Beijing's ban on adding melamine now applies to all foods, not just dairy products, according to a circular issued on Wednesday.
The State Council also released a notice on strengthening the crackdown on illegal food additives.
Vice-premier Li Keqiang , also the State Council's Food Safety Commission director, chaired a meeting on the issue and vowed to fight all types of food safety problems with a 'firm attitude and tough measures', state broadcaster China Central Television reported.
Baby foods will be allowed to contain up to 1mg of melamine per kilogram, and for foods aimed at elderly consumers, the melamine level is capped as 2.5mg per kilogram, according to the circular from three ministries - health, industry and information technology, and agriculture - the State Administration for Industry and Commerce, and the General Administration of Quality Supervision, Inspection and Quarantine.
Beijing has been more sensitive to food additive issues since Sanlu-brand baby formula tainted by melamine killed at least six babies and caused 300,000 infants to develop kidney stones in 2008. However, food scandals show little sign of abating.
The new restriction supersedes the 2008 dairy product regulation, which had set the highest volume of melamine in baby formula as 1mg per kilogram and 2.5mg for each kilogram of other milk-related products.
Wu Yongning, a nutrition and food safety researcher at the Chinese Centre for Disease Control and Prevention, was quoted by The Beijing News as saying the new melamine content standard was in line with the one stipulated by the Codex Alimentarius Commission, which is part of the United Nations' Food and Agriculture Organisation and the World Health Organisation.
The reason adding melamine - a chemical used in plastics that can make the protein content of milk appear higher - is banned is that it is considered neither a food raw material nor an acceptable food additive, according to the circular. It is toxic and will hurt reproduction and urinary organs if consumed over the long term, medical experts say.
However, the ban does make allowance for its existence naturally or in minute amounts in packaging.
'Melamine, as a chemical material, can be applied in the manufacturing of plastic, painting, adhesive and food packages,' the circular states. 'Literature shows that melamine could be absorbed by food products from the environment, packages or other means, although remaining at low level.'
Professor Li Jianrong of Zhejiang Gongshang University said the ban was a positive step. 'A stricter standard is good for the industry and demonstrates the central authorities' determination,' he said. 'Melamine-tainted milk has brought huge damage to our society.'
Professor Wang Shiping, of the China Agricultural University, said the 2008 regulation had always been a transitional measure until a tougher standard could be brought in.
'Without it, there would have been panic about melamine in other kinds of food apart from milk.'