Because there is an endotoxin in beans, it needs high temperature to be destroyed, so it must be heated to boiling enough, or heated in a hurry for more than 10 minutes to ensure that the long beans are cooked thoroughly, so that it will not affect health when eaten. After boiling beans for 5 minutes, the saponin yield reaches the highest point, and then it will gradually weaken. Boil for 20 minutes, and the toxins in the beans will disappear completely.

Method for judging maturity of beans

1, the color darkens.

Generally, raw beans are mostly light green in color. When the beans are cooked, the color will turn dark green. If all the beans turn dark green, it means that the beans are almost ripe.

2. The taste becomes soft

Taste the beans carefully. If they are not cooked, they will taste beany, while fully cooked beans will taste soft and have no beany.