Originally By Tony Ackland
Home Distillation of Alcohol
I'm still learning about the art of distilling - I've only been running for a couple of years now (since '97), first using a Still Spirits 20L Reflux still to knock up neutral spirits, then moving up to a "offset head" design to make it at 190 proof. I'm a Chemical Engineer by trade, with home brewing as a somewhat limited sideline hobby - a dangerous combination.
Distillation is simply the collection of the ethanol (alcohol) that was made during fermentation. It is the process of heating up the liquid so that it becomes a vapour, then condensing the vapour on a cold surface & collecting it. This works due to the fact that the vapour will contain more alcohol than the liquid it is boil off, because of the different physical properties of water and ethanol. We can then make the vapour more pure by letting it be "stripped" of its water content by passing it up through a packed column which has some condensed vapour running back down through it as liquid. When the two pass each other, the vapour will absorb alcohol from the falling liquid, and the liquid will take some of the water from the vapour. Distilling doesn't "make" the alcohol, nor turn some of it "bad", or into something that will blind you; its only collecting the alcohol that was made during fermentation.
The following pages will guide you on how to prepare the sugar feedstock, distill it, then dilute, age & flavor it. They also cover how to make a still and where to buy them.
There's two ways to go with home distillation;
See how ya go, and keep it safe.
Extended BioI first got into distilling in '97, when coming back to New Zealand to work for a few months on secondment. Heard an advert on the radio for making cheap alcohol, and thought I'd take a look (thinking it was just someone flogging food grade ethanol and essences). Got a hell of a shock to find this shop (The Brewers Barn) openly selling stills, and all the other equipment required. Was very pleasantly surprised to learn that it was absolutely legal as well. The Govt had got smart in my absence. What a golden opportunity to be able to apply my years of study to a useful & practical hobby (I'd always enjoyed the equilibrium, heat-mass transfer side of Chemical Engineering, but had ended up doing R&D work in designing, making & operating aluminium reduction cells).
The stills back then were very basic - either pot stills or basic reflux stills. I settled for a "Spirits Unlimited" 20L reflux still. I cleaned off all the markings, and sent it home in a couple of different pieces. I continued to visit NZ frequently, and became good friends with Pete, who showed me the basics of distilling; we spent many an evening trying out the new essences as they became available too. (I've since come back, and settled down in NZ permenantly).
At that point, I was eager to learn as much as I could about the subject of distilling. Unfortunately, there wasn't a lot of good information about. The commercial distilling sites tell you nothing - how they make their single malts etc is all a huge secret that they'd only mention in the broadest of terms. What information was available on the net was often downright wrong and/or dangerous. Scare tactics were prevalent - warnings like .."any alcohol collected outside of 76-82C will KILL YOU" with no basis to back them up. Suggestions to start your mash fermenting by spitting in it. There were a couple of books available, but often they were advertised with so little description, it would have been a gamble to try them. Because of the illegality of the subject, most sources dealt with distilling as some sort of counter-terrorist or moonshine hick angle.
I started with Wheeler & Willmotts "Spirits Unlimited" book. This was very comprehensive as a starting text. Every time I distilled I re-read the relevent chapters, and bit by bit it started making more sense.
I was very interested in designing a better still, but there was little information available about it, so I started going back over my Engineering books. So I started putting together a spreadsheet that would do all the calculations for me, based on first principles. That was the basis for all the calculators on this site.
As I started learning more, I began collating all my information in this website. It was orginally intended as a single page step-by-step list of instructions, but it just kept growing. Scouring the libraries for books, and finding more web sites, I slowly pieced together bits of this jigsaw, trying to seperate practical experiences and fundamental information away from misinformation.
My reflux still was only doing about 75% purity. So I began to play around with it, to try and improve it. I didn't do too much - added some more packing to it, and increased the reflux cooling. Soon it was doing 85% purity.
Not too much later, I came across the "Distillers" newsgroup at Onenet. This was a web based forum, where you could send your email question to, and all the members would recieve it too. If they knew the answer or close to it, they'd mail the reply back to the group. Wow ! This was huge. I could finally discuss distilling with like-minded interested people. The newsgroup just kept improving. It also got sold/traded a few times, and now sits with Yahoo, at www.yahoogroups.com This group has since provided me with most of the content for this site - as they've dicussed their learnings & trials & experiments, I've snipped their comments and kept them here.
In the years since, I've managed to collate quite a wee wealth of information here. None of it is rocket science, nor a black art, but rather a logical set of basics, with just a couple of twists thrown in. There aren't too many absolute truths - often there are many ways to reach the same objective, and quite often there's opposing opinions too. My idea is to provide all this for free, and to promote discussion. If its freely available, then theres no reason for anyone to do it unsafely, due to lack of knowledge or misinformation. By discussing the issues, and probing to find the answers, we can dispell many of the myths, and learn how to make a decent product in the process. Showing it as an educated, safe hobby, will be the only basis for further legalisation of it in other countries.
One of the best recommendations from the newsgroup was the "Gin & Vodka" book by John Stone & Mike Nixon. This took the still design to the next level - using a tall column, well packed, with a controlable amount of reflux happening at the very top of it. Initially I put this type of still in the category of "for puritists" - guys on the outer extremes of distilling, and didn't think it in my reach. I was more than happy with my 85% purity. How wrong ! Pete was good enough to invite me to a demonstration of the "Euro" still - a NZ copy of the Desti. That was where I got to taste some alcohol which had been distilled off at 93%. So clean ! It made such a difference to the essences. That was it. I had a local engineering firm make me up a still based on the Nixon-Stone design, and I've never looked back. 95%+ is actually incredibly easy to achieve. The still doesn't cost any more, it is far easier to run, and the quality of the spirit is awesome. I don't even bother with polishing mine with carbon anymore (very much required when 75-85% !)
Since then, I've been having a wee quest of how to improve the flavours & aging. I'm now loath to use essences, and would like to make a decent whisky all by myself. But I don't want to do it the long way. So I keep experimenting with how to cheat the flavours. I'm sure it will keep me occupied for many years - I'm far from satisfied with what I'me making at present. Not that it stops me drinking it though; need to empty the bottles to make space for the next batch !
Its proved a fantastic hobby, not only for the most productive & sayting results, but also with the many people I've met along the way. Most are only of e-mail acquantance, however I feel I've got to know them well. Some I've had the pleasure of meeting. They're from all around the globe, each with their own spin on things, learnings & experiences.
One thing I will comment/rant on though is that most of the hobby stills sold commercially are substandard. They are not designed based on an understanding of distillation, but rather are modified forms of earlier stills. Yes they do make alcohol, but often far below their true potential. One common mistake is to put cooling tubes through the lower portion of the column. You will never find an industrial distillation column built this way. Do the condensing all at the top, and strive to keep an equilibrium all the way down the column.
Don't however underestimate the fun you can have with a pot still - particularly if you want something with a bit of flavour. I have recently been privaledged to use a hand-made copper still made by David Reis (firstname.lastname@example.org) of "Destilarias Eau-de-Vie" in Portugal. More of his stills are shown in www.copper-alembic.com/
My report back to David ..
The biggest hassle was finding somewhere to set it up with enough space for the condenser. Finally worked out how to sit it on the wok-burner that's on my barbeque (see photo above). Filled the condenser with ice, and had a simple overflow out into the garden. Made up the rye-putty as you instructed - and had fun putting in on. Works really well doesn't it - that's the first time I have tried a flour dough to seal with ! The joints fit well, and its stable when full.
Last week I had started a brew off, using 1.7kg of liquid malt, about 4 cups of sugar, and made it up to 15L with water. Used just a normal beer yeast & some powdered enzyme to help convert the malt out fully. It fermented in about 4-5 days (and was a really nice beer !), and so got to settle for a couple of days.
I made a classic beginners mistake though - overfilled the alembic. I put about 7L in, thinking that would leave enough headspace for foam, but I was wrong. When it came up to the boil I got about 1L out straight away, before it settled down to the real stuff. I ended up running the 15L of beer through it in three batches - as a stripping run. I had put a small thermocouple in under the lip of the pot, and could easily measure the vapour temperature there. I collected right up to about 96C. All that stripped material I then passed through a second time. Collected about 1L at 70% strength as the main run, then switched to tails for the last 3/4L from about 88C onwards.
The main whisky smells fantastic already - a nice sweet taste to it, and it wont need much time on oak at all. I have tried making similar with my reflux still (at a low reflux ratio), but this has resulted in quite a different flavour - a lot fuller, and nicer.
Thank you again so much for the opportunity to use your alembic. Looks great, and works well too.
I'll now have to go find some suitable fruit, and see about making a calvados or schnapps in it !