Using Your Still to Make Alcohol

Once the still is up to temperature, and the distillate has started dripping, make sure you throw away the first 50 mL per 20 L of wash, as this may contain any methanol that is present.

You should expect to collect the equivalent of approx 1L of 40% alcohol per kg of sugar used; the actual % purity will depend on the type of still you are using.

Stop collecting the distillate once you notice them containing some fusels, or if the temperature gets above about 94 ^oC (it doesn't become "dangerous" or "deadly", just that it tastes foul).

If you collect the distillate in small amounts (say 1/2 L or so), you can segregate the drinkable spirit from that with fusels in; the latter can be added to the next wash, and be collected cleanly then.

"Genuine" whiskey can be made by passing a grain wash through a pot still twice.

The alcohols in the wash begin to vaporize from the wash around specific temperatures. If by themselves they would be ...

Acetone 56.5C (134F)
Methanol (wood alcohol) 64C (147F)
Ethyl acetate 77.1C (171F)
Ethanol 78C (172F)
2-Propanol (rubbing alcohol) 82C (180F)
1-Propanol 97C (207F)
Water 100C (212F)
Butanol 116C (241F)
Amyl alcohol 137.8C (280F)
Furfural 161C (322F)

Once together, a mixture of several of them will be slightly different however. You no longer get them coming off separately, but always as a mixture. Fortunately for us though, each of the species will tend to dominate around its boiling point temperature, thus we know what's "mostly" coming off at that point. By tracking the temperature of the vapor, you have a fairly good idea when you're collecting the Ethanol your after (78-82 °C), vs. when it is starting to get lean and you're into the higher alcohols.

Note that you may also need to adjust the temperature if you are distilling at altitude - the higher above sea level you are, the lower boiling temperatures become because of the reduced air pressure.

Mark writes

Here is what I found. I'm at 7000 foot, i did a test run and water boils at 199 here. That's 93% of 212. so I cut my tables by that. Maybe this will help others. http://www.hi-tm.com/Documents/Calib-boil.html

Jack adds though ..

Actually, % of alcohol is a more reliable method of measuring cutoff points than temperature is. Thermometer placement in a still can cause a major difference in how the temp is read. Everyone's still is different- the % is more likely to give predictable results, where the temp can be off by more than 10F either high or low- giving the wrong results when duplication of another' run is being tried.

Sometimes with the tails though, even the % isn't accurate enough, with smelly tails sneaking through with little apparent notice. This is when you should also let your nose guide you - collect a few drops on the back of a spoon every so often, and check what they smell like, on a regular basis.

Filling the Boiler

When filling the boiler, make sure you leave enough headspace above the liquid, so that if it foams up a bit, that the foam won't get pushed up the column. Typically it should only be around 3/4 full.

You also want to ensure that there will be enough liquid at all times to completely cover the elements. This is particularly relevant when you've already done some "stripping" runs first, and you're now starting with something quite high in purity (e.g. 45%) and the reduction in volume will be greater.

Some washes may tend to foam up a bit & get pushed out through the column & condenser, contaminating the clean spirit. This sometimes means that for some washes you may have to leave your boiler 1/3 to 1/2 empty at times, in order to accommodate that foaming. Hogan writes about how to deal with this ...

someone was describing the use of malt extract for making whiskey and commenting that it foamed a lot in the distiller. The extract will contain a lot of proteins and when boiled it will foam a good bit. You need to let it foam as much as possible (without boiling over, of course). If you have a big pot, that helps. But you can remove the pot from heat or turn it down (if a gas heat source) let it settle a bit and fire it back up. You are looking to achieve something called hot break. The foam will soon stop rising. This process coagulates the proteins so that they are larger and will settle out, producing a clearer liquid.

Removing the Methanol

Be ruthless about tossing the first 50 mL (off a 20L wash) that you collect, as this contains any methanol (causer of hangovers - small quantities, or blindness - larger quantities). Even though I'm pretty sure I only collect less than 10mL at the methanol stage, I still discard 50mL, just to make sure. No need for penny-pinching when you're making 3L of the stuff, for less than $5. If you're using a pot still, you may need to increase this amount you toss up to 100-200 mL.

Jack writes ..I have tasted pot still alcohol that has been made both ways- when only 50ml (per 20L) was thrown out, the stuff was very sharp tasting. It became allot smoother when a full 100ml was thrown out at the start of the run.

This first portion is often called the "foreshots". They are different from the "heads". Ian Smiley (http://www.home-distilling.com/) describes foreshots as "the low boiling point compounds that come out of the still first. They contain acetone, methanol, various esters and aldehydes, and other volatiles. Foreshots are to be considered poisonous and should be discarded." Whereas heads "come out after the foreshots, and are almost pure alcohol, except that they are contaminated with trace amounts of unwanted cogeners ..." To get a really clean distinction between the foreshots and the heads, first ensure that you've let your column equilibrate under total reflux, then hold the reflux ratio high, such that you remove the foreshots only very slowly (e.g. 1 drip per second), thus allowing an equilibrium to be maintained at the top of the column, encouraging the methanol to collect there.

If you're after making pure neutral spirit for vodkas or gin you may choose to keep the heads (e.g. the next 250 mL-1L of spirits) separate from the following couple of liters (middle run) on the basis of their taste. These heads can still be used to make liqueurs, whisky, rums, etc, or redistilled later if desired totally neutral. The only problem with heads is their non-neutral taste.

The distinction between the various phases depends on what sort of still you have. They will all tend to merge from one to the other. This is particularly the case with a pot still, where you notice the temperatures always slowly changing as the distilling run progresses. Using a reflux still or fractionating column will allow the various stages to appear more distinct, as the temperature will be more stable, due to the more distinct separation of each compound.

Running the Still

For neutral spirits. there are many different ways of running a still to achieving the same results.

To get high purity, you require your column to be doing many redistillations. To get enough redistillations happening, your packing must offer sufficient "theoretical plates". The HETP that you get from packing depends on many factors, but includes the surface area, the thickness of the liquid spread out over it, and the ratio of liquid to gas. As the alcohol in the pot depletes, in order to keep the same purity, you need more redistillations happening. The usual way to do this is to improve the HETP by increasing the ratio of liquid to vapor (e.g. the reflux ratio)

As its a ratio, you can do it either by increasing the amount of liquid being returned (e.g. increase the amount of cooling water to through tubes/top condensers, or closing the off take in a Nixon-Stone ), or by reducing the amount of vapor (by reducing the power input to the boiler). Both will have the same result.

Just how much action is required depends on what the column is like to begin with. If its a tall column, packed with something with heaps of surface area (scrubbers), etc, it may already have enough redistillations happening in it to satisfactorily cope with very low alcohol input. Thus there would be no need to adjust it much during the course of the run. You'd basically turn it on, set it and leave it (though you still need to catch it right at the end).

If however the column isn't quite so great, you might need to do some serious readjusting of the reflux ratio right through the run in order to keep it doing what you desire.

Likewise, with the tall column, maybe you elect to run it heaps faster at the start (and not suffer any ill consequences), but then progressively turn it back down as things progress. E.g. - do you run it the whole run at say 10 mL/min off take, and never touch it, or say start at 50 mL/min and then slowly wind it back to 10 mL/min over the following hours.

None of these are wrong or right, just different. So when you hear of guys doing 17hr runs, that's fine if it suits them. I prefer the latter of fiddling to get the shortest time. Each to their own. With rushing, I have more "oops" happening - finding that I haven't been checking it quite routinely enough, and that its just spent the last 10-15min at too high a temp. But I'm still happy with the final taste, so that's fine for me. Others may shun my juice.

Choose for yourself - try a run at a really slow off take & little control needed, and compare against a "hands on, push it fast" approach. Maybe choose the middle ground.

Likewise as to go to electronic control or not - its just a personal choice, based on if the smoother control is worth the cost, if whether it will work for your style of operation & still design, if you dabble in that sort of thing, or if you prefer the hands on and driving.

When to Finish

This really depends on what your still is like - they can all be different. The general rule is to finish distilling when the vapor temperature near the condenser is around 92-94 ° C. Depending on how much of the "tails" you collect, your spirits will acquire a different flavor. If making a neutral spirit, you wouldn't want any tails present, so you'd finish sooner (around 82 C?), however if making a flavored spirit, you'd want a trace of them present. Note that you can always collect the tails separately from the "middle run", and redistill them at a later date to get the ethanol from them.

If your column is a very high purity one, you may in fact find yourself finishing before 82 C, with only a small amount left to collect as tails after that.

If you're doing a flavored spirit, e.g. a schnapps or whisky, often the "cut" to finish will be based on taste rather than by temperature alone.

One clue that you've gone too far is if the distillate takes on a white/milky appearance. This is because the fusels (propyls, amyls & butyls) are partially/totally insoluble with the higher %alcohols. You won't spot them if you keep your tails separate, as they are soluble within their own family in a weak ethanol solution. You may spot them though by seeing if a drop on the end of your finger gives a sun glint, and/or feels well lubricated (the old moonshiners trick). You may also see a slight film/slick on the surface of the distillate if using a clear container. If you can see them, then you can probably smell them too.

Another indication that its time to finish is when the temperature begins to fluctuate a bit. Tarvus writes :

...with my Stillmaker type reflux still, I notice that the temperature holds steady until near the end of a cut. I should note that I use a digital thermometer that registers to the nearest 1/10th of a degree Fahrenheit and refreshes itself every 10 seconds.

For example, near the end of the time the foreshots are exhausted and the ethanol begins running, the temp will fluctuate dramatically after having held rock steady until then. The same seems to happen at the end of the ethanol run. When I see the temp starting to get squirrelly, I stop the run. Maybe I leave a bit of usable ethanol in the wash, but it's worth knowing the stuff I collect is pure! :)

Let the distillate drop cleanly into the receiving vessel, so that it splashes. This will help it lose any fusels that may be present. For the same reason, it is better that the distillate is still warm to the touch, not cold. Don't put the end of the tubing under the level of the liquid, as this will cause any fusels that might be coming out as vapors to condense (and taint the flavor).

Greed is a bad thing. This is what gets your mates saying that your spirits taste "off" (you stopped noticing a while back, but everyone else still comments). You are either trying to rush things (good distillate requires time & patience), or you're wringing the neck of the beast and taking the run too far. You can't get ALL the available alcohol out of the wash. The better your still (e.g. the more "theoretical plates" / smaller HETP it has) the better your chances, but you still run the risk of contaminating your clean spirit with the tails, and having it smell & taste bad. But here's a few things to try ..

Segregate your distillate into 1L (or pint) bottles as you collect it. Work out which of them are OK, and which aren't; e.g. the first 2-3L might be fine, but you start noticing the tails in the last couple. Only keep the first ones for drinking, but put the other bottles aside. Either toss these in with the next wash as you go to distill it, or keep them from several runs, dilute 50/50 with water, and give them a run through the still on their own (see - you're not wasting it, just delaying when you get to keep it). This will allow you to really push the end of the run, as you won't be allowing it to contaminate your good drinking spirit (but don't get silly - stop when you can notice the fusels !).
Get a better still (e.g. more packing, taller column, with greater reflux) The tails won't appear until quite late in the run (e.g. may only have to put the last 0.5L aside, not the last 2-3 L).
Be patient - take the time & run the still with a higher reflux ratio (collect less, return more back down over the packing). Use more cooling water in the reflux condenser section.
The still needs to run smoothly, with even temperatures. Stop it surging - the distillate should be coming out nice & steady - either a thin dribble or separate drops. Something's wrong if its coming in spurts ; more even temperature control needed, keep the packing clean (back-flush it after every run), make sure the packing isn't too tight, have the right column size for the amount of power you're putting it (not a real skinny column with heaps of vapor going up it), don't have cool breezes blowing on the outside of the column giving spot cooling (keep the column insulated)
Take the time to polish neutral spirits well. Get a batch ahead of yourself, and always have one sitting on carbon, until you need to use it.

A 20L wash (at 12%) should produce approx 3L of 75% ethanol via a basic reflux still, or 2.3L of 95% ethanol via a fractionating reflux still.

Lots and Lots of Additional Information!!