Today’s Mr. Science’s Drunken Science is going to be as much drunken history as science. The question came in from Kilo in a past comments section:
“Would love to know the difference between good alcohol / ethanol and bad. Occurs in booze and beer. Bad booze can make you blind, and we better all know how to identify that shit.”
There is a long history of myth and cautionary legends around liquor. They are especially prevalent with regard to the history of Prohibition and clandestine liquor that was made by greedy, unscrupulous, or just plain stupid folks for the illicit market. I have a heavy interest in distilling practices and am still to this day surprised at how many well-informed people mention poisoning and blindness in regard to small batch liquor. Well, let’s clear this up a bit, shall we?
The blindness problem pretty much revolves around the compound methanol. Methanol is in fact an alcohol. Note the “-ol” at the end of a bunch of words that I plan on using. That indicates an alcohol. Alcohols are a family of molecules that are defined by a hydroxyl group (an oxygen atom bonded to a hydrogen atom) attached to a saturated carbon atom. In a simple sense, carbon likes to bond with four other things. This bonding makes carbon happy. So in a simple alcohol, you have a hydroxyl on one of those binding spots and three other atoms or groups attached. As long as all four spots are filled, the carbon is “saturated.” In the (sick and depraved) mind of an organic chemist, one hydroxyl group attached to a chain of x saturated carbons is some sort of alcohol. Methanol is the simplest of alcohols – CH3OH – one hydroxyl and one carbon saturated with three hydrogens. Ethanol, the one that is not as poisonous and also the one that gets us all fucked up, is CH3CH2OH or C2H6O. There are longer chain alcohols like propanol and butanol and on and on.
So that is a crash course in what makes an alcohol an alcohol. For the most part, the simple alcohols are found in nature and can be synthesized from natural products through distillation or fermentation. (Ask me sometime about the project I worked on that was related to bacterial production of butanol. Butyric acid makes puke taste and smell so – pukey. Gross.) Ethanol, of course, is produced by Saccharomyces and Brettanomyces yeasts and has been part of our culture for millennia. What is not commonly known is that fermentation by Saccharomyces species also produces small amounts of methanol. Pectin, a polysaccharide that is found in the structural elements of plants, is acted upon during the fermentation process to form methanol. Pectin is found in all land plants in varying amounts. Even the barley and other grains that we use in beer and liquor production contain a small amount, leading to a trace of methanol in all sorts of beverages. Don’t worry about it though, there are many chemical compounds created by yeast during fermentation and not all of them (including ethanol) are safe in large quantities.
“Alright, Mr. Drunken Science. That’s great. I am bored to tears with all of your organic chemistry. Get to the good part. What makes you go blind?” is something you might be saying to your computer right now. Which is weird. Well, it’s going to require a bit more chemistry. Really, methanol itself is not that poisonous. The bad part happens when you start to metabolize it. When you consume methanol, the enzyme alcohol dehydrogenase starts breaking it down. Unfortunately, the product here is formaldehyde. Nasty shit. Then another liver enzyme, aldehyde dehydrogenase, breaks that down even further into formic acid. Extra nasty shit. It takes the body forever to break this stuff down, and in the meantime it goes to work poisoning you. This stuff ruins the central nervous system. All sorts of shit happens including acidosis, Parkinson’s-like tremors, ataxia and after a while coma and death. The optic nerve is a prime target and can be destroyed, causing blindness. Look, all things considered, don’t drink the shit.
As we can see, methanol is bad stuff. The warnings I’m sure you’ve heard have some basis in reality, though they are generally more myth and legend at this point. Why do we still laugh and use the phrase “that shit will make you go blind” when we drink strong cheap booze? Well it goes back to the days of Prohibition. The Great Experiment led to a lot of little experiments, and some of them didn’t go so well. Even before Prohibition, we saw a lot of backroom production of booze. When liquor was deemed illicit, more and more people turned into homegrown distillers. These folks were motivated by need, greed or a desire to cash in on the inflated black market. Some were good at what they did while others were just plain dangerous. Regardless, there were a lot of factors that led people to produce and inflict adulterated hooch on the speakeasy set.
Methanol found its way into the jugs and glasses accidentally and on purpose. The more “innocent” ways included liquor that was made in a hurry. During the process of distillation, methanol and other fusel compounds are eliminated right at the beginning of the process. Methanol, since it is one carbon atom smaller than ethanol, is evaporated first. The condensation of the methanol-containing vapor can be collected and discarded. To a distiller, this liquid is called the foreshots. There should be little to none of the foreshots present in a final product. (Yes home-distillers, I can hear you getting fired up about foreshots, heads, hearts, and tails but we can address your concerns later.) When some outlaw distillers began to produce in bulk, the foreshots began to add up to a sizable percentage of product and they would neglect to discard these poisonous compounds since volume and time equated to money. When this type of liquor made it to market, the hangovers and gut-rot would be severe and in some cases, depending on the concentration of methanol, could be very hazardous.
There is also considerable anecdotal evidence that people were buying cheap (and legal at the time) denatured alcohol and adding that to their homemade booze to bolster it and give it more bang for the buck. Denatured alcohol is industrial ethanol, pure and wonderful, that has been adulterated with methanol to prevent human consumption. It is meant to be used in many aspects of industrial manufacturing, without the high vice taxes that are levied on pure ethanol. You could survive drinking this stuff. You could get a good buzz, but again, if the concentration fell on the side of too much, your eyesight and life were at risk.
Likely, incidents like these were very few and far between. The media and temperance movement grabbed on to them and sensationalized them to the point that they became ingrained in our popular culture, leading to the unfounded concern that probably still plays a large part in the illegality of distilling at home. That is not to say that the incidents do not still happen. Just a few days ago, an Australian kid died at a bar in Bali from some badly produced local hooch. That is definitely out of the ordinary, however.
Going back to the original question, there is not an easy way to identify “bad” liquor. Methanol smells a lot like ethanol and is perfectly clear. My advice would be to ask a few questions the next time you are offered some clear likker out of a jar. Don’t turn it down by any means, but make sure the hillbilly knows what he is doing. You could also give a shot to his dog and wait a few minutes to see if it is safe.