China's Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) issued a report this week on a random survey carried out on 31 carbonated drinks produced by more than 20 different companies around the country.
It found that most companies passed four of the six criteria tested.
Coca-Cola and Pepsi producers in different provinces passed all of the tests, as well as leading Chinese producer Wahaha, part-owned by Danone.
But among products made by smaller companies, several contained higher levels of sweeteners, colours or preservatives than stated on the label, and three used sweeteners when the label said they contained sugar.
One product contained insoluble solids and two had levels of citric acid above required limits.
One company overused saccharin sodium in its product, said the report on AQSIQ's website.
It congratulated large firms such as Coca-Cola for a 100 per cent pass rate for their products, while those producers who did not meet standards will be asked by local authorities to reformulate the drinks.
Nanning-based Qingfeng and Jinchashan Food and Beverage company, as well as Yunnan-based Senquan Beverage had the lowest scores in the tests.
They will be given a deadline to meet the standards.
AQSIQ says it carries out selective inspections of certain products every year to check up on the safety of food and drinks.
China's carbonated drinks sector was worth US$6.7 billion in 2003, according to Datamonitor, significantly smaller than Japan's US$36 billion sector.
However it is growing by 8 per cent each year compared with only 2 per cent in Japan.