What is Shochu?
& Nihonshu-do Science
Sake World Sake e-Newsletter
April 1, 2005
INSIDE THIS ISSUE:
– Shochu: The Sake That Isn’t (Except in Kagoshima)
– Nihonshu-do and the Science Behind It
– Sake Events & Announcements
– In the Archives
Shochu: The sake that isn’t (except in Kagoshima)
Over the past five years or so, Japan has been in the throes of a major shochu boom. It just won’t quit, much to the chagrin of sake brewers. Some confuse sake (or, more accurately, nihonshu) and shochu, but in fact they are totally different animals.
In short, shochu is distilled, whereas sake is brewed. Shochu is also made from one of several raw materials. The alcoholic content is usually about 25%, although sometimes it can be as high as 42% or more, as compared with sake’s 16% or so.
The range of raw materials from which shochu can be distilled includes rice, soba (buckwheat), and barley. There is even one island where there are a few places that make shochu from brown sugar. It can also be made from more obscure things like chestnuts and other grains like foxtail millet, whatever that is. Then, of course, there is the illustrious sweet potato from the Satsuma region, modern-day Kagoshima Prefecture. This little puppy, purple-ish when steamed, is the current grand poobah of shochu materials, leading to a large share of the most highly prized shochu made in Japan.
Each of these raw materials gives a very, very distinct flavor and aromatic profile to the final sake. These profiles run the gamut from smooth and light (such as that made from rice, or even sake kasu, the rice-based dregs from sake brewing) to peaty, earthy and strong (the aforementioned purple potato).
Shochu production is not unlike whiskey production in several ways. There is an initial fermentation, fairly rough and fast and taking place at relatively high temperatures. The resulting concoction is then distilled. With whiskey, as in beer, the fermentation begins with enzyme-rich malted barely. But in shochu, just like in sake, the enigmatic enzymes come courtesy of koji.
Koji is, at least in sake brewing, as most readers well know, rice inoculated with koji mold (aspergillus oryzae). However, in shochu production, they can begin with either rice-based koji or barley-based koji. The principle and function are the same: create lots of enzymes by working the mold into a starch-rich source. These enzymes will then dissolve those starches – as well as starches provided by the potatoes, buckwheat, barley, or foxtail millet (whatever that is) – into sugar for fermentation.
Back to that wretched boom. For the past several years, shochu has continued to enjoy double-digit growth in the Japanese beverage market. This includes the “honkaku-jochu” (“real thing”) versions, distilled once and from only one raw material, with their attendant character and quirkiness, to the multiply distilled stuff, clean white liquor that admittedly makes a fantastic mixer.
But things are a bit out of balance, methinks. So much so that the pesky purple potato from Kagoshima has become extremely expensive, as in several thousand yen per kilo. It’s like, “Pssst! It’s a potato!”
So, shochu: popular it is; sake it isn’t. Unless of course, you live in Kagoshima. This is because the word “sake” in Japanese can and does actually refer to all alcoholic beverages in general, although it most often refers to the rice-based brew that is the subject of this newsletter. But in some rural parts of Japan, like Kagoshima – the only prefecture in the Japanese archipelago that brews zero sake (i.e. makes only shochu) – when you walk into a drinking establishment and ask for sake, you will of course get shochu.
Like almost all such beverages throughout the world, shochu developed as it did as an expression of region, especially climate, cuisine and available raw materials. Perhaps the factor most affecting the development of shochu is weather. Brewing sake generally calls for relatively lower temperatures, but shochu can be distilled in the warmer regions like the southwest, especially the prefectures on the island of Kyushu.
Actually, shochu has its roots in either China or Korea, depending on who you ask, probably having come across during trading. But Japan then took the technology and modified it, applying it to a wide range of adjuncts beyond rice, leading to types of shochu found only in Japan, such as that made from the now-infamous Satsuma potato, buckwheat, and foxtail millet, whatever that is.
While some shochu is making its way overseas, rest assured that the best stuff is not making it outside of Japan. The most famous brands are hard to locate, and can be expensive when found. This is ironic considering shochu’s humble roots, since until this craze hit it was not exactly considered top shelf stuff.
And the boom is only just now starting to show some chinks in its armor. An article in an industry rag last week mentioned that the rate of expansion of “honkaku” shochu was finally beginning to slow down. The rate of expansion is beginning to slow. Oh no! What will they do!?!?
For the record, despite the apparent tone of my diction, I am *not* anti-shochu. It can indeed be very tasty stuff. I do from time to time enjoy an almost-peaty imo-jochu (potato shochu), or a smoother kome-jochu (rice shochu), or even on the very rare occasion that I can find it, some shochu made from foxtail millet, whatever that is. I am just very pro-sake, and the image-driven, foamy-mouthed fervor that many consumers show toward shochu is certainly taking its toll on the sake world. So, sake though it may not be, by all means try and enjoy.
Finally, in at least the US, you will also find “soju.” Soju is shochu from Korea, where it may have actually originated. Those that have actively worked at importing that and making it popular have done a thorough job of seeing that the word soju (moreso than the word shochu) has become fairly well known. As I have not tasted much of the product from Korea, I cannot comment on its flavor profile or enjoyableness.
Nihonshu-do and the science behind it
I have, in past editions of this newsletter, covered the topic of the nihonshu-do, most notably in its relationship to sweetness and dryness, especially in combination with acidity, and have also noted my personal opinions and reflections on the usefulness and applicability of this parameter. The March 2002 and April 2002 editions cover this in the most depth, and they can be viewed at the following link for those that are interested:
Fort those readers that missed those articles, or find themselves less than fully willing to fire up a web browser at this moment, here is the executive summary version: The nihonshu-do, also commonly known in English as the SMV (Sake Meter Value), is a number generally between -5 and +15 that indicates in a very general way the sweetness or dryness of a sake. What do you need to remember? Three things. 1) this number itself is only useful in its extreme manifestations 2) a gazillion other factors affect sweetness and dryness and 3) should you choose to pay attention to it, bear in mind this phrase: higher is dryer.
Most sake on the market hovers between -2 and +10. The former will be sweet, the latter will be dry. Still, no one on the planet can taste a sake and nail the difference between, say, a +4 and a +5. Because of this, and adding obfuscation to ambiguity, the nihonshu-do (or SMV) is only sometimes listed on the bottle. This invites confusion as to whether or not it is important at all, and does little to promote understanding. Yet, as it is far from a reliable indicator of either flavor profile or quality, I fully understand why many brewers don’t bother to list it, or why it will never be a legally required listing.
But all this evades a deceivingly obvious question: just what is it? Sure, it is a number, but what does it mean? Does it have a basis in modern science, or is it rooted in tribal beliefs and ethereal vibes?
In the end, it is very simple and scientific. The nihonshu-do expresses the density of the sake compared to that of pure water (a ratio known as the specific gravity). Why is this significant? Because, oversimplifying just a bit, the more sugar remains behind, the denser the liquid will be, and the sweeter it will taste. This is assuming a few boundary conditions such as a given alcohol content, since more alcohol would obviously thin out the mix.
The nihonshu-do is usually measured using a hydrometer, a calibrated float that sits in a glass tube filled with the liquid to me measured. Just how deep this float sinks shows how dense the liquid is. The float has a zero mark, and when this zero mark is just at the surface level of the liquid in the tube, it indicates a density equal to that of pure water. The numbers above zero are graduated and read +1, +2, and +3, etc, and the numbers below zero of course graduate down, reading -1, -2, and -3, and lower.
So if the float sits in thicker-than-water stuff, it rises, and the number read at the surface level will be negative. Likewise, if it is thinner than water, the float will sink, and the numbers read will be positive. This, then, is the source and explanation of the nihonshu-do numbers sometimes listed on the bottle. Those interested can see a picture or two at http://www.sake-world.com/html/smv.html.
Note, this parameter is used extensively during brewing. During the yeast starter (shubo) and fermenting mash (moromi) stages, there is obviously lots of sugar being spun off by the koji and rice constantly. While this is different than wine and beer production, in which you get all your sugar first before adding the yeast, it is still a very, very important gauge of how the process is proceeding.
Also, there is a direct mathematical connection to the baume scale used in wine making and the specific gravity readings used in brewing beer. Actually, there are two separate baume scales, one for liquids heavier than water (baume heavy) and one for liquids lighter than water (baume light). The nihonshu-do is identical to the baume heavy scale, but exactly ten times more precise. The zero point is of course identical, but after that, heavy baume 1 equals a nihonshu-do of -10, heavy baume 2 corresponds to a nihonshu-do of -20, and heavy baume 3 corresponds to a nihonshu-do of -30. Note, normally these large numbers only are seen during the sake brewing phase, as they indicate tons of sugar present.
And, in one final burst of math, nihonshu-do (SMV) is directly related to specific gravity by the following equation: Sp.Gr. = 1443/(1443 + SMV)
No, I do not know where those numbers come from (perhaps the aforementioned tribal beliefs) but I do know it works. Those with the requisite time, interest and geek-genes (like me) will notice that sake hovers both during brewing and in its final form in a fairly narrow range of specific gravity.
While all of this is certainly more than you need to know, and perhaps more than you care to know, just remember the executive summary above, and especially the phrase “higher is dryer,” and you will know all you need to know about the nihonshu-do.
Sake Events and Announcements
Sake and Pottery Seminar at Takara, April 30, 2005
On the evening of Saturday, April 30, Rob Yellin and I will hold a sake and pottery seminar at Takara, in Yurakucho.
The cost for the evening – half a dozen sake, ample food, a lecture and printed material – will be 7000 yen. Those interested can reserve a spot by sending me an email. No deposit is required. Takara is located on the B1 level of the Tokyo Forum, the convention center just outside Yurakucho Station. More detailed instructions for getting there will follow with the confirmation email.
In the Archives
At the risk of shameless self promotion, I want to encourage readers to scour the archives of this newsletter at http://www.sake-world.com/html/sw-archives.html for a wide range of topics that have been covered over the past five years in this newsletter.
The archives go back to August 1999. Within them are covered just about anything related to sake, from what it actually is (8/99, 6/03) to how it is made (9/99, 4/00, 7/04) to what makes for good ingredients (water: 2/01, 6/03, rice: 11/02, 3/03, and yeast: 10/99, 12/02). The topic of sake and region is covered, with articles on the sake of Niigata, Shimane, Fukui, Yamagata, Nara, Fukuoka, Ishikawa and Hyogo Prefectures. There are many more regions to be covered, but these are certainly worth knowing.
More focused, less general topics like un-pasteurized sake (11/99, 5/00, 7/03 and 12/04) and nigori-zake (10/03) are there, as are culturally supplanting topics like history (11/00, 7/02) and official government sponsored tasting contests (June or July of each year). Detailed (overly so?) discussions of processes like the yeast starter (8/00, 10/00) and its more interesting manifestations like yamahai (3/04) and kimoto (12/04) and pressing sake from the dregs after fermentation (4/01) along with discussions on aging sake (8/03) and warming sake (11/99, 10/03). And much more.
And while shameless self promotion is not usually my bag, being useful and informative is. I simply want readers to know the information is out there. Please check it all out at your leisure.