Are green beans "not suitable" for the table? Doctors teach you the secret of "non-toxic dry rice"

Recently, Luzhou, Sichuan issued the "Luzhou Rural Collective Dining Food Safety Management Standards", among which the new regulation "shall not use wild mushrooms, green and sprouted potatoes, fresh raw chrysanthemums, green beans and other high-risk food raw materials" has aroused heated discussion.

"I have been eating green beans all my life, why can't I use them in banquets?" Many netizens questioned. At the same time, "Green beans are not allowed to be used in rural banquets" became a hot search.

Can green beans also cause poisoning? Experts from the Department of Clinical Nutrition at the Second Affiliated Hospital of Fujian Medical University explain the reason and guide how to eat green beans safely.

French beans, also known as beans and lentils, are common vegetables on the table. They contain dietary fiber, B vitamins and a variety of minerals. They are loved by people for their crisp taste and rich nutrition. So, why is French beans suddenly "blacklisted" when it is obviously a home-cooked dish?

"Indeed, seemingly healthy green beans can cause food poisoning if not handled properly." Ke Zhiyuan, director of the Clinical Nutrition Department of Fujian Medical University Second Hospital, said that there are cases of food poisoning due to eating green beans every year in China. Patients may experience symptoms such as nausea, vomiting, abdominal pain and diarrhea within 30 minutes to 2 hours after eating. Severe cases may even require emergency medical treatment due to dehydration and low blood pressure.

Why are green beans so poisonous?

Director Ke Zhiyuan said that the root cause of green bean food poisoning is that it contains toxic ingredients, mainly saponins, hemagglutinins and cyanogenic glycosides. These substances may cause acute gastrointestinal reactions and lead to poisoning symptoms if they are not fully heated .

Saponins: are plant compounds with foaming properties that can damage the cell membranes of the human intestine, irritate the digestive system, and cause nausea, vomiting, and diarrhea. However, saponins are temperature sensitive and are destroyed by high-temperature cooking.

Hemagglutinin: A protein that causes red blood cells to agglutinate, widely found in leguminous plants. It can be inactivated by heating above 80°C for 10 minutes, but if the heating temperature is insufficient or the heating time is too short, it may still cause poisoning symptoms such as stomach discomfort, nausea and diarrhea.

Cyanogenic glycosides: After being metabolized in the body, they release cyanide, which affects the oxygen metabolism of cells, causing fatigue, dizziness, and even breathing difficulties. However, the content of cyanogenic glycosides is relatively low, and their toxicity can generally be removed by sufficient heating.

This is the safest way to eat beans

If you want to enjoy green beans safely in your daily home cooking and avoid food poisoning, you need to keep the following principles in mind:

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Fully heated

Green beans must be thoroughly heated to 100°C and kept for at least 10 minutes to completely destroy their harmful ingredients. When cooking, it is recommended to blanch the green beans in boiling water for 5 to 10 minutes before frying them to ensure that the inside of the green beans is thoroughly cooked. In addition, steaming for more than 15 minutes can also effectively remove harmful substances, while slow frying at low temperature or heating in water may not meet safety standards and should be avoided as much as possible.

Avoid cold salad

It is important to note that green beans are not suitable for cold dishes or salads. Even if the color of the surface changes, it does not mean that the inside has been fully heated to a safe temperature.

Do not eat raw

Usually, the color of cooked green beans will change from bright green to dark green, the texture will become softer, and the taste will no longer be raw and astringent. If the green beans are still hard or astringent after frying, it means they are not fully cooked, and it is recommended to continue heating.

Experts advise

"Symptoms of green bean poisoning usually appear within a short period of time after consumption. Mild patients may only experience stomach discomfort, while severe cases may experience dehydration, low blood pressure, and even affect the nervous system." Director Ke Zhiyuan further pointed out that green bean poisoning usually does not cause long-term health harm, and the symptoms are usually relieved within 24 hours, but for children, the elderly and those with low immunity, once symptoms of poisoning appear, please seek medical attention and be hospitalized for observation in time, and receive fluid replacement therapy to prevent dehydration from worsening the condition.