Eating half-baked beans may cause bitterness in the mouth. This is because beans contain a substance called saponin, which is toxic to human body if it is not cooked thoroughly. Saponins will decompose at high temperature, but if they enter the human body undercooked, they may stimulate the gastrointestinal tract and cause nausea, vomiting, abdominal pain, diarrhea and other symptoms. At the same time, it may also cause discomfort such as bitter taste and numbness of the tongue.

Therefore, in order to ensure health, beans should be thoroughly cooked before eating. Generally speaking, saponin in beans can be destroyed by high-temperature cooking, thus avoiding the above uncomfortable reactions. It is recommended to cook beans for a period of time to ensure thorough cooking and avoid health problems caused by eating undercooked beans.