Pineapple directly is likely to skin and oral mucosal irritation symptoms, such as nausea, vomiting, oral numbness and other discomfort. Pineapple contains more glycosides, organic acids and bromelain and other substances, direct consumption of the skin around the mouth, the digestive tract mucous membranes produce more obvious symptoms of irritation, resulting in numbness of the mouth, ulcers, and nausea, vomiting, abdominal pain, diarrhea and other symptoms of discomfort. Some of the more sensitive people may even have an allergic reaction, itchy skin, hives, angioneurotic edema, and even breathing difficulties. Therefore, it is recommended that when eating pineapple soaked in lightly salted water, which glycosides, organic acids and bromelain concentration will be reduced accordingly, but also can enhance the taste of pineapple.