The production of double-yolk eggs by poultry is often related to the abundance of food and the health of the poultry. Double yolk eggs contain two yolks and are very nutritious and are very popular among the public. Nowadays, people have begun to artificially cultivate double yolk eggs, and there are manufacturers that specialize in selling double yolk eggs.

However, some people believe that double-yolk eggs are produced by female chickens due to endocrine disorders and other physiological reasons. It is best not to eat too many eggs. However, natural double-yolk eggs are still rare. Gaoyou Double Yellow Duck Eggs More than 900 years ago, Qin Shaoyou, a famous poet in the Northern Song Dynasty, used duck eggs as a gift to his mentor Su Dongpo, who was then Taichan in Xuzhou. More than 300 years ago, the great writer Yuan Mei visited Gaoyou and tasted Gaoyou duck eggs. He was very impressed. He left a record in the "pickled eggs" section of his "Suiyuan Food List·Small Menu": "Gaoyou is the best pickled egg." , thin in color and rich in oil, Gao Wenduangong likes to eat it first, and put it on the plate to serve the guests. It is always better to cut the shell and use it both yellow and white; do not keep the yellow and remove the white, as the flavor will be incomplete and the oil will disappear. "The Gaoyou duck egg processing factory also started early. In the 31st year of the reign of Emperor Guangxu of the Qing Dynasty (1905), Gaoyou's first egg product company, Yuyuan Egg Factory, came into being. In 1909, Gaoyou double-yellow duck eggs participated in the Nanyang Entrepreneurship Association's Chen Competition and won the reputation of an international famous product. The following year, they were exported to more than 10 countries and regions including the United States, Japan, Singapore, and Malaysia. Gaoyou ducks lay many eggs, with large egg heads and a large yolk ratio. The duck is famous both at home and abroad for its ability to produce double-yolk eggs. The quality of its eggs can be summarized as "fresh, fine, and tender" for the egg white and "red, sandy, and oily" for the yolk. Wang Zengqi once described it in "Hometown Food": "There was a time when it was difficult to find water in the sea, and I really looked down on salted duck eggs from other places." ""The characteristics of Gaoyou salted eggs are that they are fine in texture and rich in oil. The protein is not as dry and powdery as other places, and it tastes like chewing lime. It is usually eaten with more oil than other places. "Use chopsticks to dig in and eat. As soon as the head of the chopstick is pierced, red oil will come out. "River branches, lakes and beaches are ubiquitous high-quality water resources, which are the natural breeding grounds for Gaoyou ducks. Various small animals floating on the surface and living underwater provide the most delicious "live food" for Gaoyou ducks. This has also provided unique natural conditions for the development of ecological duck farming and the development of green products in recent years. In recent years, a number of high-quality brands that have obtained well-known and famous trademarks and green food labels have been developed, such as Red Sun, Sanhu, and Qinyou. Gaoyou people not only cultivate Gaoyou ducks and double-yolked eggs, which are world-class products, but also create a rich duck culture. In the 1950s, Gaoyou folk singer Xia Guozhen's Gaoyou folk song "Counting Duck Eggs" shocked Kyoto with its humorous, brisk melody and rich local flavor, and was praised by Premier Zhou Enlai. Gaoyou Duck is the business card of Gaoyou people. "If you don't know Gaoyou people, you can predict Gaoyou eggs."

As the image ambassadors of Gaoyou, Gaoyou duck and double-yolked eggs have been famous local products that have been presented as tribute to the court and as gifts to relatives and friends since ancient times