China launched the campaign in April following a spate of tainted food scandals — included pork found on the market so loaded with bacteria that it reportedly glowed in the dark.
Nearly six million food businesses have now been investigated and more than 4,900 shut down for “illegal practices”, the government’s Food Safety Commission said in a statement.
Police have also destroyed “underground” food production and storage sites, and arrested around 2,000 suspects, it said, adding that anyone found breaking the law would be severely punished.
China pledged to clean up its food industry after milk products tainted with the industrial chemical melamine — added to give the appearance of high protein content — killed at least six babies and sickened 300,000 in 2008.
In 2009 the country passed a food safety law to try to allay public concern.
But authorities have continued to discover bean sprouts laced with cancer-causing nitrates, steamed buns with banned chemical preservatives, and rice laced with heavy metals, prompting the latest crackdown.