The convention of eating such eggs, called tong zi dan (童子蛋) in Chinese, literally Boy Egg, is so deeply entrenched that the city of Dongyong listed it as local intangible cultural heritage in 2008.
Boy egg vendors go to local elementary schools to collect urine from prepubertal boys, preferrably under the age of 10, with buckets.
School boys are programmed to the collection mechanism. When nature calls, they go out of the classroom and urinate into a plastic bucket placed on the aisle. Teachers at most schools acquiesced to such behavior. They even remind kids from time to time to avoid peeing inside if they have got a fever. Kids heed what teachers say.
Ms. Li introduced her tip of boiling eggs in boys’urine: first, soak eggs in urine and heat them over the stove. After it boils, get all eggs out and crack their shells before putting them back. After a while, pour in new urine. Repeat it and simmer eggs for an entire day.
Many customers came to Ms.Li’s for the eggs. “It is so yummy. I can eat 10 within a day,” Ms Liu came to Dongyang with her husband several years ago. “I’d never tried it before. After my first taste of it, I’ve become addicted to it,” she said.
In the eyes of many Dongyang people, eggs boiled in boys’urine is a must-have nourishment in spring. Vendors will always tell you, after eating it, you won’t feel sleepy during spring or get a heat stroke during summer.
Wu Yunhua (吴允华), a doctor practicing Chinese medicine, said that, the food has a time-honored history. When living standards were much poorer before, egg was the only nutritious food for peasants, who labored on farms. Urine crystalizes after standing for a while. The crystal is similar in terms of efficacy to a kind of Chinese medicine called renzhongbai. It can treat yin deficiency, decrease internal body heat, promote blood circulation and remove blood stasis. However, she stressed that not everyone is suitable for consuming it. It depends on the individual body nature.
However, Huang Jian (黄坚), director of Department of Nephrology at Central Hospital in the city of Jinhua, said that urine is waste expelled from human body and basically contains no substance conducive to human health. Therefore, he discourages people from eating those eggs.
Jia Suqing (贾素庆), a doctor at Chinese Medicine Hospital in the city of Jinhua, said that in ancient times, prepubertal boys’ urine was often used as an ingredient to enhance efficacy of medication. But from modern-day point of view, it is rather unsanitary. “However, it has become a local custom. I don’t encourage or object to it,” he said.