Experimental, innovative, and originating from ancient Japanese culinary customs, koji coffee proves that the future of coffee may very well be in fermentation.
A fungus of staggering complexity, koji starts small—with its powerful conversion of starch to sugar occurring at the near-microscopic level—but it brings a powerful punch of flavor to the dishes it composes. While it’s no stranger on the table, forming the base of soy sauce and the briny bite of tsukemono pickles, and appears as a common feature in Japanese drinks (such as Japan’s national brewed beverage, sake) koji has primarily remained within the realm of Japanese cuisine.
However, as fermentation continues to enter the repertoire of intrepid culinary pioneers, such as Noma, the powerful mold has progressed to the international stage, and even one step further, into cups of coffee. And while the transformative power of fermentation has been a frontier dabbled in by coffee connoisseurs, from winemaking-inspired carbonic maceration to the natural process of organic fermentation occurring as coffee cherries dry, koji remains comparatively unexplored outside of select scenes.
From miso to macchiatos, this mighty mold might now be redefining what fermentation can mean, turning centuries-old koji culinary wisdom into the next wave of coffee innovation.
Read “Bold Mold: Exploring The World Of Koji In Coffee” on Sprudge Special Projects
This story original appeared on Sprudge Special Projects, in a feature from Tokyo-based journalist Taylor Bond.
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