Yoon Ho-jung, executive director of Korea Yakult, has been flying under the radar.

Forbes Korea assumes that Yoon has 592.2 billion won ($578 million) in company stocks, which makes him the 45th-richest stockholder in the country. But his presence has been largely unnoticed both internally and externally.

Yoon has long been seen as living in the shadows of his 87-year-old father, Yoon Deok-byeong, who founded the company as a joint venture with the Japanese beverage company Yakult in 1969.

The producer of Yakult drinks ― 65-milliliter bottles of sugary water mixed with fermented lactobacillus and skimmed milk powder ― eventually became a beverage empire posting 980 billion won in sales in 2013 after adopting door-to-door distribution through “Yakult Ladies” and other marketing strategies.

The company also owns instant noodle maker Paldo; rice beverage maker Birak; Neungyule Education; medical appliance maker Curexo; and dessert cafe franchise Coco Bruni.

Rumors have been mushrooming that the 43-year-old Yoon has been vigorously seeking opportunities to impress his father, who is still an active decision maker.

However, many of the pet projects that are believed to have been launched by the junior Yoon have been less than impressive.

Medical robot manufacturer Curexo posted a 13.4 billion won loss in operating loss last year while Coco Bruni, which opened in 2010 during a dessert and coffee shop boom, marked a loss of 4.6 billion won in 2012.

“The future of Korea Yakult isn’t all rosy either because the fermented dairy market is quite stale,” a market watcher suggested.

Moreover, Yoon Ho-jung faced media and public scrutiny earlier this year when he was revealed to have bagged dividend profit of up to 3.1 billion won from Paldo while the company posted 36.6 billion won in losses. Paldo, a company wholly owned by Yoon Ho-jung, has suffered since it was separated from Korea Yakult’s ramen division following its one-time hit Kkokkomyeon in 2011.

The junior Yoon is expected to tackle yet another problem once he inherits his father’s kingdom. In 2013, a group of Internet users and civic activists boycotted the company’s products because of the elder Yoon’s alleged political bias and “wrong understanding of history.”

According to the May 16 National Awards Foundation, Yoon Deok-byeong donated more than 765 million won to it from 1998 to 2012 ― more than 35 percent of its total donations during this period.

The foundation was established by a group of rightists who honor the May 16, 1961, coup initiated by former President Park Chung-hee, who went on to establish a military junta. The coup was later ruled unconstitutional by the Supreme Court. Yoon served as chief of security for the Park Chung-hee administration.

“It seems clear that Korea Yakult is undermining the history of the Republic of Korea,” the Institute for Research in Collaborationist Activities said.

Korea Yakult explained that the donation was a part of its corporate social responsibility activities, and that the younger Yoon remains unattached to all business affairs.

By Bae Ji-sook (baejisook@heraldcorp.com)