Due to the pressing method required to squeeze out the water in vegetables during processing, it is called "mustard".

No matter which method is used, authentic mustard must be salted and pressed three times, which is why the mustard gets its name. Mustard is a semi-dry, non-fermented pickle made from pickled mustard stems. It is one of China's famous specialty products, and is one of the world's three most famous pickles along with French sour cucumber and German sweet and sour cabbage. It first appeared in Fuling, Sichuan, China (now Fuling District, Chongqing City) in 1898, and was called "Fuling mustard" at that time.

Extended information:

During the Guangxu period, a businessman named Qiu Shouan in Fuling, Sichuan opened a Rongchang soy sauce garden in Yichang, Hubei, and also dealt in Sichuan kohlrabi, but the business was slow.

Later, Deng Bingcheng, a native of Zhongxian County, Sichuan, was hired as a pickle technician in his hometown of Fuling. Deng Bingcheng was smarter as an adult. He pickled the fat and tender green cabbage heads into mustards and sent them to Yichang. Boss Qiu thought it was good, so he set up People were invited to taste mustard at the banquet, and everyone was full of praise after tasting it. So Rongchang Sauce Garden started selling mustard.

Rongchang Sauce Garden’s business has been booming since then. Because the pickling process of mustard must go through multiple processes such as air drying, dehydration, pressing with wood, and dewatering, it is named mustard. Today, there are two major bases for mustard production across the country, one in Sichuan and the other in Zhejiang.

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