What is koji? This beginner-friendly Koji 101 guide explores essential facts about Japan’s most important fermentation culture, from the science of enzymes to the delicious foods and seasonings it helps create.

Often overlooked in favour of sake itself, sake kasu is a nutrient-rich fermented food packed with flavour, history, and untapped potential. Discover why this humble by-product may be one of Japan’s most fascinating culinary treasures.

Think of enzymes as koji’s secret workforce: invisible, constantly working, and responsible for much of the sweetness, umami, and tenderness that make fermented foods so delicious.

Once a summer staple of the Edo period and now known as Japan’s “drinkable IV,” amazake is a traditional fermented rice drink prized for its gentle sweetness, nutritional value, and centuries of history.

All the biotics – made simpler

Fermentation does not only happen in jars and breweries—it also happens inside our own bodies. Discover how High MAC foods, fermented foods, and umami may help support the gut microbiota and shape our long-term health from within.

Shio-koji is far more than a trendy Japanese seasoning. Rich in enzymes and fermentation power, it tenderises meat, deepens umami, supports gut health, and quietly transforms ordinary ingredients into something exceptional.

Invisible to the naked eye, Aspergillus oryzae has helped shape the flavour of Japan. From sake and soy sauce to miso and shochu, this humble mould became one of the most important organisms in Japanese culinary history.

Umami is far more than a buzzword. It is the flavour that sustained Japan for centuries, inspired groundbreaking scientific discoveries, and is unlocked through the remarkable enzymes of koji mould itself.

1,000 years of imperial meat bans, a landscape of natural disasters, and a beer called Juice Rocket. We look at how Japan mastered the art of koji to flourish in the meatless millennium.

It’s hard to believe that such a benevolent mould could incite civil unrest, but in 1444, the ancient capital of Kyoto played host to the Bun-an Koji Riots.