Welcome to another edition of KURAND’s series explaining the meaning behind various sake terms.
This time we explain the meaning of koshu (vintage sake).
With a flavor like brandy, and a very distinct aroma that is the polar opposite of just-filtered / pressed new sake (shinshu), koshu comes in a range of complex styles. Let’s have a look at some of the more common styles of koshu.
Koshu has no Clearcut Definition
First, koshu does not having an exact definition
In fact, just like shochu and awamori (two of Japan’s indigenous distilled beverages), koshu is itself a category.
The term koshu is normally attached to sake produced in the previous year. Sake that produced during the current year is called shinshu and sake produced over more than one year ago is sometimes labelled as daikoshu (lit: super vintage sake).
The definition is very broad and there are no terms to differentiate between koshu of different ages, so always check the date of production and find out how long ago it was produced. Identifying this is the key to finding a koshu to suit personal taste.
Chouki Jyukusei Sake
While the definition of koshu is indeed broad, there is an organization of koshu manufacturers, chouki jyukusei sake kenkyukai, that have devised their own definition for koshu as seishu (filtered sake) that has been aged for over three full years in a brewery. Unlike koshu and daikoshu introduced earlier, this is a clear definition so it’s a good thing to look out for when ordering or purchasing sake.
The History of Koshu, A Once Valuable Commodity?
From the Kamakura period up until the Edo period, koshu was actually extremely valuable.
Sadly that ended after the Meiji period. The Meiji government implemented zoukokuzei (brewing tax) charging it to breweries even before any sake had been sold, just for the privilege of brewing. There was no incentive for storing sake to mature as every sake had to be sold immediately upon completion to help cover the high cost of brewing it in the first place.
Eventually, zoukoku-zei was changed to kuradashi-zei which changed the timing of the levy until after the sake had been shipped from the brewery. The fact that breweries could waylay paying tax on completed sake and develop its flavour was incentive enough to revive the trend in vintage sake. Little by little, koshu is becoming a thing again. It’s perception has been transformed.
Characteristics and Taste of Koshu
The taste and characteristics of koshu are the polar opposite to shinshu (new sake).
The color is often much darker, close to amber, and the difference is easier to see than in fresh sake. It tends to be on the sweeter side as a result of oxidation (break down of sugars and amino acids / Maillard reaction) — there may even be hints of cacao, caramel or cinnamon.
Note: Whether or not sake changes colour as it ages depends on various factors, the most important one being temperature. The lower temperature the slower the Maillard reaction and breakdown of components, the slower the colour change. There are even transparent vintage sakes out there that are years old.
Some people even compare it to Sherry wine or Shaoxing Wine (fermented Chinese wine) and a wine glass is a great vessel to enjoy the aromas.
Modern koshu for a much more diverse experience of sake!
While the basic process of making koshu is the same as it was all those years ago and is essentially breakdown of sugars, amino acids and other components through oxidation and component reduction, some brewers are turning to technology to remove the risk from ageing and perfect the process. KURAND recently teamed up with a partner brewery and created a vintage sake that pairs with chocolate. Actually, vintage sake often makes for a great alternative to dessert wines like Eiswein, and fortified wines etc.
So there you have it, vintage sake is a treasure chest of complex styles that really opens the door to another dimension of sake, another dimension in the time and space of sake.
Sometimes the fridges at KURAND showcase vintage sake, so why not pop by and widen your horizons. We look forward to welcoming on your next visit!