Sweet buns and dumplings were pulled from the shelves in Hong Kong as authorities checked Monday whether they contained the recycled Taiwanese cooking oil that has sparked a growing regional food safety scare.

An investigation was launched after the oil from a Taiwanese company accused of using illegally recycled products -- including fat collected from cookers, fryers and grease traps -- was exported to the southern Chinese city.

However of 46 samples taken for tests, no tainted ingredients had been detected, a statement published on the Hong Kong government website late Monday said.

Taiwanese authorities say a factory in the south of the island illegally used 243 tonnes of tainted products, often referred to as "gutter oil", to mix with lard oil in a case that has reignited regional concerns about food safety.

The lard oil -- a clear oil pressed from pig fat -- was supplied to at least 900 restaurants and bakeries in Taiwan. The owner of the factory was arrested Sunday.

Hong Kong's Centre for Food Safety is also conducting tests on mooncakes -- pastries that are consumed in vast numbers during the Mid-Autumn festival now being celebrated across China -- from retailers across the city.

Popular bakery chain Maxim's Cakes removed pineapple buns from their shelves over the weekend after confirming they had used oil from Chang Guann, the Taiwanese oil manufacturer at the heart of the scandal.

The chain said there was no evidence the lard oil used to make the buns contained tainted products, but it was removing them anyway "to be ultra cautious on food safety". It has since switched to a Dutch supplier.

Dumpling eatery chain Bafang Yunji also pulled its curry dumplings, local broadcaster RTHK reported, while supermarket Wellcome removed two products.

In Macau, the city's Food Safety Centre said 21 bakeries and food manufacturers had bought oil from Chang Guann through a local importer.

Chang Guann has apologised for the scandal but said it was unaware the oils were recycled.

It is the second food safety scare to hit Hong Kong this summer.

In July McDonald's suspended sales of chicken nuggets and several other items after admitting it imported food from a US-owned firm in China at the centre of an expired meat scandal.

Those living in Hong Kong said they were increasingly concerned about the safety of food, especially imported products.

"It's definitely a problem as it could be really bad for your health," Simon Cheung told AFP as he shopped in the city.