After reading this post, I was wondering why have I heard of people degassing wine, but never beer? Does one also need to degas mead?

5 Answers 5


Wine is degassed because it is served still. "Still" is a term that means not-carbonated.

Beer is carbonated, so there is no need to bother, since you are introducing CO2 to the beer anyway. Mind you, there are phases of beer production on certain styles where you are essentially degassing, (diacetyl rest) but that is for different reasons than why you degas wine.

As to mead, that depends. My mead is sparkling, so I don't bother degassing it. If your mead is going to be still, then you would need to degas it.

Hope that helps.

  • Why is a D-rest like degassing? Because of the temp change and solubility limits of CO2?
    – brewchez
    May 19, 2010 at 17:10
  • My understanding is that diacetyls are volatile compounds that leave solution as a gas during the rest. I freely admit, I may be wrong about that, perhaps the diacetlys simply break down during the rest. Not sure of the right of it.
    – TinCoyote
    May 20, 2010 at 15:27
  • 1
    A diacetyl rest is not "essentially degassing." Diacetyl is consumed by the yeast, which is more active at higher temperatures.
    – Bil
    Sep 13, 2010 at 21:08
  • @brewchez: Yup. A d-rest is done after a lager's primary fermentation and before the extended lagering period. This would have the effect of increasing the beer temp from the low 50s to the mid 60s, thus forcing some CO2 out because of solubility limits.
    – DavidP
    Oct 2, 2010 at 19:11
  • DavidP is right about the solubility. The point of a D-rest has nothing to do with de-gassing, the degassing is just a side effect.
    – Frazbro
    Aug 22, 2018 at 5:40

The purpose of degassing in wine or mead is to benefit the yeast. CO2 is toxic to yeast and inhibits the yeast's ability to fully ferment the larger amount of sugars in wine/mead.

Degassing mead is highly recommended during primary fermentation to help the yeast, even if you plan on making a sparkling mead.

I'm curious about whether beer would benefit from degassing, though I suspect that yeast can handle the levels of sugar typically found in beer without needing to have CO2 removed from beer.


I don't make wine, but my understanding is that the purpose of degassing is to release the remnant CO2 still in solution at the completion of fermentation. CO2, of course, is desirable in beer, so one wouldn't want to expel that after fermentation. It's the opposite with wine.


What I have learned is that yeast when first pitched needs oxygen to grow strong and multiply, that is why it's best to introduce oxygen either by oxygen tank setup or agitation of the wort before pitching the yeast. The co2 gas emitted during the first few days of fermentation would be detrimental to health and vigor of the yeast and that is why during the first few days degassing the wort is essential for a good fermentation. .


In wine making, degassing unbinds the CO2 from proteins making it easier for the wine to clear completely after fermentation. I actually find the same is true of beer. After secondary fermentation, I use a vacuum pump to degas the beer and it's usually clear within 24 hours. Yes, I end up re-carbonating either in the bottle or keg. Some people accomplish the same thing with cider by using bentonite to bind to the proteins after fermentation.

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