THE city’s renowned Wangjiasha eatery has stopped selling its signature glutinous treat shaomai after mildew was spotted on the product.

The Wangjiasha store on the Nanjing Road W. has also started an investigation to its shaomai production procedures, according to the market watchdog of Jing’an District.

It remains unclear when the flagship store will resell shaomai, but it is still available in other outlets across Shanghai.

The matter came to light on Wednesday when a customer surnamed Yan complained on Weibo, that two boxes of shaomai bought on Tuesday were moldy.

Yan said his wife discovered the faulty product when they planned to have the shaomai on Wednesday morning. He said it was stored properly in their fridge and he suspected the store had changed the printed date on the package to disguise the fact that the product had expired.

The district’s market watchdog inspected the store after being alerted about the mildew.

Investigation showed the store’s fridge had broken down for a while on Tuesday, which might have caused the problem.

Wangjiasha has refunded Yan 24 yuan (US$3.60).

Meanwhile, mooncakes sold across the city are safe, according to the city’s food and drug administration.

Inspectors tested 200 batches of mooncakes, including popular products made by local renowned brands like Xinghualou and Laodafang.

All the products tested were found to be safe and of good quality.