“Nihonshu” Now: Japanese Brewery Senkin Rewrites the Sake Rulebook

Nihonshu, unlike wine, is typically low in acidity, which is one of the reasons it goes so well with Japanese food. But Senkin Shuzō, a 200-year-old brewery, has turned conventional sake wisdom on its head with a tart, fruity sake offering the palate-cleansing crispness of a German Riesling.

Usui Kazuki, the eleventh hereditary head of Senkin Shuzō, was the driving force behind this innovation. After training as a sommelier, he returned home with some ideas that many initially found hard to swallow. Today, at the relatively young age of 37, he has secured a place as one of the key figures in Japan’s sake renaissance. His fans like to call him the “alchemist of acid.”

Flunking the Acid Test

Most nihonshu has an acidity level, or sando, between 1.1 and 1.5. Senkin, by contrast, measures between 2.0 and 2.3. Senkin is also substantially sweeter than the average nihonshu. The Japanese sake industry uses “sake meter value” (nihonshudo) to quantify dryness and sweetness, with positive values indicating dryness and negative values sweetness. Senkin’s SMV falls between –2 and –3, as compared with the nationwide average of around +1.5.

When Usui Kazuki first presented his tart new brew to a sake expert 10 years ago, he was greeted with derision. Acidity in sake was widely equated with spoilage or oxidation as a result of poorly controlled brewing or storage conditions. Moreover, this was a time when serious sake drinkers prized a clean, neutral taste, and most brewers were at pains to minimize both sweetness and acidity. “What happened, did your acidity meter break?” scoffed one taster.

“Granted, our technique was still a bit immature,” says Usui, “but the acid was no accident. It was premeditated. I was trying to attract attention to our brewery, which was on the verge of collapse.” Usui’s defiance of conventional wisdom was a kind of Hail Mary pass, a desperate and daring bid to save the family business.

Usui Kazuki, the eleventh-generation head and CEO of Senkin Shuzō (Domaine Senkin). Served in wine glasses, Senkin can stand in for white wine as an accompaniment to Western cuisine. (Photo courtesy of Niwa Cafe & Dining)

Return of the Prodigal Sommelier

Usui Kazuki was born in 1980. As the eldest son, he was expected to take over one day as the eleventh head of the family’s brewery, which had been making sake since 1806. The prospect did not excite him. Growing up he related more to the young urbanites featured in Japanese TV dramas who were always sipping wine in French restaurants. “To me, nihonshu was an old man’s drink,” he confesses. “It wasn’t cool.”

Usui became a devoted wine drinker. He ordered wine on dates and bought wine as presents. One of his heroes was Tasaki Shin’ya, who in 1995 had become the first Japanese to win first place in the International Sommelier Association’s Best Sommelier of the World competition.

hen he was 20, Usui dropped out of college and enrolled at the Japan Sommelier School (now the FBO Academy Tokyo). After a stint as a restaurant sommelier, he was hired as an instructor at the tender age of 22. When a mentor introduced Usui to a premium Fukushima sake, Hiroki he realized how good nihonshu could be—and how bad the sake back home was by comparison.

That realization, along with his father’s pleas, induced Usui to return home in 2003 to help turn the family brewery around. Unfortunately, the business entered a tailspin. For years, Senkin Shuzō had survived by selling cheap, mass-produced sake to a major sake company at a slim profit. Then, without warning, the manufacturer terminated the relationship, dealing a devastating blow to the 200-year-old brewery. 

Established in 1806, Senkin Shuzō brewery (in modern-day Sakura, Tochigi Prefecture) was built along the old Ōshu Kaidō, one of the five major routes of the Edo period. The masonry used in the building pictured is Ōya stone, a volcanic rock found only in Tochigi.

The Usui Brothers Go for Broke

In 2008, Senkin Shuzō was obliged to liquidate and start over under new management. Usui took charge of the new company as chief executive officer. His younger brother Masato, who had trained at a brewery in Yamanashi Prefecture, took over as tōji (brewmaster). Together they set about rebuilding the business as an artisanal brewery, focusing exclusively on small-batch premium sake. Their business strategy hinged on the development of a whole new style of sake, with acid as its defining feature. Usui explains their thinking.

“The younger generation wasn’t raised primarily on Japanese food,” he says. “They’re more accustomed to meat than fish, more at home with fried and sautéed foods than traditional simmered dishes or sashimi. They use ketchup and mayonnaise, and when they go out to eat, they’re likely to choose French, Italian, or ethnic cuisine. Conventional nihonshu is too low in acid to complement those flavors.

“Acid is a particularly important component of white wine. Acid doesn’t just provide tartness. It gives the beverage body and crispness and cleanses the palate. That’s important when you’re eating fattier dishes like meat, fried foods, and rich sauces. A typical low-acidity nihonshu can’t wash them down; the fatty flavor lingers on the tongue. That said, a beverage has to be balanced in flavor, not just sour. We decided to develop a new, contemporary style of nihonshu with a fruity, sweet-tart flavor profile comparable to the white wines of Alsace and Germany, and see what people thought of it.”

Owner-brewer Usui Kazuki uses touch, as well as sight and smell, to monitor the development of kōji mold on steamed rice, a critical step in the sake-brewing process.

The initial response was hardly encouraging. Usui’s father, who had left the business in his son’s hands, gave the new Senkin a thumbs-down. In fact, sake experts and older drinkers were virtually unanimous in their disapproval. “It was a generation gap,” concludes Usui. The kind of acidic beverage that goes so well with Western food can easily overwhelm the light, subtly seasoned Japanese cooking on which the older generation was raised.

But Usui was not ready to give up. He set up a tasting booth at various public events, and the results were eye-opening. Young women who would rarely if ever order nihonshu in a restaurant were clustering around the Senkin booth and draining their glasses amid exclamations of “Oishii!”

Why did it fall to young women to give the struggling brewery the boost it needed? One reason may be that women tend to have fewer prejudices when it comes to food and drink. While men often defer to established authority in matters of taste, women eagerly go after the things they like. Senkin was an obscure brand with no particular prestige, but it was exactly what these women were looking for.

From there, the buzz spread to other demographic groups. Wine lovers and foreigners in Japan soon discovered Senkin’s special appeal. The new style of sake that Usui had imagined as a sommelier and created with his brother was expanding sake’s fan base and carving out a whole new market for nihonshu. The gamble paid off, and before long, the company was out of the woods. In the first 10 years, production jumped 100-fold to 360 kiloliters.

Back to Basics

Senkin’s bold redefinition of nihonshu is one of the great success stories of Japan’s sake renaissance. But the brewery has not rested on its laurels. For one thing, the Usui brothers are determined to enhance the quality of their flagship product. This means scrupulously controlling each stage of the process, including filtration and pasteurization, to prevent any random or accidental production of acids and other compounds. Usui is after a “pure, clear, sparkling” acidity with a refined texture. “I’m focusing on mouthfeel as well as flavor and aroma in order to further elevate the quality of this sake,” says Usui.

Tōji Usui Masato uses the time-consuming binkan hiire process to pasteurize the sake in the bottle. By first heating the bottles to 63℃– 64℃ and then cooling them quickly in ice water, he kills microorganisms and deactivates enzymes without sacrificing flavor.

Meanwhile, the brothers have embraced another challenge, one that might best be described as “back to basics” brewing. Their new philosophy is embodied in their Senkin Nature line, brewed using all-natural methods and local ingredients. The rice is an heirloom variety of sake rice organically grown on a nearby farm. The seimai buai—that is, the fraction of the original weight remaining after the rice is milled—is a full 90%, and this at a time when most brewers of premium sake polish their rice down to 60% or less. Furthermore, the Usui brothers have revived the ancient kimoto method(※1), which relies on naturally occurring lactobacilli (the same microorganisms responsible for the fermentation of pickles) instead of the artificial addition of lactic acid. This technique involves a labor-intensive process of mixing and mashing (moto-suri) but is said to yield a more earthy, full-bodied, richly acidic sake. The water used in brewing is from the same source as that used to grow the rice, and no brewer’s yeast is added. Fermentation occurs naturally in old-fashioned wooden tanks. It may be the last word in natural, artisanal, labor-intensive sake brewing.

The traditional shizuku-dori method of pressing, using cloth bags, is reserved for top-quality sake. Senkin keeps the equipment refrigerated to prevent oxidation.

From left to right, Domaine Senkin’s “Nature,” “Modern,” and classic “Senkin” lines. (Senkin means “crane,” and the “Nature” label depicts a folded-up origami crane.) The brewery uses distinct varieties of rice, as well as different brewing processes, for each sake.

As of this writing, Domaine Senkin offers three types of sake, each made with different rice varieties and brewing methods: Modern, with its juicy, sweet-tart flavor profile; Classic, with its transparency and balance of acid, sugar, and umami; and Nature, with its vibrant natural acidity. And the Usui brothers are not stopping there.

“We launched this wildly unconventional sake in a pretty hostile environment,” observes Usui. “It was a cold start, but we got a boost from some enthusiastic fans, and now we’re picking up speed. We don’t want to disappoint anyone, so we’re going to keep working hard to develop delicious new sakes with an edge.”

Stay tuned . . .

(Banner photo: Usui Kazuki, CEO of Domaine Senkin (right), and his brewmaster Usui Masato. Behind them, Senkin Nature ferments naturally in wooden vats. All photos by Sandō Atsuko unless otherwise noted.)