So what is it about artisan or craft liquor that make it different from the ubiquitous mass-produced liquor found in every bar and package store. Simply, it is the differences, little and big that make the difference.
First and foremost are the stills. But who knew? Before I started studying stills, a still is a still is a still. Boil some liquid, collect the condensate, drink it. What's the difference? Of I couldn't have been more wrong.
Before proceeding with the differences between stills, let's take a half step back to discuss briefly the differences in alcohol. Probably not surprising, there are different types of alcohol. In the most basic sense, there is ethyl alcohol and methyl alcohol. Ethyl alcohol is the good stuff that lies at the heart of all beer, wine, and liquor. Ethyl is good, although tasteless. Methyl alcohol on the other hand is like ethyl's evil twin. Commonly called wood alcohol, consuming large quantities can cause blindness, other neurological problems, and death. Methyl is bad, although it has a taste.
The key to non-lethal distillation is to separate the good ethyl alcohol from the bad methyl alcohol and a few of its bad cousins. Fortunately, methyl alcohol is smaller, lighter, and therefore evaporates at 149 °F, whereas ethyl alcohol is heavier and evaporates at 172 °F. This difference in boiling temperatures results in the distillation of methyl alcohol before ethyl, although chemistry is never quite as simple and easy as one would like.
Anyways, back to stills, there are two basic types of stills, the alembic pot still or pot still, and the column still or reflux still. When most of us think about a still, it is the alembic pot still that comes to mind. There are ancient Egyptian painting that depict stills similar to alembic pot stills, and the alembic pot still as we know it today was invented in the 9th century in the middle east. It functions by boiling the fermented beer or wine in a sealed container with a tube leading off the top to a collection vessel. As the materials in the pot heat, different chemicals boil off at different temperatures (and therefore different times) allowing for the separation of compounds. As I summarized earlier, the bad methyl alcohol evaporates 23 °F cooler than the good ethyl alcohol. Therefore, by collecting and disposing of the first distillates from a run, also called the heads or cuts, the distiller is able to isolate the good ethyl alcohol from the bad methyl alcohol.
Unfortunately, as I said earlier, chemistry is never that simple and easy. Ethyl can combine with water to create compounds that evaporate at a lower temperature than methyl. There also are other minor volatiles that evaporate hotter and cooler than ethyl. The result is impure distillation of ethyl alcohol using an alembic pot still. To compensate for this shortcoming, it is necessary to redistill the ethyl alcohol rich distillate numerous times to further separate the good ethyl alcohol from all the other compounds in the beer or wine. Each subsequent distilling increases the percentage of ethyl alcohol inn the distillate up to near the theoretic maximum of about 90%. This process takes time, and therefore, is not the most efficient.
Column stills date back to the very beginning of the 9th century. They consist of a column (duh) in which the various volatile compounds collect at distinct heights based on their mass. By selectively drawing off the vapor from the different heights, ethyl alcohol is able to be separated from it's bad cousins efficiently in a single step in concentrations approaching the 90% theoretical yields. How the vapors are generated differentiate the type of column still. In it's simplest for, the column is affixed to the top of the alembic still. As the beer or wine inside the pot begins to boil, the vapors rise up the column and separate along the column by their mass. When the beer or wine was stripped of it's ethyl alcohol, the run ended and the still was cleaned. This type of column still commonly is referred to as a reflux still.
In the mid-19th century, an Irish distiller invented the continuous column still. It allowed for the continuous distillation of alcohol by removing the source of the alcohol from the pot. Instead, purified water was added to the pot, and the beer or wine was injected in a small continuous stream into the side of the column. The column is packed with material not unlike kitchen scrubbies. The hot steam from the water rises through the packing material and heats it. As the stream of beer and wine mixes with the steam and comes into contact with the warm packing material, the volatile compounds are stripped and they separate within the column by mass, with the lightest ones rising to the top and the heaviest settling towards the bottom. Again, in this single step, ethyl alcohol can be extracted to near the theoretical yields, but now in a continuous process that can run 24 hours a day without stop.
The vast majority of commercial, mass-produced liquor (excluding single malt scotch whiskies) are distilled today using the continuous column still technology. It allows for an efficient production of consistent quality ethyl alcohol. But the problem lies in the little fact that pure ethyl alcohol is flavorless. And good liquor is anything but flavorless. So what give?
The differences in the flavors of liquors are the result of the other volatile compounds that are captured along with the ethyl alcohol. Commercial, mass-produced distilleries compensate for the purity of their distillate by adding flavors after the fact. This is the reason we now see so many "flavored" liquors filling our store shelves. But added flavors typically ( to go back to my music analogy) contain only the major melody of the song. The minor melodies and supporting notes typically are lost. Another way to think of it is to think of the difference between smelling s rose, and smelling a rose-scented fragrance. The fragrance may still be identifiable as that of a rose, but the subtle nuances of a real rose are missing. Simply, expensive perfumes are expensive because they contain more body, more of the subtle undertones than do cheap perfumes. Similarly, what differentiates good whiskey from bad whiskey is not only the intensity of the major flavors, but also the subtleties and completeness of the undertones, the changes in flavor as it volatilizes on your tongue and up your nostrils.
As the Scots have not forgotten, the only true way to achieve the full symphony is to rely on the traditional ways of preparing the beer or wine, and to distill it in an alembic pot still.
Then comes the fun part. What differentiates one spirit distilled in a alembic pot still from another. Oh my gosh, you would not believe, and honestly, I think I shall wait to go into those differences until the next time.
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