The main component of salt is sodium chloride, too early to put salt, under the action of heating will be decomposed, but also accelerate the destruction of the nutrients in the soup. It is recommended to add salt only after the soup is almost ready. (It should be put salt when the fire is almost off, because, too early to put salt, in the soup is not yet cooked, the water is easy to boil dry, the taste will become salty, not only to accelerate the destruction of the nutrients in the soup, but also to destroy the taste of the soup, too late to put salt will lead to the soup inside the material to absorb not enough salt is not enough to taste, and the salt is not too easy to be decomposed, so, in the soup just about to be almost ready to cook for 10 minutes or so to put the salt is the most appropriate.)