One of the most common questions that we get from folks new to distilling is, “Is it true that moonshine can make you go blind?”
No, moonshine does not make you go blind, but high doses of methanol certainly can. Unless you really screw up a batch, you should not end up with concentrations of methanol high enough to do any damage (other than give you a bad hangover). Let’s take a few moments to separate facts from myths of the of dangers of moonshine so that you can be 100% sure that methanol blindness won’t happen.
Methanol (also commonly referred to as methyl alcohol) is the nasty stuff that caused the notorious health concerns and lead to the blindness that everyone thinks is caused by moonshine. So how does methanol cause blindness? In its pure form, methanol is quite dangerous. As the methanol is processed by the liver, enzymes break it down into several different compounds, including formic acid and formaldehyde. It is believed that the formic acid is toxic to the optic nerve and is the primary cause of moonshine blindness, while the formaldehyde wreaks havoc on the rest of your nervous system.
How does Methanol end up in my wash?
Methanol is an organic compound that naturally occurs in certain fruits and vegetables. It can also be produced as a by-product by the yeast during fermentation, which typically happens the most in fruit washes that have a higher pectin content (you can use a pectic enzyme to try and remove as much of the pectin as possible).
Since it is a naturally occurring compound, however, both beer and wine also contain methanol, hence the myths of moonshine dangers. Wine (particularly reds) can have concentrations up to 329 mg/L and beer may have concentrations around 16 mg/L. As you can see (and as mentioned above), if you are distilling a fruit based wash, it potentially contains much more methanol so you may want to be extra generous with your foreshots (we will discuss foreshots more later).
If wine/beer have methanol in them also, why do people make such a big deal out of moonshine?
The big difference is that the methanol in beer or wine is evenly spread among the entire batch, but distillers are effectively concentrating most of the methanol in their batch into the first few milliliters that come out of the still. Since the boiling point of methanol (148.5° F) is much lower than the boiling point of ethanol (173.1° F), it boils off at the beginning and leaves everything behind the same way the ethanol boils off in the middle of the run, leaving everything else behind. These first drippings from your still are called the “foreshots” and if the concentration of methanol in your wash is high enough, taking a shot of the foreshots may very well be enough to be fatal… So instead, most distillers just dump about the first 50 ml per 5 gallons of wash down the drain (or set it aside to clean with).
However, what really got moonshine a bad name was illicit homemade moonshiners who didn’t give a hoot about the health of their customers as long as they were making a profit. Every once in a while, someone has no care for the quality of the product they are making and just for the quantity of the profit they are making. This leads them to add things to their moonshine that would make it stronger in the cheapest way possible. One of the ways they do this is by adding rubbing alcohol. By law, rubbing alcohol has to be denatured in order for the government not to tax it as a beverage and this is usually done by adding a poison, like methanol. See where this is going? Yes, people end up consuming large quantities of methanol due to the added rubbing alcohol.
So, if my wash alone doesn’t have much methanol in it, why should I care so much about it?
Methanol is one of the main components in alcoholic beverages that lead to bad hangovers. For example:
-Ever notice how bad hangovers from red wine can be? Now glance back up at the methanol concentrations I listed above….
-Ever notice how the hangovers from a high-quality vodka aren’t so bad? Well, since they are concerned with quality, they are probably doing a good job with removing all the nasty stuff.
A word of caution: There was once a batch of gin that was delicious as can be and resulted in almost no hangover. But trust me, you can definitely still drink too much of it….