Decant sake? Time to clear the air

The ubiquitous sight of sake served in ceramic or glass flasks along with matching o-choko cups is something that, regardless of modern sake styles and how westernized sake presentation becomes is something that is unlikely to disappear soon. The Japanese love tradition and part of sake’s appeal internationally seems to be the culture and tradition that goes with it. However it is important not to misinterpret the meaning or sometimes lack thereof behind these traditions. Recently I read an article which claimed the way a sake tastes can vary according to the way it is poured into the glass. Not the type of serving glass but the physical style of pouring….I’ll resist ranting on the nonsense behind this theory but what surprised me were the amount of online comments following the article where people figured this idea made sense as it was the same as “aerating” or “decanting” as is done with wine and therefore a sound theory. This surprised me for two reasons; firstly it is not at all the same as aerating or decanting. And secondly even if it was the same, why do so many believe that such practices would benefit sake?

Decanting in the wine world is done for two possible purposes. One is where the wine is gently poured into a secondary vessel to remove the wine from any sedimentary deposits that may be in the bottle. These deposits can impart astringent or bitter flavours to the wine so removing them is ideal – often required for unfiltered and/or particularly old wine. The other reason is pretty much the same as aerating. This is where the wine is transferred to a secondary vessel with a larger surface area exposing the wine to oxygen. The wine reacts to the air contact and is essentially oxidising (accelerating ageing) the wine. Wine is a fruit based liquid and if you recall basic science you’ll remember fruit reacts to oxygen (think of how an apple browns after it has been cut). This is effective when opening full bodied wines that are perhaps young or particularly concentrated in profile. The oxygen contact allows some of the robust aromas and flavours to settle. Also as most wine contains sulfites decanting can help some possible off-notes from the sulfur or even hints of cork smell evaporate. Of course as wine is fruit based, excessive oxygen contact will eventually turn the wine leaving an undesirable vinegary, dull taste. Hence an open bottle of wine is usually best consumed within three days, old wine much sooner whereas sake generally tends to last a few weeks, some will say even longer.
So now we have established the benefits of decanting/aerating wine, how could they benefit sake? Well, generally the only type of sake with sediment is nigorizake and that sediment is there for a reason. It adds texture, flavour and umami. If we wanted it out the brewer would have taken it out. So there’s no need to decant nigorizake. Other sake is mostly pressed clean. Nigorizake and slightly cloudy (usunigori) could technically be decanted clean but as the cloudiness doesn’t harm the flavour why would anyone bother? As for aerating, pouring sake into a glass and giving it a swirl will surely release more aromas and allow you to appreciate the bouquet of the sake but pouring it into a decanter similar to a wine decanter will do precious little for your sake. From experience, if anything the excessive air exposure will merely speed up the oxidisation of the sake resulting in dull aromas. As cork is not used as a closure and sulfites are not used in sake production there is again no concern for possible off aromas from these outside influences. An excessive ethanol alcohol aroma is possible but in many cases would easily be resolved from the aforementioned swirling in the glass. How about koshu or aged sake? Same issue as wine, as the closures are not 100% hermetically sealed, oxygen does find its way into the bottle slowly over time so exposing it to any more oxygen when opening it by decanting can be a gamble if left too long. Koshu that is aged in tanks also means ample air contact has already taken place.  True, decanting old wine may brush off some off the dusty aromas but in the case of sake not so much. Again, a swirl in the glass is all you need. Also take into account if you’re not going to finish the whole bottle in one sitting decanting the whole bottle is all the more pointless. Some may argue that young, brash shiboritate nama genshu with it’s high alcohol and concentrated flavours could benefit from aeration but robust concentrated flavours is what that style is all about so again why would you bother? The lack of fruit to react with the oxygen negates any real positive effect from deliberately exposing sake to air. In fact it’s this lack of fruit that prevents oxidisation from occurring too quickly. Once a bottle is opened sake will however eventually oxidise and turn. When this happens is open to debate. It depends on the sake and the drinker. If it is kept refrigerated some believe months after a bottle is opened it will still taste good if not quite different from when it was first opened. Others believe once those initial fresh flavours are gone so is the sake and a week or so is the most they would recommend. Personally, as a general rule I stick with around three weeks max. A bottle rarely lasts that long in my house anyway.

So back to those ceramic flasks (tokkuri). While I have actually heard them described as decanters whose function is the same as that of a wine decanter this is completely untrue. The tokkuri are used solely as a serving vessel to encourage drinkers to pour for each other as per Japanese drinking tradition. Although there are exceptions, tokkuri are usually quite narrow at the top which actually minimizes air contact making them quite useless as decanters.

Sake is a confusing beast to many consumers and introducing redundant serving and presentation practices helps no one. Let’s not over complicate it. Pour it in a glass, have a sniff, drink. Repeat.