Moon cake is a Chinese bakery product traditionally eaten during the mid-autumn festival, locally known as the Zhongqiu festival. A typical moon cake is a round or rectangular pastry made up of lotus seeds and duck egg yolks.
According to a statement from the State Administration for Industry & Commerce (SAIC), food safety inspectors went to inspect all of the 281 units in China to check for unsafe food before the festival, which falls on September 12.
The checks were conducted by inspectors in 20 provinces and municipalities including Guangdong, Beijing and Shanghai, involving a sample of 760 batches of moon cakes.
Under the checks, the SAIC found that 96 per cent of the tested moon cakes sold by China's 281 distribution units were of a standard safe, while 4 per cent of them were contaminated.
The statement reveals that the contaminated moon cakes were most probably a result of poor sterilization and sanitation, which caused them to contain excessive amounts of bacterial colony.
The contaminated moon cakes have since been removed from retail shelves in the country, according to the statement, which further reveals that around 15 tonnes of these moon cakes have been confiscated.
This is the second time in two months that contamination has been associated with these food products, which are ethnically centric to China.
Earlier in August excessive amounts of nitrite were found in edible bird's nests in the province.
At that time the Zhejiang Provincial Administration for Industry and Commerce, the quality regulator for Zhenjiang province said that the tested cubilose (another name for edible bird's nests) was not locally produced, but imported from Malaysia, but it posed a threat to consumers' health in China.
Spot checks on blood-red cubilose, a rare type of edible bird's nests, from 491 dealers in Zhejiang have shown that nitrite levels averaged 4,400 mg per kg, far beyond the allowed cap of 70 mg per kg.