Sake Pasteurization - Fall Draft Sakes Are Called "Hiyaoroshi"
In 1569 an act by sake makers in Japan was recorded in a temple diary that changed sake production forever. These ingenious sake brewers realized that if they heated their efforts they would last longer - for shipping purposes. Huh? Yes - they found that a sake that they heated became far more stable and lasted longer as a sake in the form that they intended to make. Bingo! This meant that they could then send their sakes further and further away to larger and larger markets to meet more and more demand. Smart folks, eh? Heat acted as a preservative. This sake moment of enlightenment occurred roughly 300 years before a certain Frenchman by the name of Louis realized that heat could "pasteurize" other items of note.
Fast-forward 400 years to the year two amazing achievements occurred. Firstly, man took one giant leap for mankind and boot imprints decorated our friend the moon's surface. Secondly, and of equal importance (tongue meet cheek), the Japanese Brewer's Union banned the use of sulfites in the sake industry. Yup - guilty as charged - brewers used sulfites - and for proof check out older bottles of sake - pre 1969- and you will see the incrementing word!
So in today's sake market - Nama really symbolizes fresh sake! Typically a brew will be "rested" for 6-9 months before being released in one form or another. Why rest a brew? Sake that is just pressed tends to be bigger and edgier - rougher - a little louder. Resting it for a period takes the edge off and rounds out the final product. So is all nama sake brash and bold then? Nope - depends on how it is constructed and released - we just finished selling a summer released Nama Junmai Daiginjo from Umenishiki that you would be hard pressed to tell that it was unpasteurized if you didn't smell it. (Nama sake has what we in the biz call a "nama" nose - a brightness/yeastiness/greenish quality that is unmistakable - yes, time to smell your sake again!)
Are all Namas created equal? Come on man - they do not call the sake industry the "Industry of 10,000 methods" for nothing! No, not all Namas are equal! There are "versions" of Nama sake. For example a brewer can make a sake, bottle it, and release it immediately without pasteurization. This would be called nama-sake, nama-zake, hon-nama or even nama-nama. Point is - no heat whatsoever. There is another form of Nama called nama-chozo, which is a sake that was fermented and then stored for a spell - then hit with one "heating" before being bottled (or heated in the bottle) right before release - a once pasteurized sake. Why do they do this? Again - brewers make sake to taste like something for a reason - and they feel that if they hit that brew with a second heating then it won't taste like they want it to - (there is a generalization in the sake industry that for each pasteurization the sake essentially ages a year - think mellowing out - so a twice-heated brew would have the feeling or effect of laying it down for two years - remember, this is just a generalization!)
There is another form of Nama sake called nama-zume or Hiyaoroshi. This style of sake is different than Nama-chozo (once pasteurized) in the sense that brewers will ferment, press, then immediately pasteurize the brew once and rest it for 6 months - then bottle it for release without a second pasteurization! Nama-chozo equals ferment and store then heat right before bottling/release. Hiyaoroshi equals fermenting then heating once - then storing for 6 months - then bottling and releasing. Why do they do this? Why is one done before bottling and the other not? Style! It's all about the style of sake the producer wants to make. Is there a difference? Of course! Remember heating stabilizes the sake - it whacks the enzymes that in most cases alter the brew (usually for the worse). So in one form the sake is still active for +/- six months and in the other case it is not as active.
Some in the biz feel that Hiyaoroshi-style sakes are just a marketing exercise to get folks all lathered-up for their release in the fall. Others swear that these brews are made especially for Autumn flavored cuisines - including fattier fish. I am a sake romantic so I agree that they taste more full and round and have a certain richness - Autumn-like flavor and feel. One brewer said that he likens his Hiyaoroshi to a special "feeling" that is inspired by the Fall. Maybe you should try the "feeling" yourself by trying our just released line-up of Hiyaoroshi, which are featured in our New Store Arrivals section below.