There is a food that has been called "rotten," "weird," and even "gross" by those who have never tasted it. It has been featured on shock-game shows and whispered about in Western kitchens with a mixture of fear and fascination. And yet, in China, Hong Kong, and across Southeast Asia, it is a beloved comfort food — a delicacy that has endured for over five centuries.

This is the century egg. And PRO FUSION's Preserved Soft Yolk Duck Eggs are the premium version of this most iconic preserved egg — a creamy, custard-like yolk that flows slightly when cut, wrapped in a firm, translucent dark jelly with a clean, savory, mineral flavor.

Let's explore the strange and wonderful history of this ancient delicacy, what makes PRO FUSION's soft yolk eggs so special, how they compare to the eggs you know, and how to turn them into a stunning century egg sesame roll that will change the way you think about preserved eggs forever.

A 500-Year-Old Accident That Became a National Treasure

The century egg was not invented. It was discovered.

Legend tells of a farmer in rural China who found a cache of duck eggs lying in a shallow pool of slaked lime — a muddy mixture of quicklime and water. Whether the eggs had been buried by a previous owner or simply abandoned, the farmer decided to try one. To his surprise, the egg had transformed: the white was a dark, translucent jelly, the yolk a creamy, greenish-gray paste, and the flavor was deeply savory, intensely umami, and unlike anything he had ever tasted.

The farmer set out to replicate the process. And in doing so, he created a delicacy that would endure for centuries.

Scientists estimate that the century egg dates back more than 500 years to the Ming Dynasty, most likely originating in Hunan Province. The oldest known records of people making century eggs come from this period, and they are still popular in Hunan today, where they are often served mashed with sautéed chillies, garlic, and sesame oil.

The name "century egg" is a misnomer. The preservation process takes weeks to months, not a hundred years — typically anywhere from seven weeks to five months, depending on the method. In Chinese, the egg is called pí dàn (皮蛋) , which simply translates to "preserved egg" — a far less dramatic name than its English counterpart.

For centuries, century eggs were made by farmers and villagers for their own tables. They began appearing on restaurant menus in Hong Kong in the 1940s, when renowned Chinese chefs fled the mainland during the Chinese Civil War and brought their regional dishes with them. One of Hong Kong's most famous restaurants, Yung Kee, became renowned for its century eggs, typically served as a starter on a thick bed of bright pink ginger.

Today, century eggs are a staple in Chinese supermarkets, congee shops, and home kitchens around the world — a food that is simultaneously feared by outsiders and cherished by those who grew up with it.

The Science of Transformation

What happens inside a century egg is a kind of culinary magic — or, more accurately, a kind of alkaline chemistry.

The traditional method involves coating raw duck eggs in a thick paste of wood ash, calcium oxide (quicklime), sea salt, and black tea, then wrapping them in rice husks and leaving them to cure for several months. The alkaline coating raises the pH inside the egg dramatically — from a normal pH of 7 to 8 up to pH 9 to 12 — creating conditions harsh enough to transform the proteins without any heat.

As the alkali penetrates the shell, it breaks apart the protein molecules in the white and yolk, causing them to unfold, clump together, and cross-link into a gel. In the white, the proteins reorganize into a highly elastic gel — which is why the finished product has that bouncy, jelly-like texture instead of the firm bite of a boiled egg. The yolk undergoes a softer version of the same process, forming a low-hardness gel that ranges from creamy to slightly grainy, depending on how long the egg was cured.

The color changes come from the same chemical reactions. The dark amber-to-black color of the white and the deep green-gray of the yolk are byproducts of protein degradation and the interaction between hydrogen sulfide and minerals in the egg. Those sulfur-containing amino acids also break down during the process, releasing hydrogen sulfide and ammonia — the compounds responsible for the egg's distinctive pungent smell.

The result is a food that looks strange, smells strong, and tastes — to those who love it — deeply, profoundly delicious. The white is mild and mineral, with a firm, gelatinous texture. The yolk is rich, creamy, and intensely savory, with an umami depth that is often compared to a very ripe cheese.

What Makes PRO FUSION's Soft Yolk Century Eggs Special

Not all century eggs are created equal. The standard variety has a hard, fully set yolk — dense, sliceable, and convenient for cold dishes and congee. But PRO FUSION's Soft Yolk (溏心) century eggs are something else entirely.

The yolk is creamy and custard-like, with a soft center that flows slightly when cut — a texture that is prized by connoisseurs as a step above the standard hard yolk variety. The egg white sets into a firm, translucent dark jelly with a clean, savory, mineral flavor. The eggs are made from quality duck eggs using traditional preservation techniques, and each pack contains six individually preserved eggs (360g total), with the origin being China.

PRO FUSION describes these eggs as "the premium version of China's most iconic preserved egg" — and the description is apt. The soft yolk is the hallmark of a carefully made century egg, a sign that the curing process has been precisely controlled to achieve that delicate, custard-like texture rather than a uniformly dense one. The tasting notes are equally precise: the white is firm and glossy with a mild, clean savory flavor, while the soft yolk is dark grey-green, smooth, and creamy — rich with umami depth and a subtle earthiness.

The brand recommends pairing these eggs with acidic, garlicky, or salty condiments that balance and brighten the flavor — a classic approach that speaks to the egg's intensity.

Century Eggs vs. American Eggs: A Different Universe

If your experience with eggs is limited to the sunny-side-up, scrambled, or hard-boiled varieties, the century egg will seem like it comes from another planet. Here's how it compares:

Texture. An American hard-boiled egg has a firm, opaque white and a dry, crumbly yolk. A century egg has a translucent, gelatinous white and a creamy, custard-like yolk — a completely different mouthfeel that is simultaneously bouncy and silky. Where a boiled egg is mild and familiar, a century egg is complex and surprising.

Flavor. A regular egg tastes like — well, egg. A century egg tastes like intense umami, minerals, and a faint whisper of ammonia — a flavor that is often compared to ripe blue cheese or a rich, aged parmesan. It is not a subtle flavor. It is a bold, assertive, deeply savory one that demands attention.

Cultural Perception. In America, the century egg has developed a poor reputation — its dark, alien appearance and strong aroma have made it a staple of shock-game shows and "gross food" challenges. In China, it is a comfort food — something that children grow up eating, that mothers serve when you have a toothache, and that restaurants proudly feature as a delicacy. The same food, two completely different cultural lenses.

Nutritional Profile. Century eggs are nutritionally similar to fresh duck eggs, with a few notable differences. The protein content is actually higher — around 13.1% compared to 9.3 to 11.8% in a fresh duck egg — because moisture slowly leaves during curing, concentrating the nutrients. Fat content drops slightly, and the curing process lowers cholesterol and phospholipid levels in the yolk compared to fresh eggs. Mineral content, on the other hand, increases. One egg contains approximately 60 calories, with a macronutrient breakdown of 19% carbs, 43% fat, and 38% protein, and is a good source of vitamin A (17% of your daily value).

The Takeaway. Where American eggs are mild, familiar, and visually neutral, century eggs are bold, complex, and visually striking. They are not a substitute for a breakfast egg. They are a different category of food entirely — one that rewards the curious and delights the initiated.

A Note on Safety: Lead-Free and Modern Production

Historically, some century egg producers used lead oxide in the curing mixture to speed the process or stabilize the egg white. This practice has raised concerns about lead contamination, and surveys have found elevated lead levels in some century eggs.

However, modern production methods have largely eliminated this risk. Many manufacturers now use lead-free processing methods, and food safety regulations in many countries require that century eggs contain no more than 0.5 milligrams of lead per kilogram. PRO FUSION's eggs are made using traditional preservation techniques, and like all commercially sold century eggs in regulated markets, they are subject to food safety standards. As with any preserved food, it is always wise to read the product label carefully and purchase from reputable sources.

Recipe: Century Egg & Sesame Rolls (皮蛋芝麻卷)

This is a modern, elegant twist on the classic century egg — a delicate sesame roll that wraps the creamy, savory egg in a nutty, slightly sweet sesame coating. It is inspired by the traditional Chinese love of pairing century eggs with sesame oil and toasted sesame seeds, but reimagined as a beautiful, shareable appetizer that will surprise and delight your guests.

The soft, custard-like yolk of PRO FUSION's century eggs is the star here — it provides a rich, creamy contrast to the nutty sesame and the crisp, refreshing cucumber. The roll is simple to make, visually stunning, and surprisingly approachable — even for first-time century egg eaters.

Prep time: 20 minutes | Cook time: 5 minutes (for toasting sesame) | Makes: 8–10 rolls

Ingredients

For the rolls:

• 2 PRO FUSION Soft Yolk Century Eggs

• 1 small cucumber, julienned

• 2 scallions, thinly sliced

• 1 tbsp toasted sesame seeds (plus more for coating)

• 1 sheet nori (optional, for wrapping)

For the sesame coating:

• 3 tbsp toasted white sesame seeds

• 1 tbsp toasted black sesame seeds

• 1/2 tsp sea salt

• 1/4 tsp sugar

For the dipping sauce:

• 2 tbsp light soy sauce

• 1 tbsp black vinegar (Chinkiang vinegar)

• 1 tsp sesame oil

• 1 clove garlic, minced

• 1 tsp chili oil (optional)

Instructions

1. Prepare the sesame coating.
In a small dry skillet, toast the white and black sesame seeds over medium heat for 2–3 minutes, until fragrant and lightly golden. Transfer to a small bowl and mix with the sea salt and sugar. Set aside.

2. Prepare the century eggs.
Peel the PRO FUSION century eggs. The soft yolk is delicate, so handle them gently. Cut each egg into quarters or eighths, depending on how large you want your rolls. Tip: Dip your knife in hot water and wipe it clean between cuts to prevent the creamy yolk from sticking and to get clean, beautiful slices.

3. Build the rolls.
If using nori, cut the sheet into thin strips about 2 inches wide. Lay a strip of nori flat on a clean surface. Place a slice of century egg at one end, top with a few strips of cucumber and a sprinkle of scallions, and roll tightly. If not using nori, simply place the century egg slice on a small piece of cucumber and top with scallions — the cucumber acts as the "wrapper."

4. Coat the rolls.
Gently roll each assembled roll in the sesame coating mixture, pressing lightly so the seeds adhere. The creamy yolk will help the sesame seeds stick. Set the coated rolls on a serving plate.

5. Make the dipping sauce.
In a small bowl, whisk together the light soy sauce, black vinegar, sesame oil, minced garlic, and chili oil (if using). Taste and adjust the seasoning — the sauce should be salty, tangy, and slightly nutty, the perfect counterpoint to the rich, creamy egg.

6. Serve.
Arrange the sesame rolls on a plate and serve immediately with the dipping sauce on the side. The rolls are best enjoyed fresh, while the cucumber is crisp and the sesame coating is fragrant. Serves 2–4 as an appetizer.

Tips:

• For a more substantial roll: Add a thin slice of smoked salmon or prosciutto inside the roll before coating. The saltiness and richness complement the century egg beautifully.

• For a vegetarian version: Omit the nori and use thin strips of blanched cabbage leaf or rice paper as the wrapper.

• Make it a meal: Serve the rolls over a bed of steamed jasmine rice with a drizzle of the dipping sauce for a light, elegant lunch.

Bring Home the Century Egg

PRO FUSION's Preserved Soft Yolk Duck Eggs are more than a curious novelty. They are a direct connection to a 500-year-old culinary tradition — one born from an accidental discovery in a muddy pool of lime, perfected over centuries of Chinese craftsmanship, and now available in a premium, soft-yolk format that showcases the egg at its most creamy, custard-like, and deeply savory. They are rich in umami, higher in protein than fresh eggs, and lower in cholesterol — a food that nourishes as much as it intrigues.

Ready to taste the century? Pick up a pack of PRO FUSION Preserved Soft Yolk Duck Eggs (Century Egg) at MyAsianStore.com and discover the creamy, custard-like magic of China's most iconic preserved egg for yourself.