Salt-Cured, Soy-Marinated, and Fertilized: A Guide to Asia's Amazing Eggs


In 2009 an estimated 63 million metric tons of chicken eggs were produced around the world. A third of them came from China. Though the Western world has a well documented love affair with nature's perfect food, Asia has an obsession all its own, with an unmatched variety of cured, aged, stained, and even fertilized eggs sold right along side fresh eggs. Here's a look at what you'll find beneath their shells.

Salted Eggs

Thumbnail image for 20140508-asian-eggs-salted.jpg

Salted eggs are made by soaking duck or chicken eggs in brine or coating them with a thick salted charcoal paste. Crack through its mildly pungent aroma and you'll find a hazy, runny white and a blazingly orange yolk set into a granular custard. When cooked hard, the sweet and salty yolk imparts a rich, eggy flavor and sandy texture to other food.

How they're used: Salted eggs are most commonly eaten hardboiled as a condiment to congee, or used raw in savory sauces. The yolk alone is often crumbled or shaved over meats or tofu, stir-fried with vegetable greens, or mashed and whisked into creamy sauces or dressings.

Stir fried prawns with salted egg sauce.

In Southeast Asia they're a prized component in special dishes like Sri Lankan mud crab, which is drenched in salted egg cream sauce, or prawns stir fried with salted egg yolks for a rich, distinctly grainy egg undertone. In China and Singapore, salted egg yolks are baked into pastries and cooked into bak chang—bamboo leaf-wrapped triangles of dense glutinous rice formed around a core of pork, salted egg, and spices, And during Chinese Lunar New Year, salted egg mooncakes are common gifts, with the dense orange yolk representing the moon.

Where to find them: You can explore the unique flavor and texture of salted eggs at dim sum joints and in more traditional Chinese restaurants, where the yolk is grated finely over vegetables and meat, imparting a melt-in-your-mouth whisper of unparalleled rich egginess. If you want to try cooking with them yourself, keep an eye out for pre-cooked versions at well-stocked Chinese groceries and in online stores like eFoodDepot and Metzer Farms.

Century Eggs

Cut century eggs in the foreground.

One of the most famous—and most misunderstood—Asian preparations of egg, often found coated in mud and rice hulls and resting in baskets at Chinese markets. Also known as preserved egg, hundred-year egg, or thousand-year egg, it's a duck, chicken, or quail egg preserved in a mixture of clay, ash, salt and quicklime.

Despite the name(s), century eggs haven't been sitting in the bottom of a hole for years. The typical curing time is a few weeks or months, though they are certainly built to last. The mineral-ammonia odor of a cracked century egg earned it the name kai yeow maa in Thai, literally "horse urine egg." But the aroma is just the result of clay and salt curing.

The eggs need no adornment and keep well, making them popular with Chinese migrants as far back in history as the Ming dynasty.

But what do they taste like? Once cracked, the typically grayish speckled shell reveals a dark brown, translucent albumen that is rubbery in texture, with a hint of ammonia. The greenish/grey yolk packs a sulfuric punch and looks muddy and wet with a thick, creamy consistency—not a texture typically fancied by Westerners. But those who aren't put off by looks and smell are rewarded with a mild, gel-textured egg that bears only a faint taste of its mineral odor.

How they're used: One Cantonese treat consists of skewered century egg wedges with slices of pickled ginger. In Shanghai they are mixed with tofu, chili, spring onion, and a generous dousing of soy sauce. In Singapore you can find them adorning congee or pultry.

Where to find them: To try century eggs in the privacy of your own home, pick them up at well-stocked Sino-centric markets. They're usually pre-cooked and packed in Styrofoam boxes as dry goods.

Tea Eggs

Tea eggs are the closest thing you'll find in Asia to Easter eggs. Also known as tea-smoked or marble eggs, they're a hard-boiled eggs "decorated" with marble-like patterns on the surface of the white beneath the shell. They're the result of a cracked hard cooked egg simmered in a concoction of tea and warm spices like anise and cassia. The rich liquid adds a subtle spiced flavor to an otherwise ordinary egg.

Tea eggs in their cooking liquid on the street. Robyn Lee

How they're used: Tea eggs are a common street food in China and Taiwan, often dabbed with a little sesame salt for extra flavor. They're found throughout Southeast Asia as accompaniments to a variety of soups, congee, salads, and savory platters of steamed poultry and roasted meats.

Where to find them: Tea eggs are common in Chinese restaurants and dim sum push carts but harder to find in stores. Still, some Asian markets do carry them if you ask around.

Soy-Marinated Eggs

J. Kenji Lopez-Alt

It's the appearance that often turns Westerners away from these simple eggs, but don't let appearances deceive. A soy egg is as innocuous as a peeled hard boiled egg marinated in soy sauce until the surface takes on a tawny brown color with a midly salty-sweet flavor.

How they're used: Soy eggs are often used as condiments in Chinese dishes, including the ever-popular congee, or cut into wedges and circled around the edge of a platter of food. They're also a common topping for ramen.

Where to find them: They are sometimes found among regular eggs in Asian markets, but if you can't find them we have a recipe right here.


The uncontested "dark lord" of the Western-feared ovum world, Balut is a fully-fertilized duck embryo that is boiled in the shell and eaten. They are an inexpensive, high protein, and a signature snack of the Philippines, but also eaten in Vietnam, Cambodia, and Laos. The maturity of the embryo when cooked is a matter of gustatory preference. Young undeveloped egg—known as penoy in the Philippines—are much like a standard, fertile hard-boiled egg, but with a lumpy texture and a firm little protein blast in the center.

For many Filipinos, the ideal balut is a 17-day-old egg, containing some runny albumen, the yolk, and a miniature fetus. The chick is intact but with undeveloped bones, beak, feathers, and claws. Vietnamese eaters might prefer their balut at about 20 days, just eight days shy of full gestation, with a whole baby duck inside, complete with firm but tender bones and small feathers.

How they're used: Though they're sometimes sautéed or cooked into dishes, balut at any age are most commonly enjoyed sucked right from the shell with a dash of salt or chili and a squirt of lime or vinegar. Slurp out the liquid and eat the solid contents in one continuous move to look like a pro.

Where to find them: Few Asian grocers carry ultra-perishable balut, but some reliable farmsoffer them online, such as eFowl and Metzer Farms, who will rush them to you raw so you can cook them at home.

Tokneneng and Kwek Kwek

These are essentially deep fried hard boiled eggs, common street food in the Philippines. The egg is boiled, cooled, and peeled, then coated in a reddish batter of flour, water and ground annatto seed and fried until golden. Half protein delivery system, half french fry, these eggs are similar in most ways except for the kind of egg itself: tokneneng is made with chicken eggs; kwek kwek with quail.

How they're used: Both kwek kwek and tokneneng are classic Pinoy snacks readily available on the street in the Philippines. They're usually served in a paper bag with a vinegar-based dipping sauce of diced onion, a squirt of lime, and sometimes brown sugar. Dip and pop a kwek kwek and chomp the crispy golden batter "shell" in one bite. Two or three bites finishes the larger tokneneng.

Where to find them: It's hard to find these crispy little egg gems outside of the Pinoy archipelago. But recipes exist online, or if you live near a Filipino community, try to keep abreast of National Day on June 12th, when some expats celebrate in community gatherings with the eggs.