The Chinese character for sour (pinyin suan) contains a bottle-like element that is sometimes translated wine, sometimes whiskey bottle, and sometimes “the tenth of the twelve earthly branches,” whatever that means. The bottle-like element appears in the character for alcoholic beverage, the character for vinegar, and several other characters with no obvious connection to fermentation. But the connection between sour and fermentation is clear.
My belief that we need to eat lots of fermented food to be healthy began when I realized that would explain why we like sour foods, foods high in umami, and foods with complex flavors — preferences I’d never heard explained. We like those foods, I theorized, so that we will eat foods high in bacteria. Bacteria tend to make sugar-containing foods sour, protein-containing foods high in umami, and all foods high in flavor complexity. I had not previously connected sourness and bacteria — but the Chinese had. I don’t yet know the Chinese characters for umami or flavor complexity.