green beans, also known as kidney beans, kidney beans or lentils, are common leguminous vegetables in the south. Green beans contain a toxic component saponin, which is mainly concentrated in the beans of green beans.

Saponin is a substance that can cause poisoning. It can stimulate inflammation of gastrointestinal mucosa, and it also has hemolytic effect. It can easily enter red blood cells in the blood, destroy red blood cells and cause hemolysis. Therefore, we should try to make its toxicity disappear when eating. Because saponin is decomposed and destroyed at high temperature and loses its toxicity, as long as it is cooked thoroughly during cooking, there will be no problem.

However, if the beans are not cooked and the saponins in the beans are not decomposed and destroyed, people may be poisoned after eating them. For example, in a school somewhere, more than 6 people were poisoned by eating this kind of uncooked green beans.

The experiment proved that the green beans were soaked in boiling water for 2~5 minutes, then fried until the green color disappeared, and all the saponins in the beans were decomposed and destroyed. Therefore, to eat green beans, you should cut them into pieces, first soak them in boiling water, and then cook them thoroughly. It is advisable to eat them without taste or bitterness.