Tangchi old sauce is a specialty of Yiliang County in Yunnan Province and has a long history. As early as in the Ming Chongzhen years, the folks in Tangchi Town prevailed in the folk customs of steaming old sauces. The sauce shops opened by the ancestors of the Zhao family were the most famous. During the Qing Dynasty, the old sauce of the "Zhao's Sauce House" in Tangchi was tribute to the capital of Yunnan by the government officials, and was dedicated to the emperor. It was listed as a court tribute. Today's "Yiliang County Yuquan Food Factory" was created by the descendants of Zhao's Sauce Factory.