My question is in regards to how distilleries mellow out their whiskey. How do they get ride of the harsh/burning sensation that is associated with bottom shelf whiskey?
The general consensuses is that whiskey does not age in the bottle. Rather whiskey can only age in a barrel. I suspect that one major reason for this is that a bottle is air tight. Or at least sufficiently air tight. Whereas a barrel is not air tight. Some whiskey (Angel share) evaporates over time. Alcohol is a larger chemical than oxygen. So if alcohol can get get out of the barrel, that means that oxygen must be able to get in. However, it is also generally accepted that most whiskey does not far well with oxidation in regards to whiskey that is left in a half open bottle.
Taking all of this into consideration. And taking out of consideration the effect that the oak has on taste. What is it about the barrel that makes whiskey age well? By "age well" I am referring to the act of whiskey becoming more "mellow" in term of losing the burning sensation. It seems that there there is something about the barrel that causes the whiskey to mellow out. I would assume that this has to do with the fact that the whiskey can breath in the barrel. But this would appear to have the same positive effect in a half empty bottle that is left out for several months or even years. But as previously stated, whiskey that is kept in a half empty bottles does not far well in regards to oxidization. Hence, the answer must not be that whiskey interacts with oxygen in the barrel. So, what is it about the barrel that is so special?
Un-aged clear whiskey generally tastes quit harsh. From my understanding the harsh taste comes from impurities within the whiskey. These impurities are taken out by re-distillation and filtering it through carbon. But even after re-distilling and filtering through carbon, some of these impurities still exist. these impurities are contributed to the harsh taste i.e. burning sensation of whiskey. Some how these impurities are released or changed with age. This leads me to believe that there must be some chemical reaction that can only take place in the barrel. So what is that chemical reaction?
I can come up with only two explanations. I am forced to discount the effects of oxidization since that can happen within the bottle. The first explanation is the the chemicals in the wood interact with the impurities and in some way neutralize them. The other explanation is that the barrels interact with sound in a different manner than glass. This theory involving sound comes from a chemist who claims to have come up with a way to mellow whiskey by using high frequency sound.
There is a new distiller in the U.S. (Cleveland whiskey) who has been getting a great deal of notoriety for his "new" method of speeding up the aging process. He does this by putting the whiskey along with oak chips in a device that puts the whiskey under a tremendous amount of pressure. This forces the whiskey deep inside the oak. In doing so extracting the flavor of the oak at a faster rate. This technique however is hardly "new." Many distillers have been practicing the art of "distressed aging" for quit some time. Distressed ageing is done by keeping the barrels in a hot environment. This causes the pours in the oak to open up, allowing the whiskey to penetrate deep inside the oak. The barrels are than put into a cold environment that than causes the oak to push out the whiskey. By "put into a cold environment" I am referring to the change in seasons.
This is why whiskey that is kept in the American South extract more flavor faster than whiskey that is kept in colder environments such as Scotland. However, I am not interested in how whiskey gets its flavor from oak. I already understand that. What I am interested in is how the whiskey is able to mellow out in the barrel and not in the bottle. Or does it?
There is however one more explanation. Whiskey is said to get 60-80% of its flavor from the oak. So the answer may well be that the whiskey in a barrel is in fact interacting with oxygen as it does in the bottle. But it is not losing its flavor since it is simultaneously interacting with the oak. Unlike with with a bottle where it is interacting with oxygen but is not interacting with the oak. The impurities that cause the burning sensation my also be evaporating along with the "angel share." Whereas with a bottle these impurities are not able to evaporate, but are able to interact with oxygen, "oxygenate."
I find this to be a fascinating question since to my knowladge no one has come up with an answer. Distilleries are constantly trying to fined new ways to speed up the aging process. They have succeeded to some degree; in that they have found ways to speed up the introduction of oak flavor. But how to they speed up the process of mellowing out whiskey?
I am asking this because I am interested in taking bottom shelf whiskey and rapidly decreasing the burning sensation associated with it. In doing so making it infinity more enjoyable in a relatively short amount of time. One may be concerned with the effect this would have on alcohol content. But this is of little worry to me since it would be done with a higher proof whiskey i.e. 65%.