Let me start this article by saying; Oh my god, people die from this. People burn their houses down. People explode themselves. People poison themselves. Learn from this article. Use it to inform your upcoming scifi novel about space speakeasies during space prohibition. (Oh, it'll happen.) But don't actually do this.
Just to keep you from doing anything terrible, I'm going to teach you how to make corn alcohol. It's not tasty. One of the reasons why elaborate cocktails were invented was the taste of the alcohol made during Prohibition. It was so foul that even roaring twenties alcoholics needed something to distract themselves.
To start out, for any alcohol, you just need sugar and yeast. The yeast will consume and break down the sugar, and you will drink the fruit of the yeast's . . . digestion. If it sounds like something out of The Human Centipede, that's because it kind of is. But a lot of things you enjoy have been squirted out of a living thing at some point, so why start fighting it now? There are naturally occuring yeasts nearly everywhere, so all you have to do is supply the sugar. This can either be pure sugar, or molasses, or fruit, or, in this case, corn. First you need to soften and sprout the corn - or the wheat, or anything other grain you have. Put the corn in a slowly-draining vessel and cover it with warm water. Keep the vessel covered to keep out bacteria, and pour more water over it as the extra liquid drains out the bottom. This part takes a few days, all on its own.
Once sprouts have appeared, and grown an inch or two, drain the liquid, dry the corn, and grind it up. This makes all parts the corn accessible to the upcoming yeast. Pour boiling water over the corn to make a loose mixture, called a 'mash'. At that point, more sugar and yeast can be added. Neither is necessary. The corn has sugars in it, and natural yeasts as well. Adding more will speed up the process and change the taste of the resulting alcohol. It all depends on the kind of bootlegger you want to be.
Now just set it aside and let the yeast feast. It'll be about three days, if there's added sugar and yeast, but could be about a week and a half if the mash is on its own. The natural yeasts in the corn have to grow and spread, and that takes time. Keep the mash scrupulously clean and covered during this time. When it stops bubbling, it's ready. Or lying in wait for you. Whichever, really. Tasting a tiny bit of the mash at this point is possible, but not recommended. There's a lot of carbonic acid - also produced during fermentation - that makes it extremely sour. There are some other things in there as well, which will be covered shortly.
And finally it's time to cook. You need a covered vessel, a thermometer, and a tube that comes out of the lid of the covered vessel. That tube is at the beginning of a wonderful journey. First it climbs up high away from the cooking vessel. Then it spirals down through a container full of ice. Last, it pierces through the side of that ice-filled container to empty into a jug. This set up is very important.
As you heat the sealed pot of mash, the alcohol will start to boil. It will boil at a lower temperature than the rest of the liquid. Since it's boiling, it's turning to gas, and rising up through the tube. The way the tube rises high will help ensure that no other components are accidentally pushed upwards with the alcohol steam merely by chance. The gas has to rise and keep rising to get to the top of the tube. Then, as more steam pushes it, it gets shoved back downwards through the ice in the container. The ice cools it down fast, making it condense and leak out of the tube as liquid.
Boiling a substance means giving it enough energy to turn it to gas. Since the energy-filled gas moves away from the main body of liquid, the remaining liquid stays at a certain temperature. The process is like getting a group of people to run, and giving anyone who runs faster than five miles an hour wings to fly away. The remaining people on the ground can't be running at higher than five miles per hour. If anyone did, they'd be gone. They plateau at a certain speed. The moonshine should also plateau at certain temperatures. This is important, because ethanol is not the only alcohol that's produced. The fermentation process also produces methanol. Ethanol is in cocktails. Methanol is in antifreeze.
Fortunately for moonshiners, methanol boils at a much lower temperature than ethanol. It gets out of the mash at about 148 degrees Fahrenheit. By carefully monitoring the temperature of the mash, people can see the first plateau reached by the mixture. The methanol will evaporate out through the tube, condense, and drain away. Keep the heat steady so the mash stays at that point for as long as possible, until nothing more is leaking out of the tube. After all the methanol has been evaporated off, the temperature will start going up again, and plateau again at 173 degrees. This is the ethanol, the drinking alcohol. Keep an eye on the thermometer as that is collected in another container. When the temperature starts going up again, all the ethanol will have been harvested, and the moonshining (moonshination?) will have been successful.
In theory. Because no one is actually doing this. Let's be clear about that.