Originally By Tony Ackland
Double Distilling for Whiskey etcHere we try to replicate the traditional style as used in commercial distilleries world wide. See Making Whiskey - A Personal Experience by Roger Dowker for a detailed description of the commercial process, including when the various cut-off points are.
The trick to this appears to be the stuff legends are made of, and closely guarded by those who know. It's the matter of how much of the first condensate, or foreshots, to discard and how much of the middle cut to keep before discarding the last runnings, or feints.
Steve writes that its difficult to do this by temperature alone, nor to have a single set of guidelines ...
For the various %'s at which to do the "cut", Donald advises to use a great hydrometer with 0.5% or greater calibrations for best results, and suggests ...
When about 2/3 - 3/4 of the way through the middle run, and approaching these cut points, start collecting the spirits in smaller collection containers, and smell each of them seperately. The flavour will change from that of the neutral spirit, to more and more of the flavour coming through. This will intensify, but then start to become bitter. You need to work out when to make your "cut" during this period, but do so before it gets to the bitter stage. After making the cut, keep collecting (seperately) the feints up to about 92 °C, and add these to future runs.
For a reasonable whisky without the long term maturation try this :
Load the still with the low wines and set it going.
You can now take the 5 litres, flavour it a little bit, put it in a small keg or flavour it with some oak essence. If kegging cut with water to around 40% or the angel's share will get too much. Don't charcoal filter or polish this spirit, as all the tasty bits you've just worked so hard to obtain will go too.
In theory, lets say I was the distiller at Ardberg with one wash still and one spirit still, I would run all the spirit out of the washstill as low wines, load this into the spirit still and run foreshots, high wines, with a cut at betwixt 65/60% then the rest as feints down to X %. The feints could then go back to the wash still or spirit still for the next batch. If I were at Ardberg, I would probably run them back to the wash still.
In order to get congeners, as opposed to a neutral profile it is important not to have a definitive reflux device in the steam path - enough refluxing will occur within the headroom, the "roof" of the still body, the lyne arm or equivalent. Make sure the still is only filled to about the three quarter mark.
As the weather becomes hotter and hotter in the southern hemisphere pot distillers put less wash in the body of the vessel thereby allowing more head for particulates of the solid variety to not be entrained [carried over] into the distillate. If you have variable control throttle back a bit.
Jack adds regarding the tossing of heads...
I also learned that these "middle cut" numbers are good for any volume, and any still- I have made a corn whiskey and have "made the cut" according to Ian Smiley's numbers- but I did this with an ice-water-wok still, and only 2-liters of freeze-concentrated mash (equal to 4 liters unfrozen). It comes out to:
all adding up to the 750ml bottle I normally get of pretty rough stuff out of this still. Just by applying the middle cut numbers, I get just over half as much- but it is a LOT better.
By the way, even the Scotch distilleries are now admitting that yeast strain makes a difference in the spirits' final flavor. They figured this out after a couple of research chemists at a distillery made a batch, then filtered ALL the yeast out, and distilled it. After comparing the resulting spirit with regular (unfiltered mash) spirit, they found (under liquid chromatography), that the yeast has a BIG influence on flavor due to the long chain fatty acid esters that are found in yeast do distill over into the spirit- this is, in fact, the cause of cloudiness in spirit thats been run through a potstill only once, not the heavy alcohols as was once thought.