The top quality watchdog reiterated its resolution on Friday to crack down on the illegal use of industrial gelatin in food processing.

"We will carry out a thorough and strict inspection of all producers of edible gelatin and food manufacturers that are using edible gelatin, and we will severely crack down on illegal activities," Fu Wenbiao, deputy director of the general office of the General Administration of Quality Supervision, Inspection and Quarantine, said at a news conference.

Fu's remarks came as the agency recently sent eight supervision teams to 17 provinces and regions to inspect the production and use of edible gelatin in order to ensure the safety of food eaten or sold during the coming three-day Labor Day holiday.

Edible gelatin is a protein substance extracted from healthy animals' skin and bones. It is most often used as a gelling agent in the food and pharmaceutical industries, going into products such as jam and yogurt. Inedible gelatin, in contrast, is extracted from leather or even the skin and bones of sick animals and may be put toward industrial uses.

Dong Jinshi, a food safety expert, said edible gelatin must meet more than 20 standards pertaining to its content of heavy metals and other elements before it can be used in food, while inedible gelatin must only meet five standards before it can be used in other sorts of products.

Inedible gelatin can also brought up to the standards of the edible variety if it is first subjected to certain procedures, he said.

"So the priority in the inspections should be to look at providers of raw materials and then go down to gelatin producers and food manufacturers," Dong said. "The whole industrial chain should be put under strict supervision and any omissions will cause big troubles."