Knowing how to carbonate beer correctly is as important to the brewing process as choosing the right grains, hops and yeast to use when brewing any style of beer. This is because the CO2 levels in your beer have a major influence on the characteristics of your beer. The aroma, mouthfeel and head are all directly impacted by the carbonation levels.
There is no question that the science behind carbonation can be complicated, however achieving good levels in your beer is not difficult to accomplish and anyone including the novice brewer can do it successfully once they understand the basics of how to do so.
In this post we are going to cover the following:
- The different methods to carbonate beer in a keg
- How to carbonate naturally in a bottle with priming sugar
- How to carbonate your beer using nitrogen
But before we get into those topics it is important that we quickly cover the topic of achieving proper carbonation levels in your beer.
Carbonation Levels 
When it comes to making beer I strive to keep things very simple as I find many of the websites and books on the subject overcomplicate many aspects of the brewing process and as a result end up turning people off of this great hobby.
By keeping to this philosophy of simplicity I have discovered that most of the complicated techniques make very little to any difference in the quality of the beer you make. Attempting to dial your beer into exact carbonation levels is one of the aspects that can really complicate the brewing process if you let it.
While there are guidelines put out by organizations such as Brewer’s Association and the BJCP that advise exactly what levels of CO2 should be in your beer, my advice is unless you want to dive deep into dialing your beers into the precise carbonation levels each style calls, don’t worry about it. If you are like me and are just looking to make good tasting quality beer as simple as possible then don’t over think this part of the process, keep it simple.
The fact is that most beers are served at a very similar range anyway, typically in the 2- 3 volumes of CO2 range. What you will find is that all of the carbonating methods traditionally used and that we are going to cover in this post will bring your beer into that range.
However if you want to explore this topic further the following two tools will help you get started:
For naturally carbonating your beer with priming sugar in bottles and kegs there are tools like the following one that will help you determine the exact volume of CO2 you want in your beer. Priming sugar calculator
For force carbonating in a keg the following tool will allow you to dial in the exact level you are looking for. Force carbonation table
How to Carbonate Beer in a Keg
There are traditionally 4 methods you can use to carbonate your beer in a keg. 3 of them use CO2 and would be referred to as force carbonation and the 4th uses priming sugar. We are going to look at each individually.
But first a quick word on force carbonation as many people appear confused over this term. Most mistakenly believe it is the quick method to carbonate with CO2.
Although there is a quick method that we are going to look at today, the fact is any time you are using CO2 to create the fizz you are force carbonating, whether it takes you 14 days or 15 minutes.
The following are your options for using a keg:
Set It and Forget It Method – This is the most widely used method and simply involves filling your keg up with beer, putting it into a kegerator or keezer; hooking it up to your CO2 tank, turing on the gas to 12 psi and leaving it alone to do its thing until your beer is carbonated to the level you want.
I used this method for years and can attest it works great. It is definitely one of the more reliable methods to achieve consistent results. It’s only downfall is the time it takes to fully carbonate your beer. Expect to leave your keg on the gas for a min of 10 – 14 days. Which if you have ever bottled beer you know is pretty close to the same time frame. The advantage this method has over bottling is how convenient it is to keg.
Burst Carbonation Method – This is now my favorite method. It is much faster than the Set it and Forget it method. Using this method you can achieve excellent levels of carbonation within 48 hours.
It is not as fast as the next method we will discuss but it does not come with the risks that one does either.
To do this method some people will tell you to hook your keg up to the gas and turn it up to 30 psi for 24 hours and then dial it down to your serving pressure.
However I have found the best way to do this is to turn your gas up to 35 psi for 24 hours and then completely remove it from the gas for 24 hours.
After the 48 hours you can then turn the gas back up to your preferred serving pressure. I actually used this exact method to carbonate all of the beers in my brew pub.
If 48 hours is too long for you but you still want to use this method, some people will set the gas at 40 psi for 18 hours or 50 psi for 12 hours.
Crank and Shake Method – This is for the overly eager brewer who wants to be able to carbonate beer in 15 minutes. We have all been there and I have used this method when in a pinch a couple of times myself.
The first time I gave this a try was at Christmas one year, I had underestimated how much beer I would need on tap for the holidays and ran out. But fortunately I had a brew that was still in the fermenter and had finished fermenting for the most part.
I quickly cleaned my keg and refilled it with this new beer and used the crank and shake method. It turned out ok, it was not the best carbonated beer I had ever had that is for sure, but it was drinkable.
There is a risk involved with this method that you can create too much foam in your keg and it will pour out foamy. But sometimes it is a risk worth taking.
For this method you simply crank up your gas to 30 psi and start rolling your keg back and forth. I found the best way to roll it was on my lap. Simply sit in a chair and start rolling the keg back and forth on your lap. It will take approximately 10 minutes to reach ideal carbonation levels, but you can try it every minute after the 5 minute mark to see how it looks.
Naturally Carbonate in a Keg Method – I enjoy this method also as I like the taste of a naturally carbonated beer. The process here is the exact same as what you do if you are bottling beer except without the bottles.
The only difference is in the amount of priming sugar that you use. Some people recommend using the same amount as you would when bottling, however others recommend you should dial it down to half. I have always used half the amount, but I do not see a problem with using the same amount. If it becomes too fizzy simply purge the CO2 from the keg.
How to Carbonate Beer in Bottles
Bottle conditioning beer is what most homebrewers do starting out before progressing to kegging. To this day I still try to brew enough beer to have some to be able to bottle condition 1 or 2 beers. I really enjoy the taste of a naturally carbonated beer in a bottle.
It’s advantages are its simplicity, lower cost, and great taste. It’s disadvantages are that it takes time and is a lot more effort and work. Mixing the priming sugar with the beer, cleaning and sanitizing each bottle, filling them all up and capping them takes some time. But to many people it is worth the effort.
The following are some important things you will need to consider if you use this method…
Choosing Your Priming Sugar
Although you could use pretty much any sugar to create carbonation the following are the most common used forms:
Corn Sugar (Dextrose) – This is the most commonly used form of sugar when bottling. It dissolves quicker than the other sugars, it does not cost much and unlike some of the other options it does not affect the flavor of the beer at all. For a 5 gallon batch you will want to add ¾ of a cup of corn sugar.
Cane Sugar (Sucrose) – Also referred to as table sugar or granulated sugar. This is another option that comes in handy especially in a pinch if you run out of corn sugar on brew day. I have used dextrose and sucrose both interchangeably, although in the past I have claimed to be able to tell the difference in taste it is in reality quite negligible. Cane sugar does provide more natural carbonation than corn sugar so for a 5 gallon batch use ⅔ of a cup.
Here is a taste test video I did some time back where I naturally carbonated the same beer using corn sugar and cane sugar in separate bottles, it was an interesting experiment to try:
Malt Extract – This is a popular sugar source used by many brewers. You do have to use a bit more than the other two we just looked at, 1 ¼ cup will work fine.
The only thing to be aware of with using malt extract as your priming sugar is that it tends to cause a boil over when preparing it for the bottling bucket. Very similar to what happens during the brewing process. It can also create a krausen-like ring at the top of the beer level in your bottles which is nothing more than a cosmetic problem. Neither of these will alter the flavor of your beer.
Honey – This is a fun sugar source to use at times as it can add a nice flavor to your beer. However it can be tricky to use because the gravity of each jar of honey varies from each other.
If you want to get technical with it you could dilute it and take a gravity reading, which I have never done and believe it to be a difficult thing to do. To keep it simple just get a decent source of honey and use 1 cup for a 5 gallon batch.
Carbonation Drops – These drops are a great alternative to priming sugar because they are simple to use, provide a great level of carbonation and you are assured that each bottle is getting the same amount of sugar and hence carbonation levels.
There is also less work involved with using them, you simply drop one into each bottle, fill the bottle with beer and put the lid or cap on. They are made up of 27% glucose and 73% dextrose. Use 1 drop for a 12 ounce bottle and 2 drops for 22 ounce bottles.
Here is a post that goes into detail about the difference between carbonation drops vs priming sugar.
How to Add Priming Sugar
We have already explained how to do so with the carbonation drops. You can also add 1 tsp of sugar directly to each bottle. I have done this successfully in the past but it is not recommended by many in the brewing community as it is quite time consuming to add the sugar directly to all of your bottles. It is also not a precise method and you can easily over or under carbonate your beer. It also poses a risk of infection because the sugar you are adding was not boiled
Your best option is to transfer your wort over to a separate bottling bucket. Now boil your sugar in 1 – 2 cups of water and let it cool. Then add it into the bottling bucket. Gently stir the beer in order to have the sugar evenly distributed.
Connect your tubing to the bucket at one end and the wand at the other. Fill the bottles to the top, when you remove the wand the beer level should have dropped to 1 – 1.5 inches from the top. Put the caps on the bottles and place them in an area of your home that you keep at room temperature.
Pressure Fermentation
Fermenting your beer under pressure is a growing trend in the homebrewing industry. It is a unique method of brewing that saves you time, money and effort.
The basic concept is that instead of allowing the CO2 to escape through an airlock during fermentation you trap it within the fermenter and the beer absorbs it. There are a lot of advantages to doing this and one of them just happens to be that it carbonates your beer naturally during the fermentation process.
I am not going to get into a full training on how to do this in this blog post as it would become too lengthy, however you can check out this complete guide to pressure fermentation if you want more info on it.
How to Carbonate Beer with Nitrogen
Using nitrogen in beer was around long before people were even aware of this technique. Traditional ales such as stouts, porters, bitters and milds were traditionally stored and served in wood casks. There was no such thing as forced carbonation back then, all of these beers were naturally carbonated.
In order to serve them they would hand pump them from the casks to the taps. The hand pumps introduced air into the casks and pressurized them. Oxygen is made up of 78% nitrogen. The result was a creamy and rich pint that had a nice head.
While you can carbonate with nitrogen the most popular method of nitrogenating your beer is to still carbonate it naturally or forced with CO2 but to a lower volume level of around 1.5. Then use the nitrogen to serve the beer. You can purchase a special nitrogen tap that creates smaller bubbles and creates the rich and creamy characteristics you are looking for.
English ales look great and taste delicious when they are nitrogenated like this.
Frequently Asked Questions
How long does it take to carbonate beer in a bottle?
You will have carbonation within 5-7 days and the beer will be drinkable. However the carbonation level will not be ideal until at least 2 weeks in the bottle. It is also recommended to let your beer condition even longer then the 2 weeks as it will significantly improve in taste.
Can I still cold crash if I am going to naturally carbonate?
The concern that people have here is that all of the yeast will have fallen out of suspension and when you transfer to the bottling bucket there will not be enough yeast left to go to work converting the sugars to CO2. Have no worries you can definitely cold crash your beer and there will be more than enough yeast left to do the job.
Can I still use Gelatin if I am going to carbonate in bottles?
Yes, just like with cold crashing, using gelatin or any of the other fining agents will leave enough yeast in your beer to be able to convert sugars to CO2 without any problems.
Why is my bottled beer over carbonated?
There can be a few reasons for this.
The first is that you bottled your beer before it was done fermenting. This happens to many novice brewers who are in a hurry. What happens is there are still residual sugars left that would typically not be, so the yeast continues converting them over while in the bottle along with the other sugar you added. This creates too much CO2.
The second reason is you added the improper amount of priming sugar. Stick to the guidelines I gave you in this post and this should never happen to you.
Thirdly your beer may have become infected during the bottling stage. This is why it is crucial that you clean and sanitize everything the beer is going to touch, buckets, spigots, mixing spoon, hoses, bottling wand, bottles and caps.
What can I do if I over carbonate my beer?
If you kegged your beer this is a simple fix. First off turn the gas off and then purge the keg of all CO2. Wait 4 – 8 hours try a sample of the beer if it is still over carbonated do it again.
Continue this process until ideal levels are reached. It may take you a couple of days to get it adjusted correctly. If you are in a big hurry after purging the first time you can give your keg a shake to stir up the CO2 levels and purge again. Keep purging and shaking until the level you want is reached.
If you bottled your beer there is not much you can do if anything to lower the carbonation level. I have heard of people cracking the cap and letting carbonation out and recapping quickly but clearly this would only work on swing tops or screw on caps and to me it is a bit sketchy as you run the chance of introducing oxygen into the bottle and causing an infection.
For me if I have over carbonated a bottle I simply pour it into my glass and let the foam subside and pour some more. Bit of a pain but at least I will not lose the beer to an infection.
My beer is still flat, why?
If you have been carbonating in a keg or a bottle for the required time periods and your beer is flat then you have a leak and CO2 is getting out.
With bottles that means your caps are no good and not maintaining a seal.
With kegs it means you have a CO2 leak somewhere in your system. It could be between the regulator and the tank, or the regulator and the keg. Your lid might not be seated correctly, your gas and liquid connections may not be tight or the rings have worn out, etc. Keep your equipment in good condition, lube all of the rings, make sure all connections are tight and you will reduce the chance of this happening.
Addtional Resources
Bottling homebrew everything you need to know.
Kegging homebrew the full monty
In Conclusion
Learning how to carbonate beer properly is an important but not overly difficult part of the beer making process. Simply determine which method will work best for you, experiment by adjusting the CO2 and sugar levels as you go and eventually you will have it down to a science and fine tuned to your preferred levels.
If you have any questions on any of what we have covered feel free to ask me in the comment section. I always respond to questions.
Now go get your brew awnn…
Cheers Big Robb is Out!
