Degassing in a carboy....

[cmason1957]

I just can't get over that 60-90 minutes time frame. Not sure I would want to expose my wine to that pressure for that long. I think I'll stick with racking 3 or 4 times with a vacuum pump and being generous a total of 15 minutes and there is no more CO2. With appropriate levels of SO2, I don't worry about the Oxygen that may get in (and some say it's good for it to get into the wine). Each to their own.

 

[vacuumpumpman]

I was able to get ahold of Daniel Pambianchi this afternoon. I asked him some questions about boiling the alcohol while degassing with a vacuum pump.

These are his exact words- "I imagine it is possible depending on the vacuum" -from Daniel Pambianchi

So I would like to take all the MUMBO JUMBO and theories and put it to the real test -

I would take 190 (corrected from 195 ) proof grain alcohol and put it under vacuum and see if bubbles start forming, proving that it is actually boiling.

I will be using a similar A/C professional vacuum pump without any regulators as shown in the picture (post 38 )

The elevation where I will be testing is Chicago - area /Elevation = 732 feet

There is no CO2 in grain alcohol - as CO2 will only attach to water not alcohol

I would like comments regarding this test - prior to me doing it.

 

[Mrose]

My thinking would be if 195 proof PGA had 29inch of vac applied that it would boil off whatever water was left in the alcohol raising the proof. Thoughts

 

[vacuumpumpman]

My thinking would be if 195 proof PGA had 29inch of vac applied that it would boil off whatever water was left in the alcohol raising the proof. Thoughts

Alcohol boils at a lower temperature than water. So the alcohol will boil first

 

[sour_grapes]

So I would like to take all the MUMBO JUMBO and theories and put it to the real test -

I would take 195 proof grain alcohol and put it under vacuum and see if bubbles start forming, proving that it is actually boiling.

Exactly what "mumbo jumbo" do you refer to?

First of all, I believe you mean 190 proof grain alcohol. I am not aware of 195 proof being available. I am not nitpicking. There is a reason that the value is 190 proof, as you will see.

Secondly, a test of 190 proof alcohol is not at all relevant to those of us who are interested in winemaking. You need to understand the entire effing reason that the spirit you can buy at the liquor store is 190 proof. It is because that ratio is the ethanol-water azeotrope. (https://en.wikipedia.org/wiki/Azeotrope) With that ratio of ethanol to water, the exact same amount of water comes out of solution as ethanol upon heating. So, as you distill the solution, the ratio of the distillate remains the same; it is not possible to distill liquor to a higher concentration than that. Please read the Wikipedia page I referenced, and after you have understood it, submit any further questions for clarification.

You should also recognize that the elevation of Chicago is irrelevant to this question. I have explained this to you in the past. If you have lost this communication, or need a refresher, please let me know.

 

[vacuumpumpman]

Exactly what "mumbo jumbo" do you refer to?

First of all, I believe you mean 190 proof grain alcohol. I am not aware of 195 proof being available. I am not nitpicking. There is a reason that the value is 190 proof, as you will see.

Secondly, a test of 190 proof alcohol is not at all relevant to those of us who are interested in winemaking. You need to understand the entire effing reason that the spirit you can buy at the liquor store is 190 proof. It is because that ratio is the ethanol-water azeotrope. (https://en.wikipedia.org/wiki/Azeotrope) With that ratio of ethanol to water, the exact same amount of water comes out of solution as ethanol upon heating. So, as you distill the solution, the ratio of the distillate remains the same; it is not possible to distill liquor to a higher concentration than that. Please read the Wikipedia page I referenced, and after you have understood it, submit any further questions for clarification.

You should also recognize that the elevation of Chicago is irrelevant to this question. I have explained this to you in the past. If you have lost this communication, or need a refresher, please let me know.

Yes you are correct about being 190 proof instead of 195 - MY bad typo

I believe the test is to see if you are pulling bubbles out of a carboy using vacuum for 60-90 minutes = what is it ? If you remove the CO2 ( like using 190 proof everclear) and you still get bubbling action - then we can eliminate the idea of CO2 being released. CORRECT ?

 

[porkchopmessiah]

Alcohol boils at 174 f at sea level, with 28 in hg or 13.75 psi of suction it only drops to 93 degrees ....seems like a moot point since you shouldnt put that much vaccum on glass....to get boiling at room temp would seem inherently dangerous

 

[vacuumpumpman]

Alcohol boils at 174 f at sea level, with 28 in hg or 13.75 psi of suction it only drops to 93 degrees ....seems like a moot point since you shouldnt put that much vaccum on glass....to get boiling at room temp would seem inherently dangerous

I agree ^ that you do not have to put that much vacuum on glass to remove the CO2 -

This is exactly the point I would like to make -

I did find that there are lower boiling points in wine other than Ethanol - which would start to bubble first =

• Acetone – 56.5C (134F)
• Methanol (wood alcohol) – 64C (147F)
• Ethyl acetate – 77.1C (171F)
• Ethanol – 78C (172F)

 

[sour_grapes]

I am not sure where the idea that ethanol does not dissolve CO2 is coming from. Ethanol can dissolve about 3 times as much CO2 as water can.

But back to thinking about the liquids: Again, you can evaporate a liquid without boiling it. So, yes, I agree that if you remove the partial pressure of water and/or alcohol in the headspace, you will evaporate water and/or alcohol from your wine. Again, this could be done with a vacuum pump, or it could be done by leaving a glass of wine on your kitchen counter on a warm, dry day. You don't need to see a bubble for evaporation to happen.

Now, let's think about what it should mean if you DO see a bubble. Does that mean it is alcohol? No, it doesn't. Let's do a thought experiment. Imagine you have a bottle of pure ethanol, and you are drawing a vacuum on it, but you are at a pressure/temperature combination that is below the boiling point. The atmosphere (i.e., the headspace) will be full of ethanol vapor. Now, let's say an omnipotent being freezes time, goes into the bottle, and injects a bubble of pure ethanol vapor, then restarts time. What will happen to that bubble? Answer: it will collapse, and the vapor will re-condense into the liquid phase. It will not rise up to the surface. The vapor pressure of the ethanol inside the bubble is not high enough to withstand the pressure that the liquid exerts on it, so it collapses. (The definition of boiling is when the vapor pressure is high enough that the bubble does not collapse.)

So, in the real world, if you see a bubble during degassing (and you are not boiling the whole vessel) it is not a bubble of alcohol. It was some dissolved gas coming out of solution.

 

[vacuumpumpman]

Paul - so does 190 proof ever clear (bought from the store ) have CO2 in it ?

 

[Johnd]

Steve, if you really want to know if you can vacuum alcohol out of wine, then set up a test on a real wine. Take a sample out of a carboy and label it as the original sample. Vacuum the carboy for 5 minutes, take a sample and label it accordingly. Continue down that path maybe with a half hour vacuum sample, a one hour vacuum sample, 2 hours, whatever.

When you're done collecting all of the various timed vacuum samples, send the samples off to an appropriate testing facility to have the alcohol content analyzed, then you can know.

 

[vacuumpumpman]

Thank you Johnd. For a simple solution.

I did not want to go down that route because it might be referred as distilling and I know that it is not allowed on this forum.

I only wanted to prove that taking full vacuum on a carboy for 60 -90 minutes. That you are not still removing CO2 from the wine.

So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?

 

[porkchopmessiah]

Couldn't you just float the hydrometer I the carboy and forget abou the lab, watching specific gravity climb higher after bottoming out after fermentation as alcohol is being removed? It would get back to 1.00 eventually right? Assuming your dealing with wine...in your everclear scenario (even with wine) you should start to see a decent amount of change in volume as you start remove parts of the solution.
Yes? No? Maybe?

 

[sour_grapes]

Paul - so does 190 proof ever clear (bought from the store ) have CO2 in it ?

I don't know. I would imagine it would have at least 0.04% (like the atmosphere does).

 

[vacuumpumpman]

I don't know. I would imagine it would have at least 0.04% (like the atmosphere does).

Thank you ,

So if I took vacuum to it - I will probably not pull much if any co2 from it - correct ?

I wonder what the percentage of co2 in young wine that not has been degassed of the CO2

 

[sour_grapes]

I only wanted to prove that taking full vacuum on a carboy for 60 -90 minutes. That you are not still removing CO2 from the wine.

So the real question would be - how would you know when you have removed the CO2 from your wine using this method and not transferring under vacuum ?

When I first started playing with vacuum degassing, I pumped on my carboys for a long time. I kept seeing bubbles. I used a half-filled carboy so that I could slosh the liquid around, each slosh causing more bubbling. I was disappointed, as this seemed to go on forever (~30 minutes). My vacuum pump has an outlet hose, so I decided to "sample" the gas coming off. The gas coming off was acrid and biting -- CO2, I am pretty sure.

HOWEVER, there wasn't much of it. It took me an embarrassingly long hour or so to realize that the bubbles did not contain much gas. Although a bubble might be the size of a pea or a marble or so, I was at such a low pressure that there was not much actual stuff in the bubble.

 

[Swedeman]

It is well documented that low fermentation temperature, due to less vigorous fermentation, preserve wine flavor as less volatile compounds is lost. Applying vacuum seems less attractive to me for the very same reason, any thoughts on that?

"First of all, I believe you mean 190 proof grain alcohol. I am not aware of 195 proof being available"
FWIW, even 200 proof is available https://us.vwr.com/store/product/16763162/ethanol-anhydrous-99-9-200-proof

 

[vacuumpumpman]

It is well documented that low fermentation temperature, due to less vigorous fermentation, preserve wine flavor as less volatile compounds is lost. Applying vacuum seems less attractive to me for the very same reason, any thoughts on that?

"First of all, I believe you mean 190 proof grain alcohol. I am not aware of 195 proof being available"
FWIW, even 200 proof is available https://us.vwr.com/store/product/16763162/ethanol-anhydrous-99-9-200-proof

Thanks for the correction as I stated above that it was a typo - referring to the 190 proof - I will correct it now

I agree that taking straight vacuum on a vessel is probably not good for the wine.

But this is how we learn - by actual examples and field testing.

 

[sour_grapes]

"First of all, I believe you mean 190 proof grain alcohol. I am not aware of 195 proof being available"
FWIW, even 200 proof is available https://us.vwr.com/store/product/16763162/ethanol-anhydrous-99-9-200-proof

Obviously. I meant you cannot get potable alcohol to higher than 190 proof via distillation.

 

[sour_grapes]

But this is how we learn - by actual examples and field testing.

Yes. Or by reading about the accounts of others who did careful field testing. (Sometimes known by the nickname "experiments.")