McDonald's was found to have received hygiene warnings from the nation's food safety authorities more frequently than its smaller rivals here, according to a parliamentary report on Wednesday.

Citing data submitted by the Ministry of Food and Safety, Rep. Ko Young-in of the main opposition Democratic Party of Korea said in the report that the US hamburger chain with some 400 outlets nationwide received a total of 91 penalties in the 2018-2022 period.

The data showed that McDonald's had the highest penalty rate per store, followed by Mom's Touch with 1,314 stores that received 189 hygiene-related penalties during the same period.

Next followed KFC, which received 25 penalties across its 188 stores here, and sandwich franchise Subway, with 49 penalties from its 428 stores in Korea.

The report pointed out that out of the hygiene-related penalties McDonald's received, it received the most penalties for "violation of standards" for its food products -- referring to excessive additives to its products and over-the-standard germs found in ingredients.

McDonald's received the second-most penalties for "violation of hygiene," which refers to the state of hygiene found in the storage spaces of ingredients and the cleanliness of each restaurant's kitchen.

"If we translate the data into number of penalties per store, McDonald's penalty rate per store stands at 0.22. The national average hygiene-related penalty rate per store is 0.2," said an official from the Food Ministry.

"McDonald's penalties currently are not far above the national average, but as McDonald's is one of the most popular fast food franchises in the country, it will need to bring down the number of hygiene-related penalties it gets from the Ministry of Food," he added.

The recent data follows a series of controversies surrounding McDonald's hygiene at franchise stores.

On Jan. 25, an online post showing a picture of yarn in a McDonald's McMorning pancake combo stirred controversy.

"I bought two McMorning sets with my son, gave him a hotcake, ate a muffin, and after almost finishing everything, took something out from my mouth to find that I was chewing on a thick piece of thread," the post said.

In November 2022, a half-cut worm was found in a McSpicy Shanghai burger in Gyeonggi Province -- and a similar incident followed a month before that, where a moth caterpillar that was later found to have originated from a lettuce farm was found dead in the same burger. The customer who consumed part of the product was later reportedly hospitalized for a stomachache.

"As fast food restaurants are favorite places for children and senior citizens, it is necessary to more thoroughly comply with legal hygiene standards," said Rep. Ko Young-in.

"Each franchise headquarters should educate individual stores to thoroughly manage hygiene and pay attention to their own inspections."