- I have seen a few comments regarding spirit coming out with a not too pleasant taste. I have several "purists" who firstly double distil then charcoal filter several times then wood chip the spirit. OK, tastes great but then so does ours and I think the secret comes in temperature.
Most use electric stills with a thermostat controlled element that is immersed in the mash itself. We use gas. We also completely seal the still and pressurize it slightly and use a reflux head. Through experimentation we can get about 8lts of quality 80+% spirit out of 40lts of mash which is nothing more than cane sugar and molasses to produce a nice white rum flavor. No filtering or re-distilling required, just alcohol content reduction so it doesn't take your throat out! :-)
The benefit of external heating as opposed to an immersed element, and this is only my opinion, is the mash closest to the element gets too hot and the rest not hot enough. I believe the slight pressure allows the alcohol the vaporise at a lower temperature.
Oh! we also throw nothing away! (forget the methanol myth).
There is a lot of experimentation in setting the gas flame just right and the water flow through the condenser but once set right, to date not a problem.
Steve (NZ where its legal).
(Yeast: Stillmaster Ultra 8 and fermentation uncontrolled on a boat for a week)
- I've driven both gas and electric stills (no thermostats) and found a preference for electric for convenience, cost and predictability/repeatability. Gas was only more convenient for me in a location without readily available electricity.There is very little difference between gas or electric as long as the power input is the same (a rather difficult conversion to do with precision).The benefit of external heating as opposed to an immersed element, and this is only my opinion, is the mash closest to the element gets too hot and the rest not hot enough. I believe the slight pressure allows the alcohol the vaporise at a lower temperature.
Alcohol does not distill at a lower temperature in either method. The mash has a single boiling point regardless of which still you put it in. Try to run below the boiling point and your run will take a month. Try to run above the boiling point and you'll quickly realize that the laws of physics will stop you.Pressure will never make alcohol vaporise at a lower temperature. Higher pressure makes things evaporate at higher temperatures, vacuum = lower.So if it's not temperature or pressure, what is it? It might be the thermestats in the electrics. A thermostat has virtually no place in a modern still, certainly not on the heating element. (some advanced designs could use one on cooling water) Thermostats on heating elements can lead to surge boiling, where the wash boils, the element shuts off, the wash stops boiling and this cycle repeats. Cycling like that can cause a number of problems, smearing between cuts being a major one.The work around is to either disconnect the thermostat, or set it way above the boiling point so it never functions.