Qianxihe Food Group said the pork from its pigs, which will be raised in secret locations, would not cause Olympic athletes to fail doping tests due to residual antibiotics and steroids.

"Anti-doping concerns during the Olympics have caused officials to tighten food safety regulations so that athletes will be guaranteed food quality," company spokesman Niu Shengnan said.

The use of antibiotics and growth stimulants to boost yields in meat and vegetables is widespread in China, where unscrupulous food suppliers and patchy quality enforcement have led to a rash of health scares in recent years.

In an indication of the concern Olympic organisers had about food quality, Niu said visitors to the three pig-rearing centres near Beijing had to pass a three-day quarantine process before getting in.

"No living organisms are allowed within 500 metres of the centre ... Even when inspectors go, they must first be quarantined for three days before being allowed to set foot inside," Niu said.

About 50 percent of world's pork is eaten in China, where it is the staple meat. The Chinese character for "home" is made up of the pictograms of a pig under a roof.

DISEASE

Pork prices have rocketed following an outbreak of a variation of Porcine Reproductive and Respiratory Syndrome virus -- also known as blue ear disease -- which has killed about 1 million pigs since May last year.

"We have already begun raising pigs for the Games, so supplies should not be a problem," said Niu.

But supplies of pork from animals that have died of disease are still finding their way onto the open market, the State Administration for Industry and Commerce said on its Web site (www.saic.gov.cn), warning it would crack down.

China's latest gestures in its battle to win public confidence in food supplies came as officials promised a nationwide crackdown on what they said was a serious problem.

A range of Chinese exports, from fish and toys to pet food and toothpaste, has been found to be mislabelled, unsafe or dangerously contaminated, creating an international backlash.

The cabinet, or State Council, had decided to "launch a quality-improvement campaign focused on food safety", said Zhou Baihua, director of the General Administration for Industry and Commerce, according to the government Web site (www.gov.cn).

"The overall quality of our country's products has been steadily improving, but the situation, especially for food safety, doesn't allow for optimism," Zhou said, promising a public relations campaign to accompany the crackdown.

This week marks the start of the one-year countdown to the 2008 Olympic Games. Food for athletes would be strictly monitored through every step of farming, processing and transport, Wang Wei, secretary-general of the Beijing organising committee for the games, told a news conference.

"Our country and the Beijing municipal government are taking the food safety issue very seriously, especially for the Olympics," Wang said.