What is a century egg?

Also known as the preserved egg or the thousand-year-old egg, the century egg is considered a delicacy in parts of China, where it originated.  It is characterized by a white that has turned completely black (or in some cases a translucent brown) and a greenish-gray yolk that is considered to have a “creamy” consistency.  It has a strong ammonia-like smell due to the high level of alkalinity; many people liken the odor to that of smelly cheese.


How is it made?

The century egg was traditionally created by taking fresh, raw chicken, duck, or quail eggs (duck eggs are preferred) and packing them in a pasty mixture of water, alkaline clay, ash, lime and salt.  The mixture hardened, and the coated eggs were left for several weeks to several months, during which time the pH rose to 12 or more and both preserved and, in a way, “cooked” the eggs.


Although in many parts of China the traditional method is still the most popular, a better understanding of chemistry has allowed for the creation of a simplified method that yields the same results.  One modern method involves soaking the eggs in a mixture of salt, calcium hydroxide, and sodium carbonate for ten days and then aging them for an additional several weeks wrapped in plastic.


I want to try this - how do I get it?

While this type of egg can obviously be made at home, it requires the purchase of caustic ingredients such as quicklime, so for your safety this writer recommends purchasing pre-made century eggs at your nearest Chinese grocery store.


How do you eat it?

The egg is usually sliced up and included in dishes such as soup and congee (rice breakfast porridge), rather than eaten alone. 


What does it taste like?

Many people find that the white has very little flavor to it and that the yolk is slightly bitter.


Eggs are one of the world’s most versatile foods – they can be pickled, scrambled, boiled, fried, and poached.  But when it comes to strangeness, the century egg takes the cake.  Strangeness aside, this Chinese delicacy deserves respect, as it has survived as an important part of Chinese cuisine for over 600 years.