About 80 percent of survey respondents said they are upset about the food safety situation in China, according to a poll released on Thursday, amid media exposure of expired meat supplied to several international fast-food giants in the country.

Nearly 60 percent of respondents said the stage of production and processing bears the highest potential food safety risk, while a quarter of those polled thought it is the stage of raising plants and breeding livestock.

The results are part of a survey conducted by the Beijing research company Horizon Research and Horizonkey, which polled more than 3,166 residents aged 18 to 60 in 20 cities including the four first-tier cities — Beijing, Shanghai, Guangzhou and Shenzhen.

Although most respondents said China's food safety is worrying, more than half believe the situation is improving, according to the survey. More inhabitants from first-tier cities than their counterparts from second-tier cities feel that way, it said.

The poll also showed that the higher the education respondents have received, the more enthusiastic they are about buying imported food. Some 63 percent of those who studied at university level have purchased imported food and about one-third of those think imported food is safer than domestic. Only 45 percent of those who only received primary education have bought imported food and less than 17 percent of them have higher faith in imported food.

Most respondents still trust domestic food despite foreign brands having won a considerable market share in the country, the poll revealed.

In the ranking of the top 10 countries that produce safe food, China ranked second, only coming behind the United States, the research company said.