He added that food safety issues in the Chinese supply chain, from chicken to fodder, are widespread.
"No single company can preserve its reputation in such an industrial chain," he said.
An increasing number of fast-food consumers have started to go to other Western chains such as McDonald's or Burger King, he said.
Zhao Ping, a researcher at the Academy of International Trade and Economic Cooperation, said that due to their rising income levels, an increasing number of Chinese people are paying more attention to healthy eating, bringing new perceptions toward foreign fast-food brands and reducing their trust and appreciation of those chains.
David Novak, Yum! Brands' chairman and CEO, said in November that the company was on track to deliver at least 13 percent growth in 2012.
He said that 2013 would be another strong year for the company's China division, given the record development of at least 800 new outlets.
The company operates more than 5,000 restaurants in more than 800 cities in China, and plans to open hundreds more.
Among the existing restaurants, 4,000 are KFC stores, and around 750 are Pizza Hut restaurants.
Foreign quick-service brands have stepped up their development plans in China.
In May 2012, McDonald's said it had increased investment in the country by 50 percent and had opened 225 to 250 new restaurants. McDonald's has 1,400 restaurants so far in China and will exceed 2,000 by the end of 2013.
wangzhuoqiong@chinadaily.com.cn
Spring Festival draws near, immigrant workers have begun to go home, leading a travel peak at the railway station.