It is said that Tangyuan originated in the Song Dynasty. At that time, a novel food emerged in Mingzhou [now Ningbo City, Zhejiang Province], which was made from black sesame seeds, lard, and white sugar. First, the black sesame seeds were ground into a powder. Then, the lard and white sugar were successively added to the mixture and kneaded into a ball to form the filling. The outside was then rolled into a round shape with glutinous rice flour. After being cooked, it was sweet, delicious, and quite interesting. Because these glutinous rice balls float and sink in the pot, they were originally called "Fúyuánzǐ" (Floating Sons). Later, some regions changed the name to "Yuánxiāo" (Yuanxiao). Unlike people in the north, Ningbo people have the traditional custom of gathering with their families to eat Tangyuan on the morning of the Spring Festival. It is said that Yuanxiao symbolizes family reunion, and eating Yuanxiao signifies family happiness and all the best in the new year.
Eating Tangyuan is also a traditional custom of the Han people, especially prevalent in the Jiangnan region. "Ningbo Tangyuan" is an essential food, a round dessert made from glutinous rice flour. "Yuan" (round) signifies "reunion" and "perfection." Eating Tangyuan during festivals symbolizes family harmony and good fortune, hence it is also called "Fúyuánzǐ". There is a folk saying, "Eating Tangyuan makes you one year older." An ancient poem goes: "In Ningbo, every household pounds rice to make Tangyuan, content and happy for another day."
Yuanxiao is a food that Chinese people traditionally cook and eat on the Lantern Festival, which falls on the 15th day of the first lunar month, and during the Spring Festival. It has had many names, such as "Mianjian" (Noodle Cocoon), "Fenguo" (Powder Fruit), "Yuanbao" (Ingot), "Tangbing" (Soup Cake), and "Yuanbu-luojiao" (Round Not Corners). It was officially named "Yuanxiao" during the Yongle era of the Ming Dynasty.
According to the records of "Zhongzhi Zhi · Shi Shi Hao Shang Ji Lue" by Liu Ruoyu of the Ming Dynasty, Yuanxiao "is made with fine glutinous rice flour, filled with walnut kernels and brown sugar as the fruit filling, and rolled with water into balls the size of walnuts, which is what is called Tangyuan in Jiangnan." Therefore, from this account, Chinese Yuanxiao and Tangyuan are essentially very similar, to the point that Liu considered them the same thing. In reality, however, there are still considerable differences between the two.