Brewmaster Toshi Ishii has unleashed his finest real ales on the discerning drinkers at the Great British Beer Festival, the first time that cask-conditioned Japanese beer has been available in the UK -- and they're going down rather well.
Beer drinkers across the globe may have heard of Japanese brewing giants Asahi and Kirin but Ishii, head of the Nagoya-based Yo-Ho Brewing Company, is determined to put his ground-breaking Japanese real ale on the map.
He brought over a barrel each of Yona Yona ("Every Night" in Japanese) Ale and Tokyo Black Ale to the five-day London festival, which boasts the biggest range of beer of any in the world.
The annual event, which closed on Saturday, is the world's largest showcase for real ales -- beer brewed using traditional ingredients and left to mature in the cask from which it is served.
In the Bieres Sans Frontieres section at the rest of the world bar, Ishii tells curious punters all about his Japanese real ale revolution.
"I hope Japan will become a nation of real ale drinkers," Ishii said as he proudly poured a taste of Tokyo Black.
"Many Japanese people are not familiar with the difference between lagers and real ales," he said.
"I want to introduce real ales to Japanese people and I want to introduce our beers to people over here," he added.
Ishii learnt the tricks of the trade at the Stone Brewing Co in San Diego, California, and took the real ale craftsmanship he learnt there back home to begin teaching Japanese brewers.
"We didn't have any breweries in Japan that could make cask ales," he said.
Since he started brewing real ale at Yo-Ho in 2002, there are now 15 breweries in Japan that can make it, along with 250 micro-breweries in Japan, Ishii said.
Yona Yona, a US-style golden pale ale, is Yo-Ho's flagship beer and a bestseller among craft beers in Japan.
Tokyo Black, which is gaining popularity in Japan among Guinness drinkers, is a porter -- a dark, slightly sweetish beer.
Ishii is determined to return to the event next year, and on the evidence of empty glasses and drained casks, British punters will be glad to have him back.