Why does Chang Xia eat salted eggs?

The long summer is coming. It means that spring is over and summer is coming. In order to welcome the arrival of summer, Hangzhou people have prepared 12 kinds of food. There is a song that says: "Summer cakes, river fish and black rice cakes, sour plum and broad bean cherries, bacon, roasted goose and salted duck eggs, snail and amaranth" are mostly "fresh" foods. Take salted duck eggs as an example. It's the egg when the duck just entered the water this year, and the salted duck egg has been marinated until now. Su Dongpo said: Spring River Plumbing Duck Prophet. The solar term suitable for ducks to enter the water is probably "rain". It's been more than a month since the long summer rain. The salted duck eggs have been preserved and are fresh. Furthermore, from a medical point of view, duck eggs are cool, sweet and salty, and have the effects of nourishing yin, clearing away lung heat, nourishing heart and stopping heat, so eating salted duck eggs in long summer is also called "chewing summer".