Century eggs (Chinese: 皮蛋; pinyin: pídàn; Jyutping: pei4 daan2), also known as preserved egg, hundred-year egg, thousand-year egg, thousand-year-old egg, millennium egg, skin egg and black egg, are a Chinese preserved food product and delicacy made by preserving duck, chicken or quail eggs in a mixture of clay, ash, salt, quicklime, and rice hulls for several weeks to several months, depending on the method of processing.Through the process, the yolk becomes a dark green to grey color, with a creamy consistency and strong flavor due to the hydrogen sulfide and ammonia present, while the white becomes...