Anaerobic fermentation, a fairly new form of coffee processing, can truly wow with its bold and memorable flavor profile when well executed from farm to cup.

Bunker Company’s Costa Rica Cordillera de Fuego is one such example.

There is that initial, irresistible funk characteristic of fermented coffee followed by fragrant and rich notes of cinnamon and cacao nibs.

“Usually there are three types of coffee processing -- washed, pulped and natural,” Bunker Company CEO Park Seung-kyu, 33, explained in an email interview.

“However, with the evolution of coffee culture fresh methods of processing are being developed including one of the most buzzed-about methods -- anaerobic fermentation.”

Park explained that anaerobic fermentation involves pulping the coffee and then sealing the beans with their mucilage intact in a stainless steel tank.

The theory behind this process is that limiting the amount of oxygen promotes the production of lactic acid, resulting in an exciting flavor profile. 

Park stressed how the diverse range of chemical reactions that occur during the process requires thorough management and techniques to yield good coffee.

When Bunker Company’s Costa Rica Cordillera de Fuego is extracted with an espresso machine, Park says the flavors of cinnamon will come to the forefront while brewed as pour-over coffee, one can enjoy its wine-like aroma.

“Right now we are using coffee from the de Fuego farm to extract our juicy long blacks and espressos,” Park said.

When Park refers to “our juicy long blacks and espressos,” he means those of Bunker Company, his roaster-cafe, which until last month was solely located in Hanam, Gyeonggi Province.

“We first started in Gwanak-gu Nakseongdae in 2014,” said Park. “In 2018 we moved to Hanam. After we moved to Hanam, many found its distance from Seoul inconvenient and we also needed a showroom.”

After planning a second location for a year, Bunker Company unveiled its Apgujeong location on Oct. 17. Here, one can enjoy both Bunker Company’s brews and beans along with a selection of baked goods.

According to Park, the Hanam store focuses on brews extracted from the espresso machine, while its Apgujeong location also serves coffee extracted from a Marco SP9 -- an automated pour-over coffee brewer.

“The Hanam store’s concept is that of a roastery while the Sinsa-dong store is more a space where we showcase our coffee to consumers,” said Park.

Coffee aficionados may recognize Park as the barista with his own YouTube channel, where he delves into the coffee business as well as the art of brewing and appreciating coffee with a well-mannered demeanor and a perfectly slicked back coif.

Before Park launched his YouTube channel in 2019 and before he started Bunker Company in 2014, Park was first and foremost a barista.

The year was 2009 when Park became a barista. He then found a job at a company that imported specialty coffee and went on to become a Q-grader, using his skills to contact coffee estates around the world and roast coffee.

According to Bunker Company’s official website, Park also won the 2011 Espresso Thrown Down and the 2012 Barista Association of Korea’s Barista Championship.

Among a selection of three blends and six single-origins is Bunker’s #8.5 Buttery blend, which is used for Bunker’s dark long blacks, a potent Americano crafted from two espresso shots and 130 to 150 milliliters of water for the iced and 200 ml for the hot variations.

When served as a hot long black, this blend is intense, slightly bitter with little to no acidity -- the kind of coffee that pairs well with food.

“The main base, 63 percent, features three varieties of coffee from Colombia,” said Park, explaining how he went for a coffee that is slightly acidic with flavors of walnut and a buttery mouth feel.

Park takes great pride in Bunker Company’s blends.

“I prefer coffee with body and sweet flavors, because the flavor that we can best taste is sweetness,” Park elaborated. “Also, the reason I prefer blends to single origin coffee is because I believe that blends can fill any void present in single origin coffee. Anyone can make a complex blend but not everyone can make a blend that exhibits great balance and I find that interesting.” 

Park also puts a great deal of emphasis on the water used to brew coffee because coffee is mostly water. Sodium ion exchange resin water filters are used for Bunker’s espresso machines to extract coffee with “body and a sweet flavor profile.”

The Marco SP9 at Apgujeong uses a filter that enables cafegoers to choose between sweet or acidic pour-over coffee.

Clearly Park takes his coffee seriously, using the motto “make coffee with a bit of swagger” for Bunker Company to remind himself that being a barista means focusing on the basics of coffee and that only by knowing those basics can one showcase one’s skills.