Soak the pineapple in salt water for a while, and the pineapple will gradually become sweet! Although pineapple is rich in sugar, protein and vitamin C, it has the functions of clearing away heat and relieving summer heat, promoting fluid production to quench thirst and inducing diuresis. But pineapple also contains glycosides, bromelain and 5- hydroxytryptamine, which can stimulate the young epidermis of our oral mucosa and lips and make us tingle. Salt can inhibit the activity of pineapple enzyme. Therefore, when we eat fresh pineapple, it is best to soak it in salt water for a period of time, which can inhibit the stimulation of pineapple enzyme on our oral mucosa and lips, and at the same time feel that pineapple is sweeter.