Omachi-Mai: The Phantom Sake Rice
Updated: Jul 7, 2019
When it comes to brewers rice, one variety consistently steals the limelight. Originally bred by agriculturists in 1936 for the specific purpose of brewing sake, the mighty Yamada-Nishiki (山田錦) has a reputation for being strong, predictable for the brewers, and slightly easier to grow in comparison to some other sake rice varieties. As a result, it has long been considered the ultimate brewer's rice, and therefore shouldn't come as much of a surprise that this champion-supreme enjoys the title as Japan's most widely used for premium sake production. However, there is an old veteran that has been enjoying a resurgence of late, a purebreed that happens to be the oldest surving strain of sake rice, and that has been continuously cultivated since it was first planted back in 1859. That rice is of course the notorious Omachi-mai (雄町米) from Okayama Prefecture in western Japan.
In recent years, the popularity of this pure strain rice has been steadily garnering a loyal, almost cult-like following of admirers from amongst brewers and sake fans alike. So enthusiastic are these fellows that someone somewhere decided to label them with the term Omachists, a moniker that they now carry with pride when asked what type of sake they like. Master brewer Philip Harper has provided a very relatable analogy to explain Omachi's place amongst the many different rice varieties, stating "If Yamada-Nishiki is the Windows of Sake, Omachi is surely the only contender with enough charisma to qualify as a candidate for Macintosh". But what exactly is so appealing about Omachi, and why isn't it more widely grown if it's so special? The answers to both of these questions are intrinsically linked to the characteristics and composition of the rice.
Let's start with the possible reasons why it isn't as widely grown as Yamada-Nishiki. Firstly, Omachi is notoriously temperamental during both cultivation and at several key stages of the brewing process. It is a large grain rice which produces a superb white-core, or shinpaku (心白) in Japanese. The presence of this translucent centre is hugely favourable at the all important koji making stage as it aids the spores in their quest to penetrate the rice and grow. However the downside to this is that it comes from a very tall stalk which causes various difficulties and stress for the rice farmers. To put it into context, typical table rice comes from a stalk that grows to somewhere in the region of 70 to 90 centimetres. In comparison, Yamada-Nishiki, itself considered a very tall variety, can grow to over 100 centimetres. Typically late harvesting, rice with tall stalks are both very difficult to machine harvest and are often prone to breaking during Japan's menacing typhoon season. When you then consider that Omachi can grow as tall as a whopping 150 centimetres you get some idea of the problems farmers face during cultivation. So rare did Omachi become at one stage because of these difficulties that it gained the nickname maboroshi on sakemai (幻の酒米) which can be loosly translated as "the phantom rice".
Unpolished (genmai) Omachi rice from Okayama
In regards to the brewers troubles, although the aforementioned large shinpaku is great when making koji, it causes many problems during the earlier stages that proceed this. For example, Omachi is said to have one of the softest rice grains, meaning that they are prone to breaking, especially when polishing down to the levels required for the premium classification of sake. Furthermore, although the Shinpaku is big and prominent, it is also round as appose to the more oval shape of Yamada-Nishiki. This can make it much more nerve-wracking for the brewer when polishing the rice down to the super-premium classifications of ginjo and dai-ginjo. Finally, Omachi can be a real handful during the often overlooked, yet crucially important, stage of soaking the rice in preparation for steaming (浸漬). As it is soft, it absorbs water at an incredibly fast rate, meaning it is much easier to get the timings wrong, resulting in numerous other issues further down the line. Indeed, much of the brewers grumblings probably come as a result of struggling to get the perfect rate of water absorption (給水度) which is so crucial to making good koji.
However, that's enough of the negatives. Let's look at how Omachi, and it really is only Omachi, manages to attract such a passionate following and stand out from amongst the numerous other rice varieties. In doing so, I would like to make my own analogy by likening Omachi to an elegant classic car, and Yamada-Nishiki to its slick modern counterpart. The classic car will more often than not cause you no end of grief and stress. Will it start today? Will it break down during the journey? etc etc. Conversely, a modern car is dependable, robust, and easy to live with. However, ask anyone who has owned a classic to explain why they go through all the grief and they will no doubt tell you that it's because they just have a certain something, something more visceral and characterful than any modern car can compete with. In a strange way, you end up loving them more precisely because of their little faults and quirks.
Dropping the analogies, the real payoff for enduring all of Omachi's difficulties is that brewers are often rewarded with sake that cannot be easily replicated using other rice varieties. For example, in contrast to say Yamada-Nishiki, which will often produces sake with big bold flavours, Omachi is notable for more subtle or restrained flavours. Often you will hear terms like herbal, earthy, or even flowery when people describe the aromas and tastes of Omachi. Therefore, these characteristics often allow sake made from Omachi to stand-out from the crowd, and offer consumers an alternative from the wave of premium varieties made from Yamada-Nishiki. Judging by the fact that Omachi has reached the point where there isn't enough supply to satisfy the demand of the brewers, the signs are all there that this rice is continuing to grow in popularity. As someone who believes that nihonshu has now reached a point where it needs to further expand its fan-base from just the fruity-loving ginjo-ists, perhaps towards more nuanced styles with lower polishing ratios, Omachi could be the perfect variety to spearhead this change.