Mature vinegar paste in Taiyuan, capital city of North China's Shanxi province, has been preserved for more than 30 years.

In this video, a staff member at Donghu Vinegar Garden shows mature vinegar paste.

It took five procedures - braising, fermenting, fumigating, filtering and preserving - to create the product. The whole process is natural fermentation without adding any chemicals.

The price of the product can reach 1,288 yuan ($186.3) per 250 grams. With over 3,000 years of history, Shanxi mature vinegar, one of the four famous vinegars in China, is made from sorghum, barley and other raw materials.

[Video by Zhao Gaoyuan and Li Jianzhou]