TIP: S7E03 "Deadly Prep"
Distill. It’s a word.
Like a lot of words that get used in western languages, it is of Latin origin.
De = to (well, more like, “about, concerning, from”)
Stilla = Drop
More accurately “to drip”.
That is honestly a really great way to understand what’s going on with distillation, but we’ll get to that in a second.
Let’s say you’ve got a pot of water, and you start to heat it up. Little bubbles start to form on the bottom. It took me longer than I’d like to admit to realize that those aren’t air bubbles. They are bubbles of H2O that has changed phases from a liquid to a gas. I always just thought that the visible steam off the top was the water vapor and the bubbles were air. Nope. It’s all H2O.
Different chemicals go through that phase change at different temperatures, which is super duper convenient, because once you understand temperature and how to accurately measure it, and you also understand chemistry and how to test it, you can start using heat to separate specific chemicals from more complex mixtures.
Let’s say you take some grapes, and you gently step on them, or use a potato masher, or whatever you want to use. This is hypothetical, you could honestly be gently mashing them with a pair of crocs that you’ve put on your hands for all I care. Anyway, you filter off the pulp and you’re left with grape juice. You add some yeast to that grape juice and it begins to eat the sugars. When the yeast eats sugar, it turns it into two things: CO2 and C2H6O, otherwise known as Carbon Dioxide and Ethyl Alcohol respectively.
At a certain point the alcohol level in the grape juice ends up killing the yeast (You’d want to die too if you were swimming in your own poop). The percentage varies a lot based on the amount of sugar that you started with and the kind of yeast that are living in your grape juice, but I’d say that the range is somewhere between 7 and 16 percent, give or take. The rest is mostly water, and mix of other flavoring compounds like sugars and acids.
Let's heat this mixture up and see what happens.
Ethanol boils at about 78.37 °C or 173.07 °F
Water of course boils at 100 ºC or 212 ºF
So, if you bring your wine to about 180º F, and keep it there for a while, you end up vaporizing the ethanol first and most of the water and other heavy particles stay in the pot.
Of course, we don’t want that vapor to just float away, we want to trap it, and ideally, cool it back down into a liquid, somewhere else.
What we need is a still.
The most basic of still is a Single Pot Still (in chemistry, you might call this a Simple Still). The idea is indeed simple: On one side you have a pot where you heat your liquid. The top of the pot tapers upward, directing the steam into a horizontal pipe that away from the heat source. Thus, the steam travels away from the pot, it cools down and, wait for it... DRIPS down the other side into your mouth, or keg, or mason jar, or whatever, with a higher ABV (alcohol by volume) than before. You stop boiling once you’ve removed as much alcohol as you think existed in the original mixture, and then trash the left over.
Actually, you probably wouldn’t want to drink the stuff that first comes off a single pot still. Number one reason, because the first liquid to start dripping out of that pipe will be methanol. It boils at 64.7 ºC (148.5 ºF), and in pure form, about 10 mL will destroy your optic nerve and blind you… so yeah, maybe read a book before you do this at home, and not just my half assed article? Cool.
Second of all, once you start getting ethanol out of the still, it isn’t going to be very pure. Why not? Well, it’s complicated. It has to do something called the "Ideal Gas Law", which predicts that even though the water and other particles in the mixture are going to boil at higher temperatures than the methanol, a certain percentage of them will still begin to vaporize as the temperature increases.
With a Single Pot Still, three trips through the process will tend to get you somewhere in the ballpark of 70-80% ethanol, which is great, but you also wasted a lot of energy and time in the process.
There is another way…
It’s called a Fractional or Column Still.
Here’s how it works:
You start out with the same idea: liquid is heated and vapor begins to rise. However, in a column still, as you might have guessed, there is a column which has many perforated plates, or a mesh of copper, or some other filling for the vapor to pass over as it rises. Think about it like levels in a building, with a staircase. The staircase allows you to travel from one level to the next, but at each level, you get a chance to rest. That is essentially what happens in the still. Except when I say resting, I mean condensing. The steam rises, and then condenses, heats up again, rises, and then condenses at the next level. As this process goes on, the condensed liquid at each level has a higher and higher abv. At the top, you have the same process as the Pot Still, with a cooling pipe that condenses the vapor and drips it off into… whatever isn’t your mouth.
If you made it this far, you might be wondering why I spent so much damn time talking about the different types of distillation (by the way, there are other kinds, but I’ve wasted enough of your time already), well, it has to do with brandy.
And specifically, it has to do with two distinct types: Cognac and Armagnac.
Both of these are brandies that are distilled from grapes. They’re also both from France, each getting its name from the region of the country where it must be made. The differences lie in a few areas, one of them is how they’re distilled.
Cognac must be distilled in Single Pot Still, and it must be distilled at least twice, which tends to yield an abv of about 70%.
Armagnac on the other hand, must use a Column Still, and can only be distilled once, leaving it with an abv of about 52%.
There are other differences that we could very much nerd out about, but the implications of the distillation are the biggest factors, in my opinion.
Because Cognac is distilled twice, to a higher abv, you have a very clear spirit that in some ways has lost the little nuances from the grapes it started with. It benefits though, from being smoother (albeit with less character), and thus needing less time aging in a barrel before it’s ready to drink. Cognac is only required to hang out in a barrel for two years minimum.
Armagnac on the other hand, due to the use of a single, column still distillation run, ends up with a lower abv, but with a higher amount of “flavor” compounds. While these would be seen as adding “roughness” to a young spirit, if given time to age, these flavors can mellow into very distinct and unique taste. Thus, even though to my knowledge, they are not required to, most Armagnacs are aged substantially longer than Cognacs. Many of them meeting the qualifications for the title “Hors d'âge”, which must be at least 10 years old. Some go longer, up to 25 years.
This does have downsides. One is the "Angels Share", a term for the small amount of alcohol lost during the process of aging a spirit in wood. It is usually about .4% per year. So if an Armagnac starts at 52% alcohol, and ages 25 years, it will lose 10% of its abv, resulting in a final spirit at is 42% alcohol.
Because of that approximate abv, Armagnac is typically not “cut” with any water prior to bottling. Most other spirits, like bourbon which age in the barrel at 70-80%, and only stay there for 10 years tops, usually will end up cutting the spirit with water, so that the final product gets bottled around 45%.
I know that you just plowed through a HUGE knowledge bomb, and are tired, and want to drink some brandy, but before you do, here’s what you need to remember:
- Armagnac is column distilled, once.
- Cognac pot distilled, twice.
- Armagnac begins is life funky, and rough, but mellows over the long aging period.
- Cognac begins as a smoother spirit, thus doesn’t need as much time aging.
- Armagnac is somehow more difficult to say.
- Both of them are spelled dumb.
- That characters in Archer will be drinking Armagnac.
- You'll probably drink Cognac, because it's easier to find and tends to be a little bit cheaper.
Bourbon, straight out of the bottle.