Pidan

Pidan, also called thousand-year eggs or century eggs, are duck eggs preserved by months-long curing in an alkaline blend — caustic soda with burnt straw ash and slaked lime. The high pH transforms the proteins: whites turn amber and gelatinous, yolks darken and cream, and a distinctive pungent flavor develops. In food science, pidan demonstrate alkaline preservation, where elevated pH suppresses many spoilage organisms while restructuring texture. Makers control alkali strength and curing time to reach the desired consistency without harsh ammonia notes. Standardized modern production delivers the traditional delicacy with consistent quality and verified safety.