First foray into distillation...don't think it went well

[Ty520]

So I just bought an air still to experiment with distilling some of my wines and meads - I know it isn't an optimal rig, but it fits my budget, production and storage capacities for the time being; didn't want to sink a bunch of money into another hobby if it ends up going sideways. the good thing is that unlike some of the older air stills, it at least has control over the kettle temp.

After some talks with some more experienced distillers who have used an air still for micro experiments, I finally decided i needed to pull the trigger, fermented 1 gallon of cherry wine, and ran a stripping run. I was instructed to do it "fast and hot, and not make any cuts."

I began with the kettle set to 94*C (for note, i am at 2500 ft altitude). from the get-go, it emitted an unpleasant odor i can only describe as "fake butter." During research, this descriptor came up multiple times, so I wasn't completely worried.

Eventually, the flow began to slow down, and throughout the course of the run i gradually had to bump the temp up to maintain a flow of about 1 drip a second, finishing out at 98*C.

During the back end of distillation, though, it started to emit a smell I can only describe as "BBQ" - like that smell that lingers on your hands long after hitting up a BBQ joint

My assumption is that I ran it too hot? That being said, when I cleaned out the dregs, there was no signs of scorching/burning. so although it remains my lead hypothesis, I cannot be certain one way or another.

Another thought is that maybe it could have something to do with my wine base being composed of tart cherry, which is prefered in mead making...but perhaps too tart to maintain fresh, fruity aromas and flavors in a distillate?

 

[kmmuellr]

No clue, as I've never gotten a BBQ flavor. However, I don't think you ran to "hot", as the liquid will boil at whatever temp that it is going to boil at. When I strip, I run at over 3/4 power from my 5500W element. The temperature changes as the volatiles and alcohols boil off. More power gets me a faster boil off, but not a hotter boil. FWIW, I don't have a thermometer on my rig. I adjust power to the still based on how fast the heat is rising in my column (while heating up) and how fast I'm flowing. While stripping I have a continuous flow, think a thick pencil lead; for a spirit run I'm at a "drip, drip, spurt" to a full flow, thin pencil lead.

Having never run an airstill, I don't know, but from what I've read its no different than a bigger rig. Run some more and collect, then run a slower stripping run, and collect a lot of little jars for cuts.

K

 

[Ty520]

Right, I get that each liquid evaporates when it evaporates, but it isn't purely just liquids in the wash - the wine is full of particulate matter, so couldn't that be "cooking" during the boil and giving off some funky aromas and flavors that transfer into the distillate?

It seems that whenever I read about distilling Brandies in particular, professionals advocate going much lower and slower than other distillate types, always emphasizing " slower is better"...like "1 drop every 3 seconds" slow

After all, regulating power is just another form of measuring temperature, as temperature is just a measure of energy input. No?

Otherwise what reason would there be to alter power input at all? And not Just go balls to the wall 100% all the time?

 

[kmmuellr]

Good questions!!

Right, I get that each liquid evaporates when it evaporates, but it isn't purely just liquids in the wash - the wine is full of particulate matter, so couldn't that be "cooking" during the boil and giving off some funky aromas and flavors that transfer into the distillate?

Potentially. I've only done one "brandy" and that was with finished wine that I had laying around. One other mead went through the still as well, but that was also a well finished wine, so no particulates. I don't have any experience for this one, sorry!

After all, regulating power is just another form of measuring temperature, as temperature is just a measure of energy input. No?
Otherwise what reason would there be to alter power input at all? And not Just go balls to the wall 100% all the time?

Temperature is NOT a measure of energy input. Think of a hard boil of water and a simmering of water when you're cooking. Both are at 212 degrees, but they are clearly at two different levels of "energy input".
Why alter power input? To get different results. At a strong, rolling boil you're getting more "stuff" being entrained along with the vapor that you're expecting. ie, water will evaporate if sitting in a pan on your kitchen table. Its not boiling, but there is energy in the system that is allowing that evaporation. Add heat and it goes faster. So, during your low energy boil, your still bringing along compounds that are not at their boiling point.

Make sense?

K

 

[Ty520]

I think we're in agreement, but saying it differently? or possibly talking about two different things?

however it seems we are agreement that the intensity of the boil will alter the aromas and flavors of the distillate by affecting the esthers and polyphenols of the particulates in the wash since those particulates never leave the kettle and are going through dramatic temperature swings. Especially since just the fermentation stage temps can radically alter the aromas and flavors of a wine.

although i do disagree about the energy and temp not being equivalent, as increasing temperature is a factor of energy input in Joules, and amperage is a a factor of watts and voltage, and watts are Joules as a factor of time. so we're just monitoring the intensity of our boils via different metrics

 

[Homebrew Harry]

So I just bought an air still to experiment with distilling some of my wines and meads - I know it isn't an optimal rig, but it fits my budget, production and storage capacities for the time being; didn't want to sink a bunch of money into another hobby if it ends up going sideways. the good thing is that unlike some of the older air stills, it at least has control over the kettle temp.

After some talks with some more experienced distillers who have used an air still for micro experiments, I finally decided i needed to pull the trigger, fermented 1 gallon of cherry wine, and ran a stripping run. I was instructed to do it "fast and hot, and not make any cuts."

I began with the kettle set to 94*C (for note, i am at 2500 ft altitude). from the get-go, it emitted an unpleasant odor i can only describe as "fake butter." During research, this descriptor came up multiple times, so I wasn't completely worried.

Eventually, the flow began to slow down, and throughout the course of the run i gradually had to bump the temp up to maintain a flow of about 1 drip a second, finishing out at 98*C.

During the back end of distillation, though, it started to emit a smell I can only describe as "BBQ" - like that smell that lingers on your hands long after hitting up a BBQ joint

My assumption is that I ran it too hot? That being said, when I cleaned out the dregs, there was no signs of scorching/burning. so although it remains my lead hypothesis, I cannot be certain one way or another.

Another thought is that maybe it could have something to do with my wine base being composed of tart cherry, which is prefered in mead making...but perhaps too tart to maintain fresh, fruity aromas and flavors in a distillate?

I bought one in great shape at a sale for 8 bucks. I heard that being sold as water distillers they had a small hole in the condensor to allow chlorine to escape. I also read that these put off a bad odor when distilling anything else. I took mine apart and sure enough mine had the hole. I clamped it off with a piece of silicone. I would try to run it lower if I were you. Good luck.

 

[Ty520]

I bought one in great shape at a sale for 8 bucks. I heard that being sold as water distillers they had a small hole in the condensor to allow chlorine to escape. I also read that these put off a bad odor when distilling anything else. I took mine apart and sure enough mine had the hole. I clamped it off with a piece of silicone. I would try to run it lower if I were you. Good luck.View attachment 763884View attachment 763885

Interesting - mine was advertised as specifically being appropriate for alcohol distillation, but I'll have to check for this hole. doesn't make sense to me as to why the gas wouldn't justt escape at the end of the nozzle, but... ¯\_(ツ)_/¯

definitely going to run at a lower temp next round

 

[Windy City]

You can't properly run a still off of temperature control. A stills heat input needs to be run off of power control. The two are not interchangeable.
My boiler may be at 202F a quarter of the way through the run but turning power up or down will not change the temperature just the output.
A great and fast read on this; Zymurgy Bob's Magic Boiling Myth

 

[Ty520]

You can't properly run a still off of temperature control. A stills heat input needs to be run off of power control. The two are not interchangeable.
My boiler may be at 202F a quarter of the way through the run but turning power up or down will not change the temperature just the output.
A great and fast read on this; Zymurgy Bob's Magic Boiling Myth

Yeah , I get that and keep getting bombarded with that link by moonshiners

...and then they go on to prove they don't understand anything about using wine or using it as a wash - as proven by the "experienced" guy who told me to just crank it to max becasue its "just sugar and water"

a wine isn't just alcohols and water - it is full of particulates that stay in the wash through the entire run, and can throw completely different flavors and aromas at just a 20 degree change.

These are the things actually imparting the finer nuanced flavors in wine and liquor made from something more than just water and sugar.

It seems most of these guys don't do brandy, because when it comes down to the nuances and finesse of composing the actual wine to use as a wash, their eyes glaze over and they just start giving guesses as ignorant as my knowledge of distillation.

 

[Windy City]

I understand particulate, I distill on the grain at 2.5 pounds per gallon on average. Doesn’t get much more particulate than that.
As far as someone telling you to crank it up, you don’t have power input control on that unit so anytime the element is on its on all the way.
Trying to overcome poor equipment with trying to play with temps will not get you the best outcome.
Again you have no control of what temp your wash will boil at while distilling.
Also recommend doing three stripping runs and then take all that and do a spirit run you will get much better results
Don’t forget to collect in small jars and do proper cuts
Hope this helps

 

[doug293cz]

...

a wine isn't just alcohols and water - it is full of particulates that stay in the wash through the entire run, and can throw completely different flavors and aromas at just a 20 degree change.

...

Except that you cannot change the temp of the liquid while you are distilling. If the liquid isn't boiling, you won't get enough vapor to collect any condensate. Once it is boiling, the temp is determined only by the liquid composition, and local atmospheric pressure. Adding more heat (energy) will increase the boil vigor, increasing the rate of vapor generation, but will not affect the temperature.

Brew on

 

[bracconiere]

Adding more heat (energy) will increase the boil vigor, increasing the rate of vapor generation, but will not affect the temperature.

more vigorus boil, will increase head temp though....might be something to keep in mind if you're just using air cooling for a condenser?

 

[bracconiere]

oh and this is kinda off topic, but. i think for small batches like this it will come in handy for keeping track, and regulating boil vigor...

https://www.ebay.com/itm/153572164024?hash=item23c19d41b8:g:VyYAAOSwVJFd8fIB

 

[Windy City]

More vigorous boiling will not change the head temp. The quantity of alcohol to water is what determines the head temp. The air still is basically a pot still, there is no forced reflux over a column of structured packing.

 

[bracconiere]

More vigorous boiling will not change the head temp. The quantity of alcohol to water is what determines the head temp. The air still is basically a pot still, there is no forced reflux over a column of structured packing.

not what my thermometer tells me? when the top of my still starts getting to around 90c, i back off the heat until it drops back down to 80-85c....

 

[bracconiere]

which reminds the first post said you raised the temp? i always start full bore then as the alcohol comes over and there's less in the kettle, i back off the heat? the run off slows down, but doesn't stop...

 

[doug293cz]

More vigorous boiling will not change the head temp. The quantity of alcohol to water is what determines the head temp. The air still is basically a pot still, there is no forced reflux over a column of structured packing.

Yes it will. There is a thermal gradient set up between the outlet end of the condenser and the surface of the boiling liquid. Heat is lost from the surfaces of the equipment and into the cooling fluid of the condenser. More vapor coming from the liquid, carries more heat to the top of the still and entrance end of the condenser, thus causing it to heat up, and increase the thermal gradient (and heat losses to the environment from the equipment surfaces.) Eventually you reach a quasi-equilibrium, and stable thermal gradient if you have constant heat input to the liquid, constant coolant flow, and constant coolant inlet temp. Putting more heat into the liquid will shift this equilibrium towards higher temps.

Brew on

 

[bwible]

Lots of reading material out there, distiller’s talk forums, etc. Yes, temp is a big deal. Water boils at 212F. Ethanol boils at 173. So no, there is no reason to run anything “full boil.” It does make a difference in flavor and more heat is not necessarily better.

 

[doug293cz]

Lots of reading material out there, distiller’s talk forums, etc. Yes, temp is a big deal. Water boils at 212F. Ethanol boils at 173. So no, there is no reason to run anything “full boil.” It does make a difference in flavor and more heat is not necessarily better.

What do you mean by "full boil"?

Brew on

 

[Windy City]

I agree with what you are saying Doug but my point is that during pot stilling we don’t “control “ the temperature. During your run it may start producing around 198F ( depending on ABV of boiler charge) but will keep climbing through the whole distillation. As you remove more alcohol from your boiler your boil temperature point keeps rising. More heat input only makes it happen faster. I don’t care what wash, must or mash you are stripping there are no real advantages to running a pot still by drips and could actually make it worse through mallardization. A pot still is not a reflux still and a air still is a pot still.

 

[rnorman57]

Lots of reading material out there, distiller’s talk forums, etc. Yes, temp is a big deal. Water boils at 212F. Ethanol boils at 173. So no, there is no reason to run anything “full boil.” It does make a difference in flavor and more heat is not necessarily better.

And a water/ethanol mixture will boil at a temperature in between 212 and 173, which is only determined by the ratio of water and ethanol

 

[bracconiere]

which is only determined by the ratio of water and ethanol

i'd imagine sugar, and other stuff would effect it also?

 

[doug293cz]

I agree with what you are saying Doug but my point is that during pot stilling we don’t “control “ the temperature. During your run it may start producing around 198F ( depending on ABV of boiler charge) but will keep climbing through the whole distillation. As you remove more alcohol from your boiler your boil temperature point keeps rising. More heat input only makes it happen faster. I don’t care what wash, must or mash you are stripping there are no real advantages to running a pot still by drips and could actually make it worse through mallardization. A pot still is not a reflux still and a air still is a pot still.

You are correct that we cannot control the temperature of the boiling liquid, but we can control the heat input, which will change the rate of evaporation. A higher rate of evaporation will send more vapor, and more heat, to the top of the cap, which will make the top area hotter. The hotter the vapor at the top of the cap, the less alcohol it contains. The heating effect of more vapor can be mitigated by increasing the cooling water flow in the condenser (cann't be done in an air [cooled condenser] still.)

Brew on

 

[bracconiere]

The heating effect of more vapor can be mitigated by increasing the cooling water flow in the condenser (cann't be done in an air [cooled condenser] still.)

could always use a stronger fan?

and another OT thought for @Ty520 i'd short that distiller to by pass all IT'S temp control and use something like this,

https://www.amazon.com/munirater-Va...tt+fan+speed+controller&qid=1648587375&sr=8-2
and this, kinda as a visual "looking at the flame" thingy....

Edit: Oh, and your two links are the same. Given the context, I expected them to be different.

edit: sorry! it's meant to be a kill-a-watt meter, so that when your dialing the dial on controller you can get real time feed back of watts being used...

https://www.amazon.com/P3-P4400-Ele...4c68&pd_rd_wg=JJy3w&ref_=pd_gw_ci_mcx_mi&th=1
(for some reason i always think just looking at the page always put the link into my clip board...

@doug293cz and not to hijack, but i've those fan speed controllers aren't the best for hot plates, but it's working great for me many a time. so if this is bad advice let both us know....

 

[doug293cz]

could always use a stronger fan?

and another OT thought for @Ty520 i'd short that distiller to by pass all IT'S temp control and use something like this,

https://www.amazon.com/munirater-Va...tt+fan+speed+controller&qid=1648587375&sr=8-2
and this, kinda as a visual "looking at the flame" thingy....

https://www.amazon.com/munirater-Va...tt+fan+speed+controller&qid=1648587375&sr=8-2
@doug293cz and not to hijack, but i've those fan speed controllers aren't the best for hot plates, but it's working great for me many a time. so if this is bad advice let both us know....

Yeah, a variable speed fan on an air still will work the same way as varying water flow in a typical condenser. I was assuming that the integrated air stills have a fixed speed fan.

Edit: Oh, and your two links are the same. Given the context, I expected them to be different.

Brew on

 

[bracconiere]

and the reason, i recomend the fan speed controller, is it's a constant heat. not the cycling type that the air still probably uses....

when i use that combo with my 1500 watt plate. i can vary the wattage it uses from ~400 to the 1500(1200 actually) and when it starts getting rough coming out the condenser, i find lowering the heat works A LOT better then running my head cooling that is before the vapor reaches the condenser....better bellow then at the top in my experience?

 

[doug293cz]

i'd imagine sugar, and other stuff would effect it also?

Yes, solids (and non-volatile liquids) dissolved in water raise the boiling point a little - it's known as "Boiling Point Elevation." We can use the equation from the link to estimate the boiling point elevation for 20 wt% maltose (or sucrose) in water.

𝚫Tb = Kb * bsolute * i, where:​

Kb = 0.512 for water​

bsolute = molality of sugar​

i = 1 for sugar​

​

Molality is the moles of solute in 1kg of solvent. 20 Wt% sugar means the solution is 80% water and 20% sugar. If we have 1 kg of water, we have 1.0 / 0.8 = 1.25 kg of solution, and this contains 0.25 kg of sugar. Maltose (and sucrose) have a molecular wt of 0.3423 kg/mol, so the molality of the 20% solution is 0.25 / 0.3423 = 0.73. So, the boiling point elevation would be:

𝚫Tb = 0.512 * 0.73 * 1 = 0.374°C = 0.673°F​

​

As you can see, the effect is small even for fairly concentrated solutions.

Brew on

​