Qing Tuan is a special kind of food, also called Ai Tuan and Qing Guo Ming, which is mainly popular in southern Anhui, southern Jiangsu, Zhejiang and Shanghai. According to textual research, the "Youth League" was once a sacrifice used by Tomb-Sweeping Day to worship his ancestors, which originated in the Tang Dynasty. After 1000 years' development, the form of "Youth League" has not changed much, but the application scene has changed from sacrifice to special snacks in people's daily life.

The green of "Youth League" was originally taken from green plants, such as wormwood, Maggotia, Hu Cai and Rodent. It is best to use wormwood before and after Tomb-Sweeping Day, because its leaves are tender and green. When making "green balls", green plants such as the tender leaves of wormwood should be put into a large pot and steamed with lime, then the lime water should be removed to make "green slurry", then the "green slurry" and glutinous rice flour should be kneaded into green dough embryos, and finally the green dough can be made by kneading the stuffing into balls.