Last Friday was the Lantern Festival, one of the most important Chinese festivals, and the traditional food for that day is tangyuan, or dumplings made of glutinous rice flour and sweet fillings.

Ningbo city in Zhejiang province is believed to be the place where the famous snack was invented, but even in Ningbo, most tangyuan sold in supermarkets are not local products.

Although many producers, including some market leaders across the nation claim their products are "Ningbo tangyuan" or "Ningbo-flavor tangyuan", very few of them are actually based in the city, said executives from an association representing Ningbo tangyuan manufacturers.