Kumamoto Prefecture Sake Institute - Sake Online

About Kumamoto Prefecture

Kumamoto Prefecture is located in the central part of Kyushu, facing the Ariake Sea to the west and surrounded by mountains, including the iconic Mount Aso, one of the world’s largest active volcanoes. Its name, meaning "bear origin," reflects the region’s deep connection to nature and rugged landscapes. The prefecture is rich in natural beauty, from the volcanic plains of Aso to the coastal Amakusa islands.

Kumamoto is famous for its local delicacies, including basashi (horse sashimi), karashi renkon (lotus root stuffed with spicy mustard), and Kumamoto ramen, known for its rich, garlic-infused tonkotsu broth. The region also boasts high-quality water sources, making it ideal for sake production. The pure underground water of Aso contributes to the smooth and clean flavors of Kumamoto’s sake, with breweries crafting distinctive varieties unique to the region.

The prefecture is home to historic landmarks such as Kumamoto Castle, one of Japan’s most impressive feudal fortresses, and Suizenji Jojuen, a beautifully landscaped garden. Traditional crafts like Higo zogan metal inlay and Yamaga lanterns highlight Kumamoto’s artistic heritage, while local festivals, such as the grand Yamaga Toro Matsuri, bring the region’s culture to life.

With its blend of breathtaking landscapes, deep-rooted traditions, and renowned cuisine, Kumamoto Prefecture remains a place where history and nature coexist, offering a rich and authentic experience of Japan’s southern charm.

About Kouro

The Kumamoto Sake Research Institute holds a unique dual identity—both as a pioneering research institution responsible for preserving and managing Kumamoto Yeast, the origin of Kyokai Yeast No. 9, and as the esteemed brewery behind the celebrated sake, Kouro.

Established in 1909 with the mission of elevating the quality of Kumamoto’s sake, the institute was founded at a turning point in the region’s brewing history. It was a time when Kumamoto’s traditional Akasake was giving way to the refined art of junmai sake brewing, inspiring local brewers to unite in their pursuit of innovation. Under the leadership of its first chief technician, Noshiro Kaneichi, the institute introduced groundbreaking techniques such as the Noshiro-style skylight, bag-hanging filtration, and the double-barrel method, shaping modern sake craftsmanship.

In 1952, Noshira successfully isolated and cultivated Kumamoto Yeast, later distributed nationwide as Kyokai Yeast No. 9, a game-changing discovery that continues to influence sake brewing across Japan.

At the heart of this legacy stands Tomohiro Morikawa, both brewmaster and head of production. "What sets us apart is our rare dual role as both a research institution and a brewery. By crafting sake ourselves, we gain invaluable data and firsthand experience that informs our innovations," Morikawa explains.

Each week, the brewery undertakes four separate fermentations, carefully analyzing the impact of different rice varieties, polishing ratios, and seasonal conditions. The production facility is thoughtfully designed to streamline every step—from steaming and koji-making to fermentation—ensuring precision and consistency.

"Great sake is not a product of chance but of deliberate craftsmanship," says Morikawa. This philosophy is embodied in the brewery’s signature Daiginjo Kouro, a sake revered across Japan—its refined, complex character earning it a reputation as a sought-after hidden gem among connoisseurs.