Taste Testing The Cave Uroko Sake From Tochigi's Shimazaki Shuzo, The Legendary Cave Aged Sake! [島崎酒造 日本酒 洞窟貯蔵低温熟成酒 熟露枯 (うろこ)]

島崎酒造 日本酒 洞窟貯蔵低温熟成酒 熟露枯 （ うろこ ）

As Sake lovers continue to pursue the absolute frontiers of flavour, its breweries too have persisted in their search for new avenues to produce their Sakes in ways that not only deliver uniqueness, but push the envelope in terms of how Sakes can be made and developed. From next to absolute zero rice polishing ratios, to the use of flower yeasts, all the way to the co-ferments and fruited and spiced techniques favourited by craft Sake brewers, it's never been a more exciting time to be a Sake lover! 

Yet, one style remains as age-old as it is modern and relevant, that is, ageing. Ageing as a way to develop maturity, depth and mellowness of aromas, flavour and textures has existed since the dawn of time, and yet has for the most part eluded mainstream Sake for the better part of contemporary history, with fresher and more youthful styles typically the norm, where most Sakes are consumed within months, if not weeks or days even, of its making. Yet, as Sake has become increasingly demanded the world over, brewers have continued to pursue new flavours and have thus explored the area of Sake ageing. That said, this really only extends to just a minuscule group of brewers who have found resonance with the technique, and none more famous for cave aged Sakes than Tochigi Prefecture's Shimazaki Shuzo.

Shimazaki Shuzo.

Established in 1849 in the serene little city of Nasukarasuyama in the central Japanese prefecture of Tochigi just north of Tokyo, the Shimazaki Sake brewery sits close by to the local Naka River that runs downstream from Mt Nasu. The brewery has been making Sake for over 170 years, best known for its flagship Azuma Rikishi (東力士) brand of Sake which translates as "Sumo of the East", and was so named by the second-generation Shimazaki who had loved Sumo culture and had chosen the name to embody a spirit of being "unbeaten in a fight". The brewery makes use of not only well established Yamadanishiki and Gohyakumangoku rice, but also champions local Tochigi varieties, including Yumesasara and Tochigi no Hoshi (half of all the rice used by the brewery comes from within a 50km radius!), that is then brewed along with the subterranean waters that stems from Mt Nasu. Today the brewery is helmed by sixth-generation Shimazaki, Kenichi-san, who is responsible for a second coming for his family's brewery, that is cave aged Sake.

Having graduated from the prestigious Tokyo University of Agriculture studying brewing, Shimazaki-san would apprentice in Niigata before returning to helm his family's brewery. As far back as 1970, Shimazaki-san was already Intrigued by the concept of ageing Sakes and had initially sought to do so by allowing the Sakes to mature in tanks left at room temperature. Amusingly, Shimazaki-san would admit that after a few years of allowing the Ginjo-grade competition quality Sakes to age, he would completely forget about it and only return to it when he had finally run out of brewing tanks. Nevertheless, what he had returned to find was something so impressive that he decided to bottle it for sale. This debut batch of 8 year old Sake upon its release in the mid-1970's was to be met with great reviews, which would prove to be the encouragement Shimazaki-san needed to invest more heavily into aged Sakes. Shimazaki-san would figure that what he needed was a dedicated cellar that was cooler in temperature with smaller fluctuations, and had also ambient darkness that would ensure the Sakes were shielded through its years of ageing.

Shimazaki-san in the cave cellar.

Upon searching, Shimazaki-san would find an abandoned cellar carved into a nearby cave. Ranging 3.5 meters wide and high and 100 meters long, with three main tunnels interconnected by five 60 meter-long cross tunnels, the 600 meter long cave was originally made during World War II as a covert factory used to build military tanks but had since long been abandoned. Shimazaki-san would find that the cave had a temperature that ranged between 15℃ in summer to 5℃ in winter, which would allow the Sakes to mature slowly but more elegantly, whilst still keeping some variation unlike a fridge or industrial cellar. As it was man-made, it was also originally fitted with natural air flow circulation, which too would aid in the Sake's elevage. And so it was here that Shimazaki-san would create the now famous Cave Uroko Sake that is naturally cave-aged and at low temperature! If aged Sakes were rare to begin with, caved-aged Sakes are nothing short of a unicorn. 

Today, Shimazaki Shuzo has been producing its cave-aged Sakes for over five decades, and have become an important and cherished feature for locals, who have favoured Shimazaki's Owner's Bottles program, which allows customers to purchase their Sakes first but leave it with the brewery to age in the caves for anywhere between 5 to 20 years! Many of the brewery's fans have taken to the program as a way to celebrate important life milestones such as marking an anniversary or a child's graduation. The brewery also runs a shorter New Year's Bottles initiative where each year the brewery ages the newly brewed Sakes for just up until the subsequent new year when it's then delivered to those who've signed up, just in time for the festivities to begin. But for those who simply want a taste of the cave ageing effect without having to wait, Shimazaki of course offers up a range of their 1 year old, 3 year old and 5 year old Sakes at the brewery, which is a train stop away from the cave, and is also where the Sakes are brewed before being brought over to the caves.

These days Shimazaki's caves are lined with shelves holding on to these precious Sakes that have for many become treasured time capsules and meaningful keepsakes, many tagged with the well wishes of its owners or adorned with pictures of children or loved ones whose milestones the Sakes are dedicated to. It's also worth noting that visitors can not only visit the brewery but can even tour the caves too! The self-guided tours typically take anywhere from half an hour to longer, where visitors can leisurely explore the caves with also the guidance from a multi-language digital tablet that carries with it all the necessary information, which of course ends off with a selection of aged Sakes that are available for tasting and purchase.

A quick heads up for those in Singapore: Shimazaki Shuzo will be pouring its Cave Uroko range at Sake Festival Singapore 2026, organised by Orihara Singapore on Saturday, 20 June 2026 at Suntec City Convention and Exhibition Centre (Level 4, Hall 403).

Now in its 11th year and themed “Meet the Masters”, the festival is bringing over 40 brewers from Japan to Singapore for a one-day event with over 600 labels on pour. Tickets are available here!

And so with all that said, let's give Shimazaki Shuzo's legendary Cave Uroko Sake a taste! Let's go!

Sake Review: Cave Uroko Blended 5, Shimazaki Shuzo

Within Uroko's range of sakes, the Cave Uroko 5 is a blend of five different cave-aged sakes. Rather than ageing one vintage of Sake for a defined number of years, the Cave Uroko 5 blends five distinct cave-aged Sakes for an expression that is mellow and accessible at 15% ABV.

Tasting Notes

Colour: Clear, very pale straw.

Aroma: Fragrant, fruity and fresh. Soft melons come first, trailed by soft banana and the gentle white Saturn peaches, with a touch of muscat . There is honey here too and an umami rice porridge sweetness underneath. A clear bright almond note darts through the middle, and a little caramel and light honeysuckle florals at the edges. Holding all of it up is a soft minerality backbone and a soft crisp medium plus acidity.

Taste: On the more spiced, lightly drying side. A taru note and a dry cedar spiced note come through clearly, joined by light nuttiness and light spices that give it some grip. There is a bit of tart peaches and lactic acid woven in, and a clear ginjo-ka keeps the palate bright all the time. 

Finish: Fairly short, white peach sweetness fades first, leaving some clean vanillic woodiness and a fine mineral note; something close to wet stone. Right at the very end, a faint nutty oxidative warmth and a little dried dates.

My Thoughts

For an aged Sake this drinks with great freshness it almost feels like a nama! What stands out most is how very clean it is, and how it sits on the balanced and semi-dry side while having all that bright sweetness beginning with the nose. And it only shows its age in that last flicker of oxidative warmth on the finish.

The fruit and honey on the nose up front set you up for something richer, then the palate pulls back into something spiced and dry, with some interesting taru and cedar notes. It's layered, fresh, versatile and a really really easy Sake to enjoy.

@CharsiuCharlie