In recent years, the value of "aging" has been discovered in Japanese sake, just like in Western alcohol. Among them, Shimazaki Sake Brewery in Nasukarasuyama City, Tochigi Prefecture, has an established reputation for its aged sake, and is a rare sake brewery that ages sake for long periods of time in caves that can be considered natural cellars. We spoke to CEO Kenichi Shimazaki about his approach to aging and cave aging.

Sake brewing that doesn't forget its roots and the starting point of aging

One of Shimazaki Shuzo's main products is their flagship brand "Higashi Rikishi" regular sake (normal sake), named by the second-generation brewer, Shimazaki Kumakichi, who was a fan of sumo. As an area where agriculture was popular, after heavy labor the body craves a meal with plenty of salt. The regular sake, with its sweetness and umami that rivals that, was loved by the locals. Trends change with the times, and Shimazaki Shuzo, like many others, produces new sakes that keep up with the trends, but this regular sake, which is their roots, is committed to "tasting just like the old days" and protects the local flavor, with the support of those who have been drinking their sake for many years. This sake can be said to be Shimazaki Shuzo's "individuality."

At the same time, they are currently working energetically on aged sake. Since 45, they have been experimentally storing ginjo sake of a quality that can be entered into competitions. Initially, they stored it at room temperature in tanks, and Shimazaki jokes that "after a few years, we forgot that we were storing it, and then we remembered when we happened to run out of brewing tanks." However, when they unveiled the sake for the first time eight years later, it was well received. This marked the start of Shimazaki Sake Brewery's aging process. In the mid-8s, they commercialized the product and sold it to the general public. They also have a fully equipped cellar, and have established an aging style that involves room temperature aging followed by cellar management.

Aged sake sleeps in the cave brewery, waiting for time to come

Shimazaki Sake Brewery has made a big change in their aging method by starting "cave aging" in 11, using a cave near the brewery. This cave was built as a military factory for manufacturing tanks during World War II, but was abandoned when the war ended. Aging sake here is a rare initiative in Japan.

The cave, standing amidst lush nature, is a pitch black space with no sunlight penetrating. The temperature is kept at around 15℃ in summer and 5℃ in winter. As it was for military use, the internal structure allows outside air to be taken in and circulated, so it is not a completely constant temperature like a refrigerator. This slight change in temperature causes the sake in the bottle to gently fluctuate, allowing for better aging. The changes that occur at each temperature zone are born each time, giving the sake complexity. This is the natural power of the cellar that machines cannot produce. Before they started aging in the cave, they refrigerated the sake after aging it at room temperature, but now they are shifting to a style that allows for more thorough aging by using the temperature of the cave. They also want to convey the goodness of aging through a sake that is easy for people who are not used to it to try, rather than a sake that is typically "aged".

The cave is also open on certain days, and there is a system where you can enjoy experiences and stories, such as the "Owner's Bottle" where you can store your purchased Daiginjo sake in the cave for up to 20 years, and there are also suggestions to let you know the fun and deliciousness of the aging culture. Above all, the aged sake sleeping in the dimly lit cave, waiting for the time to wake up, is solemn and mysterious. It is definitely worth a visit.

SakeworldNFTAged sake featured in

East wrestler Cave bottle Soft mouth
Raw rice: Asahi's dream
Rice polishing rate: 70%
Sake meter value: -8
Acidity: 1.4
アルコール度数：13％
The Yawaguchi version of "Higashi Rikishi Cave Bingo" is a regular sake made using the Yamahai method, with a modest alcohol content of 13%. Pasteurization is also done in small batches, and the sake is aged in a cave for a certain period of time to maintain the best possible quality.

Higashi Rikishi Cave Bottle Special Junmai Delicious Dry Sake
Raw rice: Asahi no Yume and others
Rice polishing rate: 60%
Sake degree: +8
Acidity: 1.5
アルコール度数：14％
Similarly, Cave Binga's special junmai sake is made by blending the special junmai sake of the season with a further fermented mix of aged yamahai and fast-brewed seed sake, which is then aged in a cave.

Jukurokare Yamahai Junmai Genshu
Raw rice: Domestic rice
Rice polishing rate: 65%
Sake degree: + 1.5
Acidity: 1.8
アルコール度数：17％
The main brand of cave-aged sake is "Jukurokare." Yamahai Junmai Genshu is a sake with a complex and calm flavor. It shows different expressions when served cold or warm.

Jukurokare Junmai Ginjo Secret 5 Years
Raw rice: Domestic rice
Rice polishing rate: 60%
アルコール度数：15％
Junmai Ginjo Hizo 5 Years is a new product that will be released in April this year. Until now, long-aged sakes such as 4, 5, and 10 years have been available as Daiginjo, but this Junmai Ginjo, which has been kept in a cave, has been released after exactly five years. It is refreshing and smooth, and the more it is heated, the more full it becomes.

Jukurokare Daiginjo Secret 10 Years
Raw material rice: Yamada Nishiki
Rice polishing rate: 40%
Alcohol content: 17-18%
The 10-year-old secret daiginjo has an amber glow and a mellow, aged aroma like honey.

Jukurokare Daiginjo Secret 20 Years
Raw material rice: Yamada Nishiki
Rice polishing rate: 40%
Alcohol content: 17-18%
The Secret 20 Year Old has even greater depth of flavor and smoother texture.

"Jukurokare" is highly acclaimed, and if they continue to age it at the previous pace, production will not be able to keep up, so they are currently increasing their storage capacity for sake that will mature in the future.

At SakeworldNFT, these sakes will be kept in ice-controlled cellars at -5°C. While the temperature in Shimazaki Sake Brewery's caves changes slightly with the seasons, SakeworldNFT stores them at a constant, ultra-low temperature. It depends on the number of years, but if stored in SakeworldNFT's cellar, Shimazaki predicts, "The low temperature will mean the maturation process will take longer, but in return, I think the sake will be more refined and elegant." The very gradual maturation will leave behind the parts that you don't want to change, resulting in a refined sake. This looks set to be an easier sake to try for those new to aging.

SakeworldNFT"I want you to broaden the concept of aging."

Shimazaki-san said of his expectations for SakeworldNFT, "Sake breweries are working hard to popularize aged sake. Different breweries have different aging methods. I hope that SakeworldNFT will spread the concept and merits of aging. I hope that this will increase the value of 'aging sake' and also increase the value of each brewery's specialty aging method." He also expressed a hope to compare tasting with cave-aged sake, saying, "Once the aging at SakeworldNFT has improved,"

Taking on new challenges with a mix of technologies

When I asked Shimazaki Shuzo about their future plans, a number of interesting topics came up. First, the aging of low-alcohol sake. The current trend is to reduce alcohol, but many of these are fresh, with a sweet and sour taste. Therefore, they are trying to create a sake that does not feel thin by using aging techniques to add depth and mellowness to low-alcohol sake.

They are also apparently trying to mix the brewery's own unique characteristics by aging their regular sake, which is their roots, in caves and incorporating elements of regular sake into their designated name sake.

And the thing that surprised me the most was the botanical aged sake. The botanicals are soaked and extracted into the aged sake. It's not craft sake, nor is it a distilled liquor like craft spirits; it's quite an experimental attempt. I can't wait for the day when these will be available in stores.

With its traditions since its founding, the creation of a new concept for sake called aging, and the idea of ​​combining the two to create a hybrid, it may not be an exaggeration to say that Shimazaki Sake Brewery is the most "interesting" sake brewery right now.

Writer: Arika Takahashi
Living in Tokyo / Sake/Japanese writer, Japanese teacher, Sake taster
A writer and teacher who is active in the "two (Japanese) pillars" of Japanese and sake. Her favorite brand is ``Yamato Shizuku'' and she has a strong love for Akita Prefecture.
Other than alcohol, my hobbies are fashion and perfume. Qualifications: SAKE DIPLOMA, Sake Studies Instructor, Sake Master, Japanese Language Teaching Proficiency Test