Baoning Prefecture (now Langzhong City) began to brew vinegar in the Shang and Zhou Dynasties and flourished in the Qin and Han Dynasties. In 936 AD during the Five Dynasties and Later Tang Dynasty, it was named Baoning vinegar because of the establishment of Baoning Military Government. Later, the formula was improved by Suo Yiting, a master of brewing vinegar in the court of the late Ming Dynasty, and it became famous after adding Chinese medicine to make koji, becoming the standard for brewing bran vinegar in the southwest. In the Tang Dynasty, Dinggang vinegar workshops were all over the market, and the vinegar industry was prosperous. Although there are many vinegar workshops in Langzhong, the most famous one is Baoning vinegar, which started in 936 AD and has a history of more than 1,000 years. In the late Ming and early Qing Dynasties, Suo Yiting, a court vinegar master, chose to live in Langzhong, integrated the original craftsmanship of Baoning vinegar with court techniques, and innovatively used dozens of Chinese medicines such as white koji, amomum, eucommia, angelica, five flavors, and mint to make koji, and took groundwater from the Jialing River to brew bran vinegar. The vinegar liquid is reddish brown in color, mellow and sweet, with a soft sour taste, and it will not rot for a long time. Since then, its reputation has risen rapidly and it has become the standard for brewing vinegar, which is unique in the Chinese vinegar garden. During the Qianlong period of the Qing Dynasty, Suo Shaowu, the fifth-generation grandson of the Suo family, standardized the medicinal koji formula and brewing process of Baoning vinegar. So far, Suo's vinegar industry has become increasingly prosperous with the characteristics of medicinal koji and bran vinegar, and has become famous in Yunnan, Guizhou, Sichuan, Shaanxi and Gansu, and has entered the list of the four famous vinegars in the country. After liberation, the state authorized Baoning Vinegar Company to exclusively manage the formula of Baoning vinegar. For a long time, the process and formula of Baoning vinegar have only been in the hands of the company's core personnel, which effectively ensures the purity of the traditional quality of Baoning vinegar. In the process of hundreds of years of inheritance and development, Baoning vinegar has become a century-old brand with bran vinegar and medicinal vinegar as its characteristics through continuous exploration and innovation. From winning the gold medal at the Panama World Expo in 1915, to being selected as a national banquet product in 1985, to the establishment of Sichuan Baoning Vinegar Co., Ltd. in 1994. Baoning vinegar originated in 936 AD. After thousands of years of polishing and precipitation, with its open mind and openness, it has continuously accepted, integrated and improved the brewing skills and taste of Baoning vinegar. It was eventually praised as the spirit of Sichuan cuisine. There is even a saying that "Sichuan cuisine will not be popular without Baoning vinegar". The core of traditional Baoning vinegar brewing is Chinese medicine koji making and wheat bran vinegar brewing. Baoning vinegar is brewed through 42 processes, and the core processes are koji making, fermentation, vinegar pouring, blending, boiling, filtering and aging.