Four Generations,
One Craft
From the snow country of Niigata to the sun-drenched hills of Napa Valley — the story of a family, a fermentation, and a bridge between worlds.
Takeshi “Tak” Yamamoto
Master Brewer · 4th Generation TojiTak grew up on the brewery floor in Niigata, watching his father and grandfather transform simple ingredients — rice, water, koji mold, and yeast — into extraordinary sake. By age eight, he could identify different sake grades by aroma alone. By fifteen, he was assisting with koji cultivation through the long, sleepless nights.
After earning a degree in fermentation science from Tokyo University of Agriculture, Tak spent twelve years as assistant toji at the family brewery. But a restlessness grew. He saw in California wine country a kindred spirit — a place where craft was celebrated, where terroir was revered, where tradition and innovation could coexist.
“My great-grandfather taught my grandfather. My grandfather taught my father. My father taught me. Now I teach California what sake can be.”
In 2016, with his father's blessing and a suitcase of koji starter culture — the same strain his family has cultivated for a century — Tak made the crossing. The result is Koji & Co.: a brewery that honors everything he inherited while embracing everything California offers.
A Century of Brewing
Yamamoto Shuzo is Founded
Tak's great-grandfather, Ichiro Yamamoto, establishes Yamamoto Shuzo in the snow country of Niigata Prefecture. Using pristine mountain spring water and locally grown rice, he begins a tradition of brewing clean, elegant sake.
Second Generation Takes the Helm
Tak's grandfather, Kenji Yamamoto, inherits the brewery. He modernizes equipment while preserving the handmade koji cultivation techniques that define the house style. The brewery earns its first gold medal at the Annual Japan Sake Awards.
The Pursuit of Perfection
Tak's father, Hiroshi Yamamoto, becomes toji. A perfectionist, he introduces precision temperature control to fermentation and experiments with higher rice polishing ratios. Under his guidance, Yamamoto Shuzo becomes known for its daiginjo — the pinnacle of sake brewing.
Tak Begins His Apprenticeship
After graduating from Tokyo University of Agriculture with a degree in fermentation science, Takeshi returns to Niigata to train under his father. For the next twelve years, he learns every aspect of the craft — from the precise timing of rice soaking to the intuitive art of koji cultivation.
A Dream Takes Shape
During a trip to California wine country, Tak is struck by the parallels between Napa Valley and Japan's sake regions — the obsession with terroir, the celebration of craft, the reverence for tradition. He begins planning what many consider impossible: a world-class sake brewery in the heart of wine country.
The Crossing
With his father's blessing and a suitcase of koji starter, Tak moves to Napa Valley. He discovers a century-old stone barn on the Silverado Trail and begins the painstaking conversion into a sake brewery. Locals are skeptical. Wine country making sake?
First Brew
Koji & Co. produces its first batch: a junmai ginjo using California-grown Calrose rice and Sierra Nevada snowmelt water. The result surprises even Tak — familiar Japanese precision with an unmistakable California character. A new chapter in American sake is born.
Today
A decade in, Koji & Co. is one of the most celebrated craft sake breweries in the United States. Five signature brews. A tasting room that draws visitors from around the world. And a fourth-generation toji who proved that great sake doesn't need a Japanese ZIP code — just a Japanese soul.
Ma — The Beauty of Space
In Japanese aesthetics, ma (間) refers to the negative space between things — the pause between notes in music, the emptiness in a room, the silence between words. It is not absence but presence. Not void but possibility.
This concept defines everything we do at Koji & Co. — from the breathing room between flavors in our sake, to the unhurried pace of our tasting room, to the generous space we give each stage of brewing. We believe the best things emerge when you give them room to exist.
Become part of our story
Visit our tasting room and taste the connection between Niigata and Napa for yourself.
Plan Your Visit