For more than 30 years in his profession as a chef of Cantonese cuisine, Wong Kai-kui, 50, has adhered to a "rooted doctrine" that pork soup is the essence, adding flavor to most Canton dishes.

He uses pig bones to stew his soup stock to cook with abalone and sea cucumber. He roasts pork and wraps pig meat in thin pastries to steam for dim sum.

Yet, the kind of meat and even the name of the animal have become a taboo, not to mention using pork as an ingredient, since he started afresh four years ago in the Ningxia Hui autonomous region, inhabited by the Muslim Hui ethnic group.