Still Head Temperature For Making Moonshine – When To Start And Finish Collecting – Knowing when to start collecting moonshine from your still and when to finish is very important. You will often start to see some product dripping from your still when the Head / Column temperature reaches 56 Celsius.
- But generally the temperature range that you want to collect Moonshine within is between 78-82 °C and we generally stop collecting the distillate once we start getting fusels coming out.
- This is generally happens at a head temperature of 94 °C or higher.
- To Learn more about the process of Making Moonshine Head over to our page.
: Still Temperature Guide For Making Moonshine
What happens if distillation occurs too quickly?
Slow, gradual distillation essentially allows the best equilibration and heat transfer. If you heat too fast, vapors may not condense as quickly as desired, and may waste some of the column. Packing material is also crucial. High surface area packing material provides surface on which condensation can occur.
How long does the distilling process take?
In the first part of our series on Scottish pot stills we dealt comprehensively with their geometrical shape and their production, This article deals with operating the stills. Of course different distilleries operate their stills differently. Some heat fast and then distil slowly, others heat and distil fast. Glenfiddich – Still House The following chart shows the principal setup of a Scottish Malt Whisky distillery with two pot stills. Distilleries with three pot stills and triple distillation are extended by one step correspondingly. Many large distilleries have four, six or more pot stills, which aren’t operated in series but in parallel.
The connection of the pot stills can be even more complex, if for example the first distillate from several wash stills or from several production cycles is led into a single spirit still, A ratio of 3:2 or 4:3 of wash stills to spirit stills is also common. You can also triple distil with two pot stills by distilling the final product of the second distillation again in the emptied spirit still,
The chart shows a simple distillery with a wash still and a spirit still, Functional Chart of a Pot Still Distillery The principle of distillation was already known to the ancient Egyptians. Different evaporation points allow for the separation of substances by heating. The substances that evaporate first at low temperatures may be collected and separated from the rest.
- But the Egyptians used distillation only for producing perfume.
- Only in the middle ages Celtic monks discovered the production of Whisky – the water of life,
- Through alcoholic fermentation the wash ( beer ) contains approximately 8% to 10% alcohol (ethanol = ethyl alcohol).
- The alcoholic strength is determined by the yeast used and the duration of the fermentation,
When heating the wash, the substances with a lower boiling point than water evaporate with rising temperatures. The wash can’t be heated further than up to the evaporation point of the lowest-boiling substance. All heat energy is absorbed by the substance that changes its aggregate state (from liquid to vaporous), and the liquid can’t be heated further. Royal Lochnagar – Wash Still The wash still has a simple task: It is used for the first distillation of the wash, or in plain English: the beer, The capacity of the stills and the wash backs is usually coordinated.4000 US. Gal. (15,000 L) to 8000 US. Gal.
- 30,000 L) are most common.
- When hot steam is led into the heating cylinders, the wash still starts to heat the wash,
- Through the heat movement (convection) inside the still the wash is turned.
- The wash rises along the warm areas of the cylinders and sinks back along the cooler areas.
- After some 30 minutes it gets interesting: Above the heating cylinders the liquid starts to boil, and light substances (predominantly flavour -carrying esters) rise into the air above the liquid level.
The constant supply of gaseous substances leads to a slight overpressure in the still, and the gases rise into the neck of the still. But they don’t get far. The wall of the still is still too cold, and the evaporated substances condense at the wall. As time goes by more and more droplets accumulate at the wall and form bigger drops that flow back into the pot. Macallan – Inspection Window of a Wash Still That’s why wash stills have small windows in the neck, through which the bubbling wash can be watched. For if the boiling temperature of the wash is too high, liquid can get into the condenser via the lyne arm,
- This wouldn’t be so bad if the wash didn’t contain solid parts of the barley grains, which clog the thin pipes of the condensers.
- Therefore the stillman must be watchful.
- Distilleries that don’t have the time for watching the boiling put soap into the wash, which destroys the surface tension of the wash and prevents it from boiling over.
Since the soap liquefies at 122-140°F (50-60°C) and only boils at temperatures far exceeding 212°F (100°C), no soap molecules can get into the distillate. The first distillation in the wash stills takes approximately 4 to 7 hours. The wash still has a temperature of approximately 173°F (78°C), the evaporation point of ethanol. Mannochmore Low Wines & Spirit Receiver However, the low wines receiver doesn’t contain only alcohol but also all substances with a lower boiling point than alcohol, as well as some substances with a higher boiling point. They have been torn out of the molecule groups by the bubbling liquid and have been pulled into the low wines receiver together with the light alcohol molecules.
- Among these molecules is also plenty of water, which forms an azeotrope with the alcohol.
- After the first distillation the low wines typically have an alcohol content of 20% to 25%.
- After distillation the pot ale (also called spent wash ) remains in the wash still,
- It has a residual alcohol content of approximately 1%.
However, not only alcohol but also valuable proteins and minerals from the barley grains remain in the pot ale, That’s why after emptying the still the pot ale is concentrated through evaporation and sold as high-quality animal feed. Glenfarclas – Concentration System for Pot Ale Since the large pot stills only have a wall thickness of a few millimetres (ca.3/16″) they are very sensitive to overpressure and negative pressure. The worst-case scenario is therefore the collapse of a still caused by negative pressure.
When the distillation has been stopped, the pot ale is drained and the pot still cools down, negative pressure is created inside. If it becomes too high the pot still implodes with a loud bang. Since this happened more than once in the past, every pot still now has an automated pressure relief valve that keeps the pressure balance with the environment.
For filling and draining the stills, there’s another vent valve, which is usually operated simultaneously with the pumps. Fettercairn – Automated Pressure Relief Valve (Top) and Manual Vent Valve (Bottom) The table below shows the distillation balance of a wash still distillation,
|Wash||Low Wines||Spent Wash|
|Vol. % alkocol||10%||25%||1%|
The figures in the distillation balance show that the reduction of the water volume from the wash to the low wines significantly reduces the second distillation volume for the spirit still, In summary, the sole purpose of the first distillation is to reduce the liquid volume by 1/3 and to remove the solid parts of the grains that are still in the wash, Royal Lochnagar – Spirit Still The second distillation in the smaller spirit stills is carried out much more carefully and slowly. It typically takes approximately 8 hours. Since this takes double as long as the first distillation, often the result of two wash still distillations is collected in the low wines receiver and filled into the spirit still as a whole. Dallas Dhu – Pot Ale Receiver (Spent Wash Tank) & Heat Exchanger As described in the first part of this article, the spirit still has the bigger influence on the taste of the new make spirit, The second distillation is carried out much more carefully so the alcohol and the flavour substances can be separated more effectively from the water, Functional Chart of a Pot Still Distillery In the past, the so-called Worm Tubs were used to cool the spirit after distillation in the Pot Still, A Worm Tub is constructed as follows: The Lyne arm of the still is simply continued as a conduit and placed in the form of a spiral in a tub filled with cooling water,
In this way the Spirit cools down while it is passed on. However, this is a rather complex process that requires a lot of maintenance. For this reason, many distilleries no longer use this type of cooling, but prefer the so-called ‘shell and tube condensers’. These modern heat exchangers are much more space-saving and easier to handle.
In some distilleries you can still find the traditional worm tubs, for example at Lagavulin on Islay or Balmenach in the Highlands. Many do not want to do without their worm tubs despite the higher maintenance costs, as this type of cooling can also have a positive effect on the character of the distillery character,
Due to the increased copper contact and the temperature control of the water in the tub, the result is a heavier and spicier new make spirit, Since the aggressive foreshots are unwanted in the new make spirit, they are redirected in the spirit safe and not led into the spirit receiver, The functional chart from above is shown again to illustrate the function of the spirit safe,
This spirit safe has a long history and a special function. Under British law all pot stills and pipework must be padlocked. So the stillman cannot taste the spirit. Then how is he supposed to know when the foreshots have run through and the desired middle cut has started? Glenfarclas – Spirit Safe with Hydrometers and Thermometers The first thing experience teaches a stillman is the time needed to heat the still until the middle cut appears. Since thousands of gallons/litres must be heated to more than 158°F (70°C), it takes some time until the first spirit runs through the spirit safe,
- Then the foreshots run for about 20 minutes.
- In order to determine the right moment to switch the spirit flow so the middle cut can be collected, the spirit safe contains several glass boxes in which the spirit can be collected and instruments start to swim.
- If you measure the density of the spirit with a hydrometer you can determine its alcohol content with a chart.
While the foreshots are running, the alcohol content of the spirit sinks from approximately 85% to 75%. Glenfarclas – Spirit Safe with Switches for the Spirit Flow Yet this is not the only instrument that must be monitored. The density of the liquid depends heavily on its temperature. So the temperature is also measured in order to rectify the density. With density and temperature measured, the stillman can then read the alcohol content off a chart hanging next to the spirit safe.
What happens to the foreshots ? They aren’t poured away but led back into the low wines receiver. However, the foreshots aren’t enriched by this constant reflux, This is where the real magic of distillation happens. The aggressive foreshots are transformed into enjoyable aromatic substances through catalytic reactions with the copper of the spirit still.
This is a continuous process, and the quantity of foreshots remains constant in the spirit still, After the foreshots have reached the low wines receiver, the stillman changes the flow direction in the spirit safe and leads the middle cut into the spirit receiver, Aberfeldy – Spirit Receiver and Filling of Casks The distillation of the middle cut must be carried out slowly and carefully. If the spirit still is heated too much, the reflux of condensing substances with a higher boiling point at the wall of the still is prevented.
Therefore fusel oils can pass the lyne arm and get into the spirit receiver, While the middle cut is being collected, which takes approximately three hours, the alcohol content falls from 75% to 60%. But even after switching at 60% abv, the distillation continues. The fusel oils ( faints ) that appear now are led back into the low wines receiver where they are again catalytically transformed by the copper during the next distillation run.
How do we separate foreshots, heads, hearts and tails?
The distillation of the faints goes on for a long time and is only halted when a residual alcohol content of 1% is reached so no valuable alcohol is lost with the liquid remaining in the spirit still (called spent lees). You don’t often get the chance to view a low wines receiver from the inside.
It contains a milky grey-white mix of alcohol and water on which the thin, oily layer of faints swims. The distillation process is now complete. The distillation balance for the second distillation in the chart below shows the emerging quantity of new make spirit, In our example of 7925 gal. us. (30.000 L) of wash with 10% abv, the resulting quantity of 734 gal.
us. (2.780 litres) of alcohol means a yield of 92.6%.
|Low Wines||raw Whisky||Spent Lees||Faints & Foreshots|
|Vol. % alcohol||25%||67,5%||1%|
Particularly interesting in the balance are the faints and foreshots that are led back for redistillation. They increase the amount of liquid of the low wines as well as their alcohol content, Since they are a transit item appearing in every new distillation, they are neglected in the balance.
- This initially confusing fact is the reason why the alcohol content of the low wines is alternately stated between 20% and 27% in technical publications or when mentioned in a distillery,
- For the balance in our example we simply assumed an average content of 25% in the first distillation run and 67.5% in the second run.
In our example the spent lees amount to 30% of the volume of the first distillate. This is, like all the figures in the balances, just an educated guess. If you want to know more about the production of pot stills follow this link, Once the distillation is completed, the raw distillate is obtained.
- This distillate is turned into Whisky (or Whiskey ) by being matured in casks for at least three years (USA: two years).
- Just as the minimum maturation period differs in Great Britain and the USA, so does the name for the raw distillate.
- In Scotland and co it is called ‘ New Make Spirit ‘.
- In the USA the term ‘ White Dog ‘ has become established.
It is not known where the term comes from, but it was probably used by the first American settlers. ‘White’ certainly because the spirit does not take on a brown colour without cask maturation, Where the ‘dog’ comes from is not known. Some American distilleries even sell their ‘ White Dog ‘ without cask maturation or an ageing period for only a few days or weeks.
- These products are called, for example, ‘White Whiskey ‘, ‘White Lightning’ or ‘Legal Moonshine’.
- The term ‘moonshine’ contains something quite illegal per se.
- Moonshining is the illegal, domestic production and smuggling of spirits.
- As this used to take place mostly at night under the ‘moonlight’, the resulting distillate is called Moonshine.
In Europe it is not allowed to sell a spirit under the name ‘ Whisky ‘ unless it has been stored in casks for at least three years. But in the USA, many distilleries have seen a chance in selling their ‘ White Dog ‘ to make up for the revenue shortfall until they can sell the first Whiskey, which has matured for years.
What happens if you distill to dryness?
Simple distillation is a procedure by which two liquids with different boiling points can be separated. Simple distillation (the procedure outlined below) can be used effectively to separate liquids that have at least fifty degrees difference in their boiling points.
As the liquid being distilled is heated, the vapors that form will be richest in the component of the mixture that boils at the lowest temperature. Purified compounds will boil, and thus turn into vapors, over a relatively small temperature range (2 or 3°C); by carefully watching the temperature in the distillation flask, it is possible to affect a reasonably good separation.
As distillation progresses, the concentration of the lowest boiling component will steadily decrease. Eventually the temperature within the apparatus will begin to change; a pure compound is no longer being distilled. The temperature will continue to increase until the boiling point of the next-lowest-boiling compound is approached. Figure 1. Distillation apparatus. A distillation flask with a thermometer is placed in a heating mantle and is connected to a condenser. Figure 2. The tubes on the condenser are attached to a water source, with the water flowing in the low end and flowing out the high end of the condenser. The condensed vapor drips into the collection receiver.
- Check the calibration of the thermometer that is to be used. This can be accomplished by placing the thermometer in an ice bath of distilled water. After the thermometer has been allowed to reach thermal equilibrium, place it in a beaker of boiling distilled water and again allow it to reach thermal equilibrium. If the temperatures measured deviate from the expected values by more than two degrees, obtain a new thermometer and check its calibration.
- Fill the distillation flask. The flask should be no more than two thirds full because there needs to be sufficient clearance above the surface of the liquid so that when boiling commences the liquid is not propelled into the condenser, compromising the purity of the distillate. Boiling chips should be placed in the distillation flask for two reasons: they will prevent superheating of the liquid being distilled and they will cause a more controlled boil, eliminating the possibility that the liquid in the distillation flask will bump into the condenser. Figure 3. The thermometer is inserted in the distillation flask through a hole in the cork stopper. The arm of the flask is inserted through a hole in the stopper of the condenser. Make sure these stoppers are airtight, or the vapor will escape.
- Heat the distillation flask slowly until the liquid begins to boil (see Figure 4). Vapors will begin to rise through the neck of the distillation flask. As the vapors pass through the condenser, they will condense and drip into the collection receiver (see Figure 5). An appropriate rate of distillation is approximately 20 drops per minute. Distillation must occur slowly enough that all the vapors condense to liquid in the condenser. Many organic compounds are flammable and if vapors pass through the condenser without condensing, they may ignite as they come in contact with the heat source. Figure 4. The distillation flask being heated in a heating mantle. Figure 5. The collection receiver The vapors condense and drip from the condenser into the flask.
- As the distillate begins to drop from the condenser, the temperature observed on the thermometer should be changing steadily. When the temperature stabilizes, use a new receiver to collect all the drops that form over a two to three degree range of temperature. As the temperature begins to rise again, switch to a third collection container to collect the distillate that now is formed. This process should be repeated; using a new receiver any time the temperature stabilizes or begins changing, until all of the distillate has been collected in discrete fractions.
- note: All fractions of the distillate should be saved until it is shown that the desired compound has been effectively separated by distillation.
- Remove the heat source from the distillation flask before all of the liquid is vaporized. If all of the liquid is distilled away, there is a danger that peroxides, which can ignite or explode, may be present in the residue left behind. Also, when all of the liquid has evaporated, the temperature of the glass of the filtration flask will rise very rapidly, possibly igniting whatever vapors may still be present in the distillation flask.
- Never distill to dryness. The residue left in the distillation flask may contain peroxides, which could ignite or explode after all the liquid has distilled away.
- Make sure that all joints are secured very tightly. If any vapor escapes at the connection points, it may come into direct contact with the heat source and ignite.
- Never heat a closed system, the increasing pressure will cause the glass to explode. If the distillation flask has a tapered neck, the thermometer may be placed in such a way as to block to flow of vapors up the neck of the flask; in effect creating a closed system; make sure that if using a tapered neck flask, the thermometer is not resting in the lowest portion of the neck.
Simple distillation is effective only when separating a volatile liquid from a nonvolatile substance or when separating two liquids that differ in boiling point by 50 degrees or more. If the liquids comprising the mixture that is being distilled have boiling points that are closer than 50 degrees to one another, the distillate collected will be richer in the more volatile compound but not to the degree necessary for complete separation of the individual compounds.
- The basic idea behind fractional distillation is the same as simple distillation only the process is repeated many times.
- If simple distillation was performed on a mixture of liquids with similar volatilities, the resulting distillate would be more concentrated in the more volatile compound than the original mixture but it would still contain a significant amount of the higher boiling compound.
If the distillate of this simple distillation was distilled again, the resulting distillate would again be even more concentrated in the lower boiling compound, but still a portion of the distillate would be the higher boiling compound. If this process is repeated several times, a fairly pure distillate will eventually result.
- This, however, would take a very long time.
- In fractional distillation, the vapors formed from the boiling mixture rise into the fractionating column where they condense on the column’s packing.
- This condensation is tantamount to a single run of simple distillation; the condensate is more concentrated in the lower boiling compound than the mixture in the distillation flask.
As vapors continue to rise through the column, the liquid that has condensed will revaporize. Each time this occurs the resulting vapors are more and more concentrated in the more volatile substances. The length of the fractionating column and the material it is packed with impact the number of times the vapors will recondense before passing into the condenser; the number of times the column will support this is referred to as the number of theoretical plates of the column.
Since the procedures of simple distillation are so similar to those involved in fractional distillation, the apparatus that are used in the procedures are also very similar. The only difference between the equipment used in fractional distillation and that used in simple distillation is that with fractional distillation, a packed fractionating column is attached to the top of the distillation flask and beneath the condenser.
This provides the surface area on which rising vapors condense, and subsequently revaporize. The fractionating column is used to supply a temperature gradient over which the distillation can occur. In an ideal situation, the temperature in the distillation flask would be equal to the boiling point of the mixture of liquids and the temperature at the top of the fractionating column would be equal to the boiling point of the lower boiling compound; all of the lower boiling compound would be distilled away before any of the higher boiling compound.