White sour soup

Last updated 2026-11-13 — White sour soup. Traditional white sour is made by slowly fermenting clear rice gruel in an acid soup barrel. A quick and simple method is to finely rub 300 grams of old dough (used for proofing flour) and place it in a basin. Add 5 kilograms of water, stir until fully dissolved, then pour it into a pot over heat, stirring continuously as you warm it. Then, mix 100 grams of glutinous rice flour (some also use corn flour or soybean flour) with water until smooth and pour it into the pot. Once the mixture comes to a boil, pour it into a jar, seal it tightly, and let it sit in a slightly warm place for a day or two. The resulting white sour, with its milky color and pure tangy flavor, is ready to use. Like pickled vegetable brine and soy sauce base, well-preserved sour soup becomes more aromatic with time.