20th century. In those days sake was shipped and sold in cedar casks, which had the side effect of imparting woody notes onto the sake. These days, taruzake is hardly standard fare, but Kiku Masamune in Kobe’s Nada brewing district has continued to make it, even employing coopers to craft the casks. Typically, sake is stored in the casks only for a couple days, so this is more of a flavoring than prolonged aging. (To read more about cask aging, see page 34.)
In the foreground is a bottle of Sawanotsuru’s honjozo aged sake that was brewed in 1973.
The maturation cellar at Masuda Tokubee Shoten, filled with ceramic jugs.
Masuda Tokubee Shoten brewer Guillaume Ozanne hails from Normandy in France and worked at French yogurt-maker Dannon, before moving to Japan.
The Return of Koshu
During the Edo period (1603–1868), records state that koshu was fetching two to three times more than other sake. It was a premium product. Samurai sake aficionados no doubt liked koshu’s savory and sweet flavors and were aware that to make koshu, you needed precious time. According to one Edo shopping guide from 1824, nine-year-old koshu (yes, there were age statements!) was more than double the cheapest koshu and three times the price of the least expensive new brew. But during the Meiji period (1868–1912) and the years that followed, old sake became a relic of the past.
“Now when we make sake, we are taxed on the sake we ship from the brewery,” says Hiroyuki Konno, the assistant brewing manager at Sawanotsuru. “But during the Meiji period, breweries were taxed on the sake they made.” That meant storing sake was a tax liability, and breweries began selling sake as soon as possible to recoup costs. In both the Russo-Japanese War and World War II, the Japanese government wanted sake breweries to make and sell as much sake as possible to pay for its military machine. During World War II, especially, when there were rice shortages forcing breweries to make imitation sake, aging sake was inconceivable. “In 1954, the law changed,” says Konno. “Breweries were taxed on what they shipped, but by that time everyone had forgotten about koshu.”
“This koshu dates from 1973,” says Konno. On a table in this meeting room are 11 bottles of koshu dating from 1973 to 2014. The sake comes in shades that you don’t typically see in sake—cream, amber, honey and marmalade. “Do you see these different hues?” Konno asks, holding up a glass of koshu from 1991. I take a sip. The flavors are more pronounced than in typical sake, and the aromas remind me of brandy or even whisky, though more reserved, and without the oak notes. I nose a 2010 junmai ginjo koshu: there are flowers and old books. The 2008 junmai daiginjo koshu is creamy vanilla. But in the background and the finish, there’s umami, and depending on the koshu, the savoriness can range from that of a light broth to a much deeper one reminiscent of soy sauce. At the end of the table are the older vintages. Light streams through a lace curtain, softly illuminating the koshu. I nose a 1973 junmai koshu. It’s like a delicious Sunday breakfast, with maple and pancakes. “We haven’t released that one just yet,” Konno says. “I think it needs more time.” I think it’s fantastic.
Today, koshu comprises just a tiny percentage of all sake. There are less than 30 breweries nationwide in Japan’s Association for Long Term Aged Sake, of which the Nada brewery Sawanotsuru is a member. The group defines jukusei koshu (matured koshu) as sake that has been aged for three years, because that that point the savory flavors and aromas are apparent. During its second year of maturation, the differences become noticeable, but this period is koshu’s awkward adolescent phase, and the changes are not necessarily for the better. By the third year, the savory flavors and aromas associated with koshu start to appear. Incidentally, this is also how long Scotch spirit must age in oak to be called whisky.
Stepping out of an elevator, Konno walks down a dark hallway to one of Sawanotsuru’s koshu cellars. Inside, it’s a cool 55°F (13°C) and the room is packed with 22 two-ton green enamel tanks. Koshu was originally aged in clay pots known as kame, so the enamel tanks might not be historically correct, but they do create an environment in which the sake can mature without its flavor being influenced. Rocks and cinder blocks sit on top of the tanks’ lids to keep them closed. At Sawanotsuru, junmai and futsu-shu are left to mature at room temperature. However, junmai ginjo sakes are in maturation rooms set to 59°F (15°C), while the delicate junmai daiginjo age at a lower temp of 41–50°F (5–10°C). The reason for this difference between room and low temperature maturation is the intent: Sawanotsuru wants to see how much junmai and futsu-shu change during aging, while the brewery wants to slowly age its premium ginjo and daiginjo for rounder flavors. Once it reaches the optimum flavor profile, like the 1973 vintage, it is stored in a maturation room at 41°F (5°C) to keep it from aging further.
Different styles of sake age differently. From left to right: a kimoto junmai from 2014, a junmai-shu from 1991, a junmai-shu from 1973, and a honjozo from 1973.
If there is no interaction with wood, where does Sawanotsuru’s koshu get its amber and brown hues? “A big difference between sake and distilled spirits is that if you leave, say, whisky alone, it won’t change color. Sake will.” The reason, says Konno, is that distilled spirits do not have components that will change color. “Sake changes its hue by simply leaving as is, because it has amino acids, organic acids and sugars.
“But after that, the sake starts to mature nicely, becoming richer and changing color as sake sediment collects at the bottom of the tank,” says Konno. “All that intensity reaches a peak, and then the sake settles down and becomes smooth and crisp to drink.” These changes happen over decades, and the brewers don’t just leave the sake to age in a temperature-controlled room. They check the flavors annually. Furthermore, every decade, depending on how the sake is maturing, they remove some—but not all—of the sediment, which consists of rice and yeast particles and other material, in a process known as oribiki, or “sediment removal.” The koshu is then placed in a new tank. “Here is the oldest batch in this maturation room,” Konno says, pointing to the date on a tank.
“Compared to vintage wine and old whiskies, koshu isn’t expensive at all,” says Konno. “That’s because people in Japan don’t yet fully appreciate its value.” Drink up while you can, because one day, that might change.
The Nada-gogo brewing district in Kobe is famous for its hard water (for more, see pages 90–91). However, its success was also due to local rivers like the Toga River (pictured) that helped power the waterwheels that made previously unseen rice-polishing rates possible for delicious sakes.
Hiroyuki Konno fills a glass with Sawanotsuru’s vintage sake.
THE MASTER CASK MAKER
“I’ve been making casks for over 30 years,” says master cooper Takeshi Tamura. Using a blade, he splits a long strip of bamboo down the middle. His movements are practiced and precise. He then takes the strip and whips it round
