Why can green beans cause poisoning? Green beans, also known as sword beans, kidney beans, lentils, etc., are popular vegetables. It is generally believed that the poisoning of green beans is related to the variety, origin, season, cooking methods and quantity of green beans. The common causes of poisoning are improper cooking and insufficient detoxification, with the most poisoning cases occurring around beginning of autumn to first frost all year round. Raw green beans contain two toxins, namely saponin and hemagglutinin. Because saponin has strong irritation to human gastrointestinal tract, it can cause hemorrhagic inflammation and dissolve red blood cells. In addition, hemagglutinin can agglutinate red blood cells. These two toxins are not terrible. As long as they are heated above 100℃ and the green beans are cooked thoroughly, their toxins will be destroyed. How to prevent kidney bean poisoning? Experts pointed out that the method of preventing green beans poisoning is actually very simple. First, all green beans should be cooked and stewed thoroughly. The amount of green beans processed in the collective canteen should not exceed half of the pot capacity. After frying in oil, add a proper amount of water, add the pot cover to stew for about 10 minutes, and turn the green beans constantly with a shovel to make it evenly cooked by heating. You can also cook with water before frying in oil to ensure safety. Green beans change from hard to soft after being cooked, and the color changes from bright green to dark green. They have no bean smell when eaten. As long as they are cooked and stewed thoroughly, they will not cause poisoning. Second, we should pay attention not to buy or eat old green beans. Before cooking, we should remove both ends of green beans and pods, because toxins are high in the head and tail of pods.