How Much to Collect

of wash at % alcohol
through a still that collects its distillate at %
should result in alcohol collected
should result in water left in the boiler when finished
Note: this assumes 95% collection efficiency

Donald advises ..
    Residual tails should be cut by hydrometer in pot stills then redistilled with the next batch. Column still tails should be redistilled in process, as much as possible then pumped though an activated charcoal filer. A drinking water type filter cartrige is best, pump it through several times for vodka results. Chilling the distillate will improve filtration.

    Neutral spirits require little to no age (0-30 days). Using refined raw materials helps produce more neutral distillate and reduces tails.

    Tails are always volitle, oily and rancid. Once they come over they will dominate/spoil the flavor of the entire batch. I suggest having 3 recieving containers on the output side: center cut, orgaoliptics, heads/tails. That way if tails start on the oganoliptics the entire batch is not at risk. The danger/fun is that the organoliptic range changes with the raw material. In general tails are: Early- tequila, Armagnac, Cognac. Moderate- Brandy, Irish style (3x) whiskey, Corn whiskey, Rye whiskey, Bourbon, American whiskey. Late- Malt whiskey and distilled spirit specialties.

    Each style and flavor profile has it's own target cuts for optimun results. The cuts differ a few points between companies and account for "house flavors" & "regional traditions". The shape and composition of each still (or addition) effects the reading of cuts as well. A short pot still will give a stronger and hearty spirit with early oily tails, whereas a taller onion dome pot still will give a lighter spirit with a later tails. This means that with good hydrometers, anybody with any still, can produce the target flavor with the proper cut. Much money is spent on still improvement, before tool improvement.

    Save money by using good tools and accurate measuring equipment.
Mark has built a really neat device to allow him to monitor the alcohol purity during the course of the distillation. It floats a hydrometer in the distillate as it is received. Just remember to correct the readings for the higher temperature ....

You may be interested in something that I built so that I could monitor the quality of the output from my still. The device basically takes the output from the condenser and runs it past a hydrometer. I built this from a 6" length of 3/4 copper tube with a 1" tube flanged down and silver soldered at the top. I then connected a piece of 3/16 copper tube to the bottom of the 3/4 copper (input) and at the other end silver soldered on a funnel I then connected another piece of 3/16 copper to the 1" copper tube that collects the overflow from the 3/4 tube (Output tube). This connection was a little difficult as the 3/16 tube will not fit in between the 3/4 and 1" tube. To do this I drilled a small 1/8" hole into the side of the 1" tube and but welded it on. You could probably increase the 1" tube to 1.1/2" tube to make this easier The reason that the tube sizes are small is to ensure that the hydrometer can quickly follow any changes in output. A down side to the 3/4" tube is that if you have a high flow rate the hydrometer will give higher reading as flow of alcohol causes the hydrometer to rise. So if you are considering construction and you have high output rates you may need to increase the size of the tubes. This will of course decrease the sensitivity. I would also suggest to make sure that you hydrometer will fit inside of the 3/4" tube with some clearance for the output to flow past(My hydrometer is 1/2' diameter).

To keep aware of the temperature getting too high at any stage, theres several digital thermometers coupled with alarms available. See Brian wrote: ...
    If you get a Polder type electric thermometer they can be programmed at set temp to alarm. They also have a nice timer feature...helpful in charting your temps/time and the probe is 1/8 in Stainless which fits easily in a compression fitting at the top of the column.
When measuring the density of the distillate, you need to correct the reading for temperatures higher or lower than than which your hydrometer was designed for. Most are happy at 20C. Geoff has calculated the corrections required at different temperatures; download his Temperature correction table, an example of which is the following graph :

Jack advises ...
    Collecting spirit by temps alone is really unreliable- everyone has the thermometer set in the still in a different point- for some it could give false high readings- low for others- practice helps you figure out how to read your specific thermometer- going by the strength of the alcohol is far more reliable- and repeatable.

    Now, for the good stuff: Most pot stills that are run commercially are run until one-third of the mash volume has been collected (3 gallons of wine gets reduced down to 1 gallon of "low wines"). The second run has the spirit collected when it starts coming out of the still at 75%abv, and you stop collecting at 55%abv. The stuff that came out stronger than 75%abv is thrown out as heads. The stuff that comes out lower than 55%abv is saved as feints, and added to the next run. The feints are added to the next beer stripping run if a lighter, more neutral spirit is wanted- common in Cognac distilleries, not with whisky, though. If the feints are added to the next spirit run, the resulting spirit is a bit more flavorfull- this is how whiskey is distilled. The total spirit collected tends to average somewhere in the mid-60%abv when collected in this style.

    The 75% to 55% cutoff points are known as a "middle-third cut" among distillers, and is the industry standard for most (except Glenmorangie, which collects only from 75% to 65%abv- this is called a "middle-fifth cut").
Details from "Increasing Direct Marketing for Fruit Farmers by Connecting Producer to Producer through Research and Development of a Value-Added Product" at include some details about the cuts made when making brandy from apples:
  • each cut done by "sensory analysis" - diluting to 40% with distilled water first
  • cut from heads to heart when no longer sensed ethyl acetate present
  • cut from heart to tails when aroma changed from fruity to musty/rancid
  • no pattern for when to make the cut - varied for each different fruit, and from batch to batch. Using set amounts etc would have resulted in lower quality brandy.
  • fruits only fermented out to 5-7% alcohol
  • lower quality fruit had more heads/tails     This page last modified Tue, 20 Jan 2015 20:51:05 -0800