Keg Carbonation Explained
The oldest kegs of beer in the world date back to roughly 4500 B.C., where they were used by ancient Egyptians and Mesopotamians to brew beer from wild grains.
Today, kegs are still used in beer brewing, though now they’re paired with sophisticated technology. In this guide, we examine the details of a popular part of modern beer crafting: keg carbonation.
Keg Carbonation: Defined
Keg carbonation is an umbrella term for distinct methods of carbonating beer in a keg. The most utilized keg carbonation methods are:
- The carbstone method
- Bottle conditioning
- Force carbonation
Carbstone Method
The carbstone method involves submerging a porous, CO₂ diffusion device, called a carbonation stone, and using it to pump carbon dioxide into the brew.
While it poses fewer upfront costs and can take less time than some other methods, the carbstone method also has significant drawbacks. Brewers can explore this method in greater detail with our quick guide to carbonation stones.
Bottle Conditioning In A Keg
“Conditioning,” a process of adding priming sugar to a sealed bottle or keg of fermented beer. The priming sugar will entice the yeast to eat the sugar and generate CO₂ as a byproduct.
This is an older method of carbonating beer in a keg. While it’s traditional, it’s slower and less reliable than other methods.
Pressurized Keg Carbonation (Force Carbonation)
When brewers use the term “keg carbonation,” they’re almost always referring to this method of force carbonation.
To start keg carbonation, a keg is filled with beer and set at a specific temperature. Then, pressurized carbon dioxide is forced into the beer using a CO₂ cylinder. Typically, a CO₂ regulator is used to adjust the rate and degree of carbonation infused into the beer.
Force carbonation is the most common of the three keg carbonation methods. It’s faster, and it offers more reliable and precise carbonation.
How Does a Force Carbonation Keg Work? (Slow Vs. Fast)
A force carbonation keg is a keg setup with a CO₂ cylinder and regulator. This equipment allows brewers to force pressurized CO₂ into the beer in the keg, which then dissolves.
Slow force carbonation pressurizes the CO₂ at a lower PSI, and it takes longer to dissolve the full, desired amount of carbon dioxide in the beer. Slow carbonation is a good way to avoid over carbonation.
Fast carbonation uses a higher psi when pressurizing the CO₂. It can also involve jostling or rolling the keg to excite the yeast and increase the speed at which the CO₂ dissolves.
While fast carbonation doesn’t take as long, it can result in using more CO₂ than intended, and it risks over carbonation.
Keg Carbonation FAQs
Keg carbonation is a popular method of giving beer that sparkle. But, it isn’t straightforward. Here are some vital answers to a few frequently asked questions.
How To Carbonate Beer In A Keg Effectively?
We recommend slow carbonation over
fast methods for best results. To force carbonate beer in a keg effectively, follow the steps of the slow force carbonation method.
- First, let your beer rest in between fermentation and carbonation.
- This gives yeast time to settle and allows for the reduction of diacetyl, a compound that can alter the beer’s flavor.
- Then, clean and sanitize your keg.
- This prevents residue from getting into your brew.
- CO₂ tank pressure can effectively sanitize and remove oxygen from the keg.
- At this point, you can fill the keg almost completely with beer.
- Make sure to leave a few inches of room for expansion due to the added CO₂.
- After that, connect the CO₂ source, cylinder, and pressure regulator to the keg.
- Close and pressure-seal the lid of the keg.
- Remove any remaining oxygen in the keg by “burping” the pressure release valve.
- Check for leaks.
- A portable leak detector can be helpful in noting any leaks around the lid.
- Set the correct CO₂ pressure on the pressure regulator, depending on the type of beer you want to make.
- Use a Carbonation Chart or pressurization table to choose the right settings.
- Let the beer sit and intake carbon dioxide.
- Two days is a decent amount of time for a low-carbonation beer, like a lager or stout.
- The longest you’d want to leave beer to carbonate is fourteen days
- This length of time is only appropriate for a highly carbonated beer, like a German wheat beer.
What PSI Is Required To Carbonate Beer?
The best PSI to carbonate beer will vary depending on the beer temperature, the desired amount of carbonation, and how long you want to carbonate.
Fast force carbonation typically starts with the CO₂ regulator set at 30 PSI. Once the beer reaches the desired carbonation level, the regulator pressure is reduced to serving pressure.
Serving pressure is typically 10-12 PSI for most beers, while wheat beers and Belgian beers are served at 15-20 PSI.
Slow force carbonation typically pressurizes CO₂ between 8-12 PSI. Use a keg carbonation chart to determine the optimal PSI for your beer.
How To Pressurize A Keg For Carbonation
To pressurize a keg for carbonation, connect your CO₂ source (usually a CO₂ cylinder) to the keg’s gas inlet and the pressure regulator.
If setting up the carbonation equipment proves challenging, see if there is any guidance or setup instructions from the manufacturer available online.
Once the equipment is connected, you can pressurize a keg for carbonation by running CO₂ from the cylinder into the keg, setting the regulator at 30 PSI.
How Long Should You Carbonate Beer In A Keg To Get The Results You Want?
If you’re using the fast, force carbonation method, you should carbonate beer in a keg for as little as 12 hours to, at most, 3 days.
If you’re using the slow carbonation method, you should carbonate beer in a keg between 3 and 12 days. 5-10 days is fairly typical.
Smarter Carbonation With Quantiperm
At Quantiperm, we make accurate carbonation easier than ever with our advanced inline carbonation technology. Our systems can carbonate your beverage inline precisely. It is significantly faster and requires no baby sitting and removes any bottleneck associated with the traditional carbonation methods!
If you want fast, precise carbonation in your brews, every time, contact our team at (602) 903-2158.
