The latest tests found that Chinese liquid dairy products met the new temporary restrictions on melamine, the country's top quality control agency said yesterday.

It was the ninth investigation on the industrial chemical following the tainted baby formula scandal that killed at least three infants and sickened more than 50,000 others, according to the General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ).

The latest tests covered 532 batches of liquid milk, including yogurt, from 69 brands in 23 major cities nationwide, the agency said.

At present, 4,213 batches of liquid dairy products from 131 brands produced after Sept. 14 were tested and all in line with the limit, it added.

Melamine, often used in the manufacturing of plastics, was added to sub-standard or diluted milk to make the protein levels appear higher.

China on Wednesday set temporary limits on melamine content in dairy products. The limits were a maximum of 1 mg of melamine per kg of infant formula and a maximum 2.5 mg per kg for liquid milk, milk powder and food products containing at least 15 percent milk.

The State Council, or Cabinet, issued a series of quality control regulations for dairy products on Thursday.

The regulations tighten control of how milk-yielding animals are bred, how raw milk is purchased and the production and sales of dairy food.

They promised more severe punishment for people who violated safety standards and quality control departments that failed to fulfil their duties.