Suan cai

Suancai is a traditional Chinese pickled Chinese cabbage (napa cabbage) or Chinese mustard, used for a variety of purposes. Suancai is a unique form of paocai, due to the ingredients used and the method of production. In China, the earliest record of Chinese traditional Suan cai production is in the Book of Odes (or Classic of Poetry), dating back to 11th to 7th centuries BC. During that time period, fermented vegetables were used as a sacrifice in the worship ceremony of ancestors. In the poem Xin Nan Shan (Chinese: 信南山; pinyin: xin nan shan), there is a description of how the ancient Chinese produced suan cai by pickling gourds:

Source: Wikipedia