Century Egg Image Used Under Creative Commons License From openrice.com

Citizens, it is a veritable fact that one culture’s delicacy may be perceived as another’s gustatory nightmare. This is the result of a closed mind and a staid palate – perspectives thankfully never darkening the doorstep of TFD Nation!

A perfect example of this are Chinese century eggs – a delicacy beloved by TFD and sought out whenever possible while ill-informed others run screaming in the opposite direction. In this recipe, I will teach you HOW to make these special treats in a modern fashion that dramatically simplifies making what used to be a long, drawn-out recipe process over several months.

Century eggs (Chinese: 皮蛋; pinyin: pídàn), 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, while the white becomes a dark brown, translucent gel with a firm consistency. The transforming agent in the century egg is an alkaline salt, which gradually raises the pH of the egg to around 9–12, during the curing process.

This chemical process breaks down some of the complex, flavorless proteins and fats, which produces a variety of smaller flavorful compounds.

Some eggs have patterns near the surface of the egg white that are likened to pine branches, and that gives rise to one of its Chinese names, the pine-patterned egg. You can see in the post image an example of pine branches – just look closely.

These intricate snow-flake or tree branch-like patterns lie just beneath the surface of the egg whites. The suspended patterns inside the egg are like works of mysterious 3D art -century eggs are sometimes called “Songhua dan” or pine-patterned eggs.

Pine Needle Patterning

There’s no mystery in the science. The patterns are caused by crystalline dendrites of the various alkaline salts in the egg. The more salt there is in the curing solution and the more the temperature changes during the fermentation, the more these patterns will emerge.

The method for creating century eggs likely came about through the need to preserve eggs in times of plenty by coating them in alkaline clay, which is similar to methods of egg preservation in some Western cultures. The clay hardens around the egg and results in the curing and creation of century eggs instead of spoiled eggs.

Not coincidentally, the century egg actually has over five centuries of history behind its production. Its discovery (though not verifiable), was said to have occurred around 600 years ago in Hunan during the Ming Dynasty, when a homeowner discovered duck eggs in a shallow pool of slaked lime that was used for mortar during construction of his home two months before.

Upon tasting the eggs, he set out to produce more – this time with the addition of salt to improve their flavor – resulting in the present recipe of the century egg.

Century eggs can be eaten without further preparation than peeling and rinsing them – on their own, or as a side dish. As an hors d’œuvre, the Cantonese wrap chunks of this egg with slices of pickled ginger root (sometimes sold on a stick as street food). A Shanghainese recipe mixes chopped century eggs with chilled tofu.

In Taiwan, it is popular to eat sliced century eggs placed on top of cold tofu with katsuobushi, soy sauce, and sesame oil, in a style similar to Japanese hiyayakko. A variation of this recipe common in northern China is to slice century eggs over chilled silken (soft) tofu, adding liberal quantities of shredded young ginger and chopped spring onions as a topping, and then drizzling light soy sauce and sesame oil over the dish, to taste.

IMPORTANT: please note that to make these eggs, you’re going to need to take certain precautions – you’ll be working with a dangerous chemical. Don’t freak out, these precautions are just that – precautions.

Specifically, you’re going to be using lye in this recipe. Lye is incredibly dangerous to handle and can cause severe burns with any contact to your skin, and there’s also an inhalation risk. As such, you should wear long gloves and use a respirator to protect yourself. There are plenty of other foods that are made/prepared with lye (pretzels being one), just PLEASE use caution and common sense. Always use pure, 100% lye (sodium hydroxide) – you can buy it here.

Sodium hydroxide is a strong base (the opposite of an acid), so be sure to wear long plastic gloves and be careful not to splash it on your skin, eyes or clothes. Also, you must make sure you NEVER put the sodium hydroxide solution in a glass container. Glass is badly damaged by long exposure to hot sodium hydroxide, and it also frosts the glass.

If you want a respirator to use for short exposure to lye mist and for protection from hazardous or irritating dusts, I would choose a high-efficiency particulate respirator with an “N100” or “P100” rating. This type of respirator removes 99.97% of the dust and mist in the air, assuming the respirator is fitted properly to your face.

You can buy high efficiency respirators in two basic styles.

The first basic style is the disposable respirator. It will look like a cup of soft white felt or fabric that fits over your mouth and nose.

It must have at least two sturdy, adjustable elastic bands to mold the mask firmly to the face. 3M’s disposable 8233 respirator is N100 or P100 rated and costs under $10 USD. Discard a disposable respirator when it gets dirty or hard to breathe through, whichever comes first. You can buy one here.

The second basic style is a “half face” respirator that comes in two parts — a reusable facepiece and replaceable cartridges. Facepieces come in sizes; many women will want the small facepiece. 3M makes a variety of facepieces that can be fitted with different types of cartridges.

3M’s reusable 6191 facepiece fitted with N100 or P100 cartridges costs under $20. I replace particulate cartridges when they get hard to breathe through or when they look dirty, whichever comes first. You can buy one here.

Now – making century eggs has been a well-documented process for hundreds of years – to make them in large quantities in the traditional method, I quote an early 20th-century recipe:

“To an infusion of 1 pounds of strong black tea are stirred in successively 9 pounds of lime, 43 pounds of common salt, and about 1 bushel of freshly burned [wood] ashes,” they wrote. “This pasty mixture is put away to cool overnight. Next day 1,000 ducks’ eggs of the best quality are cleaned and one by one carefully and evenly covered with the mixture, and stored away for 5 months. Then they are covered further with rice hulls, and so with a coating fully 1/4 inch thick are ready for the market.”

You can read the entire chemical analysis and instructions here.

Through the miracle of modern chemistry, that laborious process can now be cut back from several months to 2 weeks or so and in a far less messy fashion. Instead of using mud to encase the eggs, you can use anything to coat the eggshells so that oxygen can’t get in – some processes use different chemicals, but I use a natural and effective alternative: beeswax! You can buy beeswax pellets here.

It may be a lot easier to buy century eggs at your local Chinese grocer, but since you never know if they’re using toxic chemicals to increase the speed of the process or improve the color (the industry was using lead for years until finally called out), and nothing can match the satisfaction of making your own!

So – go forth, gird your culinary loins and be safe making them, my Citizens!

Battle on – the Generalissimo