Alcohol boil off during degassing?

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PSUSkier

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So I wasn't able to find a direct answer to this question so I thought I'd ask. I know you can boil off liquids under vacuum at room temperature if you apply enough of a vacuum, as well as remove the CO2 from the wine. I was curious if the Vacu Vin could generate enough of a vacuum to pull out the alcohol if one isn't careful.

I first beat the snot out of my wine with one of the drill stirrers until I didn't really see many bubbles coming up the side of the carboy. From there, I shoved one of the Vacu Vin stoppers onto a bung and proceeded to pump it out. I get a bunch of rather large bubbles rolling up the side of the carboy but I'm having trouble deciding where to stop. Do I go until I get no more bubbles or at that point will it be over-done?
 
I had my wife run some numbers for me one day and she was telling me that you could boil some off if you had a hard vacuum and a temp over 100F. I dont think that many/any of us do that. I am sure that some alcohol is removed while degassing but I am sure that some water does as well. Both are very small.
 
I know that the vacuum pumps we use for A/C systems can pull a vacuum of 29.82 inches of mercury, this is sufficent enough to boil out water in the system at any temp above 10°

One of these pumps could easily be adapted and used to generate that kind of vacuum in a carboy, but what amount of vacuum would cause it to implode?
 
A standard a/c system has a very small amount of water in it...maybe a few drops of condensation if it is left open for any amount of time.

I guess you could pull a vaccum at 30 inchs but with 5 gallons?...........it would take a LONG time to pull that much out of anything.
 
A standard a/c system has a very small amount of water in it...maybe a few drops of condensation if it is left open for any amount of time.

I guess you could pull a vaccum at 30 inchs but with 5 gallons?...........it would take a LONG time to pull that much out of anything.

It would take time for sure, but it is possible, I got the idea a while back with a few beer threads about making N/A beer, it could be done with vacuum as long as you hit the right vacuum to boil the alcohol and not the water. never bothered to try it though, a deep vacuum could certainly help degas fairly quickly I would guess.
 
Scratch that idea, doing the math, and given alcohols low boiling point, at a temp of 75°F it would only take 2.704 inches of mercury to boil off alcohol. I figured it would be higher than that.

So a deep vacuum would do more to boil off the alcohol than to simply degas.
 
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