Exploring the Various Styles of Aged Sake

Greetings Sake Lovers, welcome to another KURAND Magazine article that introduces you to the world of sake.

You may be wondering whether sake is matured like wine and to what extent it benefits from aging. Traditionally, sake is brewed to be consumed young, but aging is a surprisingly common practice nowadays. Even traditional styles often spend a few months in storage before shipping to knit the flavors together and balance out any erratic notes. In short, aged sake is a much more diverse product than you might think, and so, In this article, we will look at the range of styles available out there.

The Definition of Aged Sake

The general Japanese term for aged sake is koshu. The word is made up of the Chinese characters for old (古)and sake(酒). Another common label term for aged sake (although rarely printed in English) is choki jukuseishu, which literally translates to long term aged sake. It is the latter which this article will focus on.

Since the liquor tax law in Japan does not lay out an official definition for either, many brewers interpret these terms with a great deal of freedom. The Jukuseishu Kenkyukai (Vintage Sake Research Institute)—an organization comprised of retail stores, liquor stores, distributors, and sake brewing companies whose goal is to help spread the concept of long term aging and to increase brewing skills—has taken the liberty to create their own general definition for choki jukuseishu. Notice that the organization uses the word vintage, and not aged. This is because, in Japan, aged sake has a negative connotation, but this may be inviting confusion with the concept of the wine vintage.

Definition by Choki Jukuseishu Kenkyukai (Vintage Sake Research Institute)

There are some brewers that put the term on their label after just a year’s aging, but the group’s definition is seishu (sake), excluding sake with sugar added, that has undergone at least 3 full years maturation at the brewery. This is the definition that this article will adhere most closest to.

What to Expect from Aged Sake

So does sake benefit from such long aging and how do the flavors and aromas differ from that of wine, whiskey or any other matured alcohol beverages that you care to think of? First of all, aging sake is not quite as straightforward as aging wine. Due to the much more unstable microbiological makeup of sake, there are no hard and fast rules. Just like with wine, the aging results vary widely depending on the sake’s structure: acidity, body, sugar content, alcohol level, levels of bitterness and umami. For wine, each of these characteristics is determined by appellation, grape type, and production techniques used, but for sake, it is not quite as clear-cut.

Sake is categorized on a very basic level by its rice polishing ratio, but this alone does not determine the characteristics of the sake and with many brewers interpreting the system differently, this has become a very vague way to categorize sake, a vagueness that transcends into aged sake.

The sake service institute has tried to add some clarity by dividing sake up into 4 categories as follows:-

Kunshu: light, elegant sake with a delicate aroma (like daiginjo sake)
Soushu: light sake with a simple palate and a little sharpness (like hon jozo sake)
Junshu: sake with a modest aroma but more body and flavor (like junmai sake)
Jukushu: sake with a more mature aroma and excellent balance of bitterness and acidity

A large majority of choki jukuseishu on the market will fit very neatly into the final, Jukushu category, but there are just as many out there that won’t even come close.

Perhaps, once upon a time, all aged sake in Japan tasted like jukushu, but these days, as brewers play with the aging formula, more and more exceptions are hitting the shelves.

A More Detailed breakdown

The modern incarnation of choki jukuseishu (let’s call it that) can be broken down further into three more categories that take into account the grade of the sake and how it was made. The key difference between the three types is the speed at which oxidation and something called the Maillard reaction happens. The Maillard reaction is the breakdown of sugars and amino acids It is this reaction which causes the sake to change color when it ages.

Kojuku type
Honjozo sake and junmai matured at ambient temperatures. By aging at ambient temperature, the rate at which the color and aroma and taste change is accelerated. It quickly evolves, developing unique flavors and aromas that were not there before. Kojuku pairs really well with Chinese food, oily foods, and food with thick umami and sweetness (bitter chocolate, yakiniku, blue cheese, yakitori with sauce, curry).

Neutral type
This is often found among honjozo, junmai, ginjo, and daiginjo that have matured at both low and ambient temperatures. Combining both low and ambient temperature maturing yields a flavor somewhere between kojuku and awajuku. Good matches include sweet and sour pork, beef shabushabu, raisins, and chocolate. In general, it gets on well with and brings out the umami in foods that have a moderate amount of sweetness, sourness, and bitterness.

Awajuku type
This aging style is achieved by maturing highly aromatic sake like ginjo and daiginjo at super low temperatures. Rather miraculously, it retains the elegance of ginjo sake but the intensity of the aroma becomes slightly muted; the sake may develop bitterness but also more depth. It goes well with French food, sweet/low fat but has lots of umami components (raw ham, squid shiokara, roll cabbage, gratin, cheese).

The Charms of Choki Jukuseishu

Characteristics of Longer Aged Sake

The aroma of the longer aged sake is called jukuseika or koshuka and is sometimes compared to shaoxing, sherry wine, caramel, dried shiitake, and raisins. It is basically an oxidized aroma (a result of the sake coming into contact with oxygen). The color of the liquid is very characteristic and often reminds people of whiskey. Traditionally, sake is rarely aged in oak vessels like wine, but some brewers have begun to explore this too, in which case, you get hints of vanilla, butter, toast, etc.

Easier on the Body?

In fact, aged sake can have a peculiar sobering effect. In documents from the Edo period, it is written that “shinshu goes straight to your head while aged sake intoxicates your body in a much more satisfyingly pleasant way”. Even medical societies have published reports lauding how gentle aged sake is. For those trying to avoid a nasty hangover, aged sake just might be the answer.


The KURAND lineup often includes the odd aged sake or two. In fact, we have even produced original aged sake with our partner breweries. With branches all over Tokyo, each stocking over 100 types to taste to your heart’s content with no time limits, all for one flat fee, there is no better place to discover sake. We look forward to welcoming you soon.