in a city in eastern China..
Twelve people had breakfast together at home. Nine of them were dead over the next two weeks. They all had one thing in common: they ate sour soup. The dish contained noodles that the owners had made from fermented corn (which had been stored too long and too carelessly). It took only a few hours for the poisoning victims to show the first symptoms. First they noticed abdominal pain, nausea and vomiting. Some developed diarrhea and all of them quickly became very ill. The symptoms became so severe that they sought medical attention that same day. However, doctors could not help them. The first patient died just 20 hours after symptoms of poisoning appeared. Six more followed in the next 48 hours. The last two survived a few days longer, but they also did not recover from the disease, in which case all the people who ingested the toxin died.
Overall, approx. half of such encounters with bongkrekic acid are fatal. Even the smallest amounts of a substance – from one to one and a half milligrams – can cost an adult his life. In the reported tragedy, Chinese authorities found a concentration of 330 milligrams per kilogram in the homemade noodles that the victims ate. Assuming consumption is around 100 grams per person, this is approximately 20–30 times the lethal dose of poison.
Cooking didn't matter. Unlike the bacteria that produce bongkrek acid, the substance itself does not decompose when cooked. And neither the taste nor the smell of the dish indicate its presence.
Although the corn drug was a failure here, boncrecic acid was initially associated primarily with another food product. The toxin was even named after him: Tempe Bongkrek. Tempeh is made from fermented soybeans. After soaking and cooking the beans, mold spores are added and the mixture is left to ferment for about two days in an airtight container. The resulting mass of plants and mushrooms can then be seasoned and sautéed or deep-fried.
Apart from soy, tempeh bongkrek also contains coconut meat as an additional ingredient. AND Burkholderia gladioli a bacterium that can produce bongkrek acid prefers to grow in this pulp. More precisely, it is a special strain of this bacterium that produces a particularly large amount of toxin. Burkholderia gladiolus pathovar cocovenenansor B. cocovenanance Briefly speaking. Because consumption of tempeh bongkrek in Indonesia led to thousands of cases of poisoning, the country's government was forced to ban its production in 1988. But just as the Germans did not allow their sauerkraut to be taken away from them, the same can be said about temp bongkrek. Even today, people still produce it for personal use or for the black market.
B. cocovenanance likes to grow on moist, starchy grains if they start to ferment – either intentionally or due to improper storage. In addition to fermented corn products, these products may include sweet potato flour and rice noodles blamed for some outbreaks in China.
Although cases remain concentrated in Southeast Asia, in 2018, the disease also appeared for the first time in Africa. From January 9 to 12, 234 people in Mozambique fell ill after drinking Pombe, a traditional drink made from corn flour. A total of 75 people died from poisoning.
And in 2024 there was a case in North America. The victim prepared a dish using fermented cornmeal. When he went to hospital two days later, he complained of nausea, vomiting and fatigue. By this point, his liver and kidneys were already seriously damaged, and his blood was acidic. His condition steadily worsened over the following days and he died in hospital eight days later. No cases of bongkrecic acid poisoning have yet been reported in Europe, but it cannot be ruled out that B. cocovenanance will appear there at some point.
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This article originally appeared in spectrum of science and reproduced with permission.
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