China's top quality regulator on Sept 7 reported six kinds of substandard mooncakes following examinations on nearly 300 different products just days before annual Mid-Autumn Festival begins.

High bacterial content was found in mooncakes produced by several companies, including Lanzhou Tianshengyuan and Changchun Jiangbo Food Company, the regulator said.

The General Administration of Quality Supervision, Inspection and Quarantine said that a total of 13 state-level food-testing organizations had checked 299 kinds of mooncakes produced by 289 companies in 15 provinces, autonomous regions and municipalities in recent weeks.

Test results show that 293 kinds of mooncakes met established quality standards. The mooncakes were examined according to quality indicators such as chemical composition, hygiene standards, food additives, packaging, ingredients and bacterial counts, the watchdog said.

It also required local bureaus to take necessary measures to solve the problems and ordered the companies involved to correct their mistakes.

Meanwhile, the companies will receive follow-up examinations.

Mooncakes are Chinese delicacies traditionally eaten during the Mid-Autumn Festival when families and friends gather together to light lanterns, eat mooncakes and appreciate the full moon.

According to the Chinese lunar calendar, the 15th day of the 8th month is the exact middle of autumn and, on this night, the moon appears at its roundest and largest.

This year's Mid-Autumn Festival falls on Sept 12.