Century egg is a Chinese delicacy made by preserving duck, quail, or chicken eggs in a saline solution that consists of salt, clay, and sometimes ash, quicklime, or rice hulls. The solution causes the yolk to develop a creamy texture, and it changes the egg whites into a dark-colored, jelly-like substance.

The dish is thought to have originated during the Ming Dynasty period in Hunan, when a farmer found duck eggs in a pool of slaked lime and decided to eat them. Afterwards, he added salt to the eggs in order to improve the flavor. Today, century egg is often compared to a rich cheese, regarding its sharp scent and flavor, and it is commonly served as an appetizer or a side dish, typically accompanied by rice and pork porridge or pickled ginger root.