Eating cold food on Tomb Sweeping Day(Qingming Festival)？

Tomb Sweeping Day, also known as Qingming Festival, is a traditional Chinese holiday that falls on April 4th or 5th each year. It is a time for Chinese people to pay their respects to their ancestors and departed loved ones by visiting and cleaning their gravesites.

One of the most important customs of Tomb Sweeping Day is tomb sweeping, where families visit the gravesites of their ancestors and clean them by removing any debris or overgrown vegetation. It is also common for people to leave offerings of food, flowers, and incense at the gravesites as a sign of respect and remembrance.

The origins of Tomb Sweeping Day date back over 2,500 years to the Zhou Dynasty. There is a day called Hanshi (寒食节 hán shí jié), which literally means "Cold Food Festival" and was observed on the day before Qingming. During the Han Dynasty, the holiday was combined with Qingming and renamed as Tomb Sweeping Day.

Regarding the origin of the Cold Food Festival, there is a story:

During the Spring and Autumn period, Prince Chong'er of the Jin state was a fugitive and endured a harsh life. Luckily, his loyal follower Jie Zitui was willing to cut a piece of meat from his own leg to provide sustenance for him. Later, Chong'er returned to his state and became an active leader, but Jie Zitui refused to accept any reward or position. Instead, he retreated with his mother to the mountains and refused to come out. Despite attempts to force him out, including setting fire to the mountain, Jie Zitui and his mother perished rather than leave their seclusion. In honor of Jie Zitui's loyalty and sacrifice, Duke Wen ordered the mountain to be named "Continuing Mountain" and a temple to be built in his honor. He also decreed that on the day of Jie Zitui's death, known as the Cold Food Festival, no fires should be lit and people should only eat cold food. With time, the Cold Food Festival merged with the Qing Ming Festival, which became a day for sweeping tombs and honoring ancestors. 

The most representative food of Tomb Sweeping Day is "qingtuan". People start making qingtuan before Tomb Sweeping Day, especially in the southern part of China.

Many poets have written excellent poems for this festival, among which Tang Dynasty great poet Du Mu's " In Qingming" is the most representative：