There are more than 70 varieties of pineapple. There are two kinds of pineapples and pineapples on the market. Although they are similar in appearance, they still have a little difference. If they are not professionals, they are generally not very clear. The difference, but after peeling is very good to distinguish, because pineapple peeling there are some internal barb, so many peeled pineapple is spiral, is to remove the excess barbs, and pineapple Without those barbs. Pineapple is rich in nutrients, there are a lot of glucose, fructose, multi-vitamins, trace elements, but also contains citric acid and protease, but before the pineapple needs to be soaked in salt water, why is this? Why does pineapple soak in salt water? How long is it? We all love to eat pineapple, but every time we eat pineapple before the invention we must use salt water to soak, but why pineapple soaked with salt water? Pineapple need to use brine for how long? Pineapple also has a special health-care ingredient called "Bromelain," which promotes the breakdown of proteins such as meat and helps in weight loss. Moreover, studies have shown that bromelain can not only inhibit the growth of tumor cells, but also ease arterial contraction, relieve angina, and have a certain effect on cardiovascular disease. However, whether Xiao Cheng and Xiao He also lost, pineapple's greatest health taboo comes from this "brownine." Bromelain can digest proteins, increase the permeability of the gastrointestinal mucosa, increase the sensitivity of humans to foreign bodies, and aggravate the occurrence of allergic reactions. Some people will experience dizziness, vomiting, abdominal pain, diarrhea and other symptoms after eating pineapple, which is an allergic reaction caused by bromelain. As long as bromelain is soaked in salt water, its protein structure will be destroyed, thus reducing the incidence of allergic reactions. In addition, the pineapple stimulants on the skin and oral mucous membranes have a stimulating effect, if you eat raw pineapple or untreated pineapple, lip and mouth corners will have a tingling tingling feeling, that is, the reason why the steroid material. Saltwater soaking not only removes the moss in the pineapple, but also dissolves the organic acids, making the pineapple taste sweeter. It's best to soak your pineapple for half an hour. You can avoid all the above problems and make the pineapple more sweet. In addition, pineapple also contains oxalic acid, will affect the body's absorption of calcium and iron, soaking with salt will neutralize its acidity, reduce the harm that may be to the body. Finally, if the fruit of the pineapple suddenly protrudes at the top, the peel will turn yellow, indicating that it has reached nine maturity. This kind of pineapple juice has many high sugar content and strong flavor. If it is not rushing to eat, it is best to choose the body is still hard, light yellow with a green luster, about 78 ripe.