Pingjiang bean products have a long history, unique flavor and long-standing reputation. Since ancient times, people in Pingjiang have been taking soybeans as their main crops. The legume carbides unearthed in Zhong Xian and Chiayi County prove that soybean planting in Pingjiang has a history of more than 2,000 years, and there are detailed records of soybean planting in Pingjiang County Records in Yihai period (AD 1755).

"Duozhen Dry Sauce" was renamed "Spiced Dry Sauce", which is a famous specialty of Pingjiang. Because of its rich sauce flavor and endless aftertaste, it has been a tribute in all dynasties.

Pingjiang sauce is a specialty of Longevity Street, an ancient town near the Miluo River. With a long history and unique flavor, it is the favorite of Zeng Guofan, who was led by Xiang Army in Qing Dynasty. Of course, there are many versions about the origin of dried sauce circulating among the people: there is a saying that after eating it privately, it becomes a famous Hunan flavor food; In the Qing Dynasty, Hunan students came to Beijing to take the exam. During the court exam, they talked about the specialties of Sanxiang, especially the dried spiced sauce. When the emperor heard about it, he paid tribute. After the son of heaven tasted it, he was very happy. He often rode a fast horse of 800 Li and sent it all the way day and night. There is a saying that when the Ming emperor Zheng De passed by Changshou, he ate it and handed it to him as a tribute. There is also a Pingjiang folk song as proof: "The south bank worships Beidou, and Zheng De walks the world. Wear a melon spoon on your head and step on the door of the stove. "