How To Degas Wine Correctly

by Kelvin Teo | Last Updated: May 3, 2021

Whether you’re a home winemaker crafting a few bottles once in a while or a dedicated enthusiast producing several cases a year, you know the tiniest details matter. Winemaking is a complex matter, and to think crushing the grapes and letting the juice ferment is enough would be a huge understatement.

Even the most unconventional winemakers with the strictest hands-off approach know there’s something to be done every step of the way, from grape to bottle. That if you want the best results, and of course you do!

One of these steps is degassing wine, one of the final but most important steps in the wine making process necessary for red, white, and even sparkling wine.

So, what’s the deal with degassing wine? Should you try it? How does it help? Well, let’s cover the topic thoroughly and answer the most common questions about it. Here’s all you need about degassing wine. It’s actually less complicated than it sounds!

What is Degassing Wine?

If you’ve tried homemade wine before, you might have experienced that the wine is fizzy. It often has a sparkly sensation. That’s carbon dioxide (CO2), the remnant gas caused by your winemaking yeast. You might have also spotted cloudy wines that just lack that brightness, even if they’ve been clarified — that’s the CO2 as well.

The suspended carbon dioxide gas can reduce your wine’s looks, quality and stability, so you have to remove it someway. Interestingly, this is less of a problem in beer or cider, but it’s very important for wine, especially if it doesn’t spend a lot of time in a barrel.

Barrel-aging adds flavor and aromas to the wine, and it helps it mature, but it also helps to get rid of the carbonic gas in a natural exchange with the environment. It comes as no surprise that white wine, which nowadays is often bottled without barrel aging, has this problem more than reds.

We should clarify that degassing wine is not an essential task in all cases, but it can make the difference and turn a good wine into a great one. In a competitive market such as this one, even if you’re just making wine to share with your pals, you should do anything in your power to get the best results.

Why Degassing Wine is Important?

Degassing wine is important for aesthetic, textural, and safety reasons. Excessive suspended gas in wine is one of the most common faults for the uninitiated. The fact that the process used get rid of excess CO2 is so easy yet often skipped by home winemaking enthusiasts is worrying.

If you don’t degas wine, three things can happen. First, suspended CO2 in your wine will not allow the clarifying and fining agents to do their job properly, as the suspended bubbles will prevent solids from precipitating. This will lead, in the worst-case scenario, to murky wine. That bright, clean look you’re after can only be accomplished if you degas your wine.

Second, we have the bottles themselves. You’ll probably not end up with sparkling wine, but it will have a fizzy texture, and that’s not what you’re looking for. Once bottled, the trapped bubbles can also push the cork, ruining your entire production. Even the sightliest cork movement will allow oxygen to find its way inside the bottle and oxidize your wine.

Lastly, carbonic gas is perceived as acidic in the palate which can unbalance the wine massively. Wine is sour enough already, and with too much gas, it can be less than pleasing. Once you bottle the wine, there’s no going back, so make every step count.

The good news? Removing excess gas in your wine is easy, and there are several ways of achieving it. You’ll find it easy to incorporate these practices into your winemaking, and the results will be better than ever.

Note: Sparkling wine should also be degassed before you gasify it, whether it’s by way of a secondary fermentation in a tank or bottle; or by applying artificial carbonation.

When is it Time To Degas and What Happens When You Don’t?

Always degas your wine after malolactic fermentation — not before. Despite what some people might say, your wine should stay mostly undisturbed throughout the fermentation process. Some batches foam more than others, but you should ignore that. During fermentation, just pay attention to your alcohol/sugar levels and let the yeast do its work.

Never degas a wine without removing the lees or spent yeast first either, especially if you’re using the ‘agitate’ method. Yeast, even when dead, has the power to change your wine’s profile if provoked because of the enzymes still in them. After racking your wine and allowing the malo to occur, then it’s time to degas it if needed or when in doubt.

How to know if you need to degas your wine? Well, with some experience under your belt, you’ll recognize the problem immediately by looking at the wine’s clarity and by tasting it regularly.

If you’re new to winemaking, then first make sure the primary fermentation has ended, and monitor your acidity levels to control your malolactic fermentation, if any. Only when both processes are finished, should you measure the amount of gas in the wine, always before clarifying and fining it.

Failing to do so will result in a cloudy wine with too much acidity and an odd mouthfeel. You can also have issues after bottling, and all this adds up. It’s your reputation on the line, so pay special attention to the amount of gas in the liquid in the same way you monitor phenolic, acid and sugar levels.

If you detect too much dissolved gas, then follow the instructions below. When in doubt, also degas the wine. The good thing is you can’t overdo this process.

3 Effective Ways To Degas Wine

1. Degassing Wine Naturally

For degassing, everything is in our favor. Diluted gas eventually finds its way out, so all you have to do is let your wine rest. This is particularly true inside wine barrels, which are porous and allow small amounts of gas exchange.

Big wineries rely on this method because most red wines spend a few months in cask. White wines, though, more often than not fermented in stainless steel tanks and spending no time in cask, need to be degassed always just before clarifying and pumping it into the bottles.

Raking the wine during its maturation period in barrel, a customary practice that removes solids, takes care of the suspended gas as well. That’s why this one is called the natural method.

2. Agitating Method

If you’re not planning on aging your wine in an oak barrel, then you’ll have to eliminate the gas bubbles yourself. There are specialized degassing rods that are no more than a tool to swirl your wine. They not that inexpensive, but technically, you can use anything to stir your wine as long as it’s sterilized.

Swirl your wine to create a whirlpool, do this for about ten minutes and then close your container with an airlock. Let it rest. Repeat the process for between 5 or 7 days until you see there are no more bubbles. Make sure your wine is never exposed to oxygen and try not to make a splash; you should release the gas bubbles without disturbing the wine too much.

Here’s a video to help you visualise the process better:

3. Using a Vacuum

Using specialized equipment, you can create a vacuum inside your carboy, effectively leaching out all the carbonic gas in one session. The negative pressure created inside the container forces any bubble to surface.

There are a few downsides to this process, though. For starters, this is specialized equipment, and it can be expensive, and considering you can achieve similar results with a stick is something to think about.

Your vacuum pump might not be strong enough to cause the gas in the wine to be released, or it can be too powerful and could cause your carboy to implode. More often than not, this is an expensive but effective method. It might not be the best idea for home winemakers, but it certainly is for commercial wineries handling millions of gallons of wine.

How To See if Your Wine Has Been Properly Degassed?

Congratulations! You’ve degassed your wine, but how to know if it was enough? The easiest way to find out is with a visual inspection. Swirl the wine and look for streams of bubbles. You can also pour some wine into a smaller container and shake it. A few bottles on the surface are normal, but there should be no effervescence.

Don’t be afraid to trust your palate. As a winemaker, you must train your senses to detect flaws because not everything can be measured. Have a sip and focus on the mouthfeel and the flavor. As with everything about winemaking, practice makes perfect. Go on, degas your wine, choose a method and master it. If you didn’t do this before, you’ll be amazed at the results. That’s wine to be proud of for sure!

Kelvin Teo founded Filled With Wine™ because one summer night, he noticed that his glass of wine tasted funny. It was only after he discovered that he stored his bottle wrongly that he realised the importance of proper wine storage. Since then, he has taken the art of wine drinking seriously and is now on a quest to help fellow wine lovers achieve the best drinking experience possible.