Prosecutors in South Korea have asked a court to sentence the owner of a Michelin-starred restaurant to one year in prison for serving a dessert topped with ants, an insect not approved for consumption under local food safety law.

The request, made on Monday, also sought a 20m won (£10,108) fine for the company that runs the restaurant, Yonhap news agency reported.

The restaurant’s owner and the company were indicted on charges of violating the country’s food sanitation act. The ministry of food and drug safety launched its investigation after spotting mentions of the ant dishes in blog posts and social media, rather than through a routine inspection.

The restaurant, which holds two Michelin stars and is located in Seoul’s upmarket district of Gangnam, is reported to have served a sorbet dessert sprinkled with ants for customers who wanted the flavour.

Under South Korean law, only 10 insect species, including grasshoppers, mealworms and silkworm pupae, are approved for use as food ingredients. Ants are not among them.

Businesses wishing to use an unapproved insect must first obtain temporary approval, a process the restaurant did not follow, the ministry said. Violating the law carries a maximum penalty of five years in prison or a 50m won fine.

Prosecutors allege the restaurant imported dried ants from the United States and Thailand from 2021 and served them on dishes for around four years, selling the ant-topped dessert roughly 12,200 times for total revenue of about 120m won (£60,647). Prosecutors estimated about 49,000 ants were used in total.

The restaurant’s defence disputed that figure in court, arguing that only about 60% of customers accepted the ant topping when offered, meaning the prosecution’s estimate, based on all customers, was too high.

They also noted that only a small number of dishes on the restaurant’s 15-course menu included ants, and that restaurants in countries including Denmark, the UK and Australia use ants as an ingredient.

It was reportedly explained to prosecutors that the restaurant’s chef had used ants to add acidity to dishes while working in the US and Europe, and had not realised doing so was illegal in South Korea.

Sentencing is scheduled for 2 September.