Shanghai police have detained five people in a probe into a company that allegedly supplied expired meat to fast food chains including McDonald's and KFC.

The five people from the company include a quality manager, according to a statement from the Shanghai public security bureau on Wednesday.

The Shanghai Husi Food Co,  a unit of US-based OSI Group, produced 5,108 crates of meat products, including McNuggets, pork patties and beef steaks using expired or moldy materials, according to the bureau and Shanghai's Food and Drug Administration, which are jointly investigating the case.

The products were sold to brands including McDonald's, KFC, Pizza Hut, Burger King, 7-Eleven and Dicos, according to investigators.

About 100 tons of the Husi products have been sealed up, said Xu Wei, a spokesman for the Shanghai municipal government.

Shanghai-based Dragon TV aired a news program on Sunday claiming that Shanghai Husi had supplied products tainted with reprocessed expired meat to a string of fast food chains and restaurants across China.

Zhang Hui, manager of Husi's quality department, confessed during investigations that the company has been conducting the malpractice for years under tacit approval of senior managers.

Illinois-based OSI has said it was "appalled" and was investigating the matter after a Chinese TV report on Sunday showed staff at its Shanghai Husi facility using expired meat and picking up meat from the floor to add to the mix.

In Japan, a spokesman for Seven & I Holdings Co said a licensee in Shanghai had been selling two hamburger products using meat supplied by Shanghai Husi. Both products were removed from outlets on Monday.

A spokeswoman for FamilyMart Co said the Japanese convenience store chain had begun a supply deal with Shanghai Husi this month, selling a "Garlic Nugget" product at its around 10,000 stores in Japan. Another product, "Popcorn Chicken" began test-sales mainly in Tokyo this week. Sales of both products were halted on Tuesday. The company said there were no reports of any customers falling sick from the products.

"I am deeply sorry for causing this trouble and worry to all those involved," FamilyMart President Isamu Nakayama said. "We do not think there is any problem with our operating structure but the very fact that this happened means that I think that additional checks should be put into place to help reassure consumers."