Question: Ifyou were to put an alcoholic beverage into a pressure cooker such as an Instant Pot and pressure cook it for a while, would that affect the alcoholic content?
Pressure cookers operate in different ways. I expect anything that maintains pressure by venting will lose some ethanol. I couldn’t tell you how much.
Modern pressure cookers have more sophisticated temperature controls and AIUI don’t vent as much, but a high ethanol content might lead to a higher pressure at a given temperature. And the seals may not be compatible. So I see some potential safety issues.
I’ve done experiments and the venting of such things appears to be from taste, a high ethanol content. From that I assume that much would be lost.
If you have one that does a minimal amount of venting (like none), then I would assume that the overall temperature at a pressure would be lower, if that pot was cooled the ethanol would re-condense and go back into solution.
I like to cook with wine in my instant pot, but i always cook a while after I’ve removed the lid, as my husband is a teetotaler. But I’ve never tested how much alcohol is left.
OP here. Background is I have a few apple trees and in late summer I picked and juiced and got about 2 gallons. I have a fermenting pot with a water seal, so let the juice ferment in there until last Friday. It looked good and on initial tasting was dry and had that alcoholic zing proclaiming adequate potency. As I drank a few short glasses however I started to worry about dying a horrible death. You know, from bacteria or some other pathogen in the mix. Then I thought I could pressure “cook” (probably more accurate to say heat under pressure) the cider, which would kill any pathogens and given that the steam is contained not boil off the alcohol. Did so. On initial tasting afterwards, the cider doesn’t have the same zing. The Instant Pot is pretty contained so I don’t think much steam was lost. Do you think the alcoholic content, assuming it was there in the first place, would have been significantly affected?
An Instant Pot is open to the air while coming up to pressure so you could lose alcohol during that time. The heating might also alter the taste.
At a guess…
We know alcohol boils at a lower temperature than water. This is how distillation works…you heat the mixture to above the boiling point of alcohol but below that of water and you get only the alcohol (mostly) vaporizing. You then collect that stuff and have a more pure alcohol.
The same will happen in your InstaPot. While the boiling temperatures change due to pressure the alcohol content should be vaporizing more than the water. Any steam that escapes should be more alcohol than water I would think. So, you will lose alcohol content from whatever is inside. Whether that is a desirable goal depends on what you are hoping for.
Missed Edit:
I should note this also depends on any vapor being released to the outside of the InstaPot. If the InstaPot is not venting vapor from inside then whatever is in there never leaves and so the alcohol content would remain the same.
How does it come up to pressure if it’s open to air?
Automatic pressure valve.
Presumably this doesn’t start venting until it’s actually achieved its target pressure; you can’t hold a pressure vessel above atmospheric pressure if its open to air.
There’s a valve in the lid that closes as pressure builds up. I looked at mine and there’s a very close fit, when the Pot is near operating pressure, there’s steam coming out at higher velocity and you can see the valve rising to fully seal the Pot.
Even cooking uncovered doesn’t get rid of nearly as much alcohol content in food as people think it does. I would imagine that pressure cooking would reduce that even more, as there’s nowhere for it to go, so rather than just evaporate, a lot of it is going to condense back into the food. Some will be lost when the pressure drops though.
Does Alcohol Burn Off from Cooking Wine? | Cooking School | Food Network
Well…I see some pressure cookers spitting steam out the top. While they retain a lot for pressure, once that pressure is reached they exhaust what is inside. So, something is being lost.
Less than an open pot? Probably. Not sure.
Certainly for my pressure cooker it’ll vent steam perhaps for a minute or two while coming up to pressure. The alcohol will vapourise first before the water boils so I guess the question is, how long is the window when the alcohol boils off but the steam pressure from the water vapour hasn’t yet closed the valve. And how much alcohol can be expelled in that window? I suspect that window is longer with a large amount of liquid and so with a modest amount of alcohol in there you might well get rid of a decent amount and approach the quantity removed by standard cooking.
Also, It might be that the alcohol is kept as vapour for longer when the venting is done at the end of the cooking period. That big whoooooooooooooost! of steam coming out of the vent may well contain another big slug of alcohol.
Or, to put it another way, I don’t know.
I am a Chemical Engineer and this problem is right up my alley. Can estimate this for you.
So consider an Alcoholic Beverage with 50% alcohol (and 50% water) - volume basis.
Say you take 2 cups (32 tablespoons) of this beverage and boil it in an instant pot for 10 mins. You will lose 2% of the beverage as vaporization.
Beverage left behind in pot = 0.98x32 = 31.36 tablespoons
Beverage evaporated = 0.02*32= 0.64 tablespoons
Liquid volume percent of ethanol in evaporate beverage = 80% (assumed a instant pot pressure of 12 psig and phase equilibria data in chemical engineering handbook).
So amount of Ethanol Evaporated = 0.64 x .8 = 0.5 tablespoons
Amount of Water Evaporated = 0.64 - 0.5 = 0.14 tablespoons
So the final composition in the beverage left behind =
Ethanol = 16 - 0.5 = 15.5 tablespoons
Water = 16 - 0.14 = 15.86 tablespoons
So the 50% by volume alcoholic beverage is now 49.4% by volume alcoholic beverage
Cite for 2% evaporation : “Instant Pot only had an average 2% evaporation during ten minutes of pressure cooking (compared to Cuisinart 4% and most stove top pressure cookers 3.5%) !” Pressure Cooker Review: Instant Pot 6-in-1 Electric – hip pressure cooking
Cite for 12 psig pressure : “. It can pressure cook a full 15 pounds per square inch, while the normal Instant Pot models will cook at 12 psi.” https://www.tasteofhome.com/article/instant-pot-max/
My wife and I visited a cidery last month. A sign in the tasting room stated all their products except one were made from pasteurized apple juice. The only product not pasteurized was the apple brandy which is made from apple wine. Next time heat the apple juice before you ferment it.
Wow! Thanks for that. So, it appears I didn’t lose much. Good 
I mentioned that the cider lost some zing by the pressure heating. I think that’s probably due to the CO2 getting pushed out.
I considered that, but was afraid it would kill the wild yeast that comprise the unique zymurgical microbiome of my three tree orchard. Next year I will do something differently, although at this point I don’t know what that’ll be.
That’s interesting, That’s a far smaller loss than I would have imagined.
That’s why we test a hypothesis, it’s good to be wrong.