I love my kegging setup. Kegs are much easier to clean and sanitize than a couple of cases of bottles, artificial carbonation is more predictable than priming sugar, and you don’t have to commit to another whole bottle when all you want is a nightcap half pint.
Perfect! Except that your homebrew is only at its best at home, or at least within reach of your keg. You can always pull a sample off to take a growler to a party or to gift some bottles to a friend, but it’s never as good as on draught. Maybe your friends won’t complain, but entering those bottles in a competition will give you all the brutal honesty you can take.
Don’t assume that’s just the cost of convenience. There are a couple of good options for taking your draught beer to go. If you’ve got an extra hundred bucks, then a beer gun or counter-pressure bottle filler will work nicely, but there’s also a cheaper alternative.
Before we dive into that, though, there are some general tips to preserving your beer’s carbonation, regardless of how you fill your bottles.
Carbon dioxide solubility in beer is highly dependent on pressure and temperature. Splashing the beer around or even having a lot of turbulence in the flow creates pressure drops that pull CO2 out of solution. Similarly, as the beer warms, it loses some of its capacity for dissolved CO2. We want to minimize both of these effects when we move the beer from the keg to the bottle.
The obvious pressure tip is to get the beer smoothly into the bottle. That’s why these solutions feature a wand or bottling tube that reaches all the way to the bottom of the bottle. It’s just as important, though, to drop your serving pressure down to 2-4 PSI first. This slows the flow, reducing the turbulence. You can also balance some of the carbonation loss by kicking the pressure up a day or two beforehand to put more CO2 into solution. Then when you lose some during bottling, you still end up with what you need.
You can eliminate temperature issues by chilling everything that will touch the beer. The beer gun or racking tube as well as the bottles should be cooled down to the same temperature as your beer, or even a little cooler. If you’re just filling a growler for the party tonight, sanitation is less of an issue, but otherwise, you should sanitize everything before chilling it.
Now that we have some general principles (go with the flow and chill out), let’s look at whether we want to buy or build our solution.
Fancy A counter-pressure bottle filler is not quite the same thing as a beer gun, but they’re both set up to let you purge your bottle with CO2 before filling it. The counter-pressure filler seals the bottle and holds it under pressure while the beer is dispensed. This extra pressure keeps more CO2 in solution, so your bottled beer will be just as bubbly as the draught version. The beer gun doesn’t control the pressure, but it’s more ergonomic to use. Follow the tips above and your carbonation should remain largely intact.
If you only want to fill a bottle or two, this might be overkill. Aside from the monetary investment, it takes more effort to set up and sanitize the equipment and then break it down for cleaning afterwards. On the other hand, if you’re entering beer for competition, or you have a keg of something big you want to lay down for cellaring, then purging the CO2 is quite important.
DIY For the longest time, when I wanted to bottle from a keg, I used a 12 inch piece of vinyl tubing crammed onto the end of my cobra tap. This sort of worked, but the carbonation drop was pretty noticeable. The problem is that the size differential between the tap and the tubing creates turbulence, driving CO2 out of solution. This modification solves that.
Instead of vinyl tubing, we’ll use a straight plastic tube, such as a section of a racking cane. Rather than forcing tubing over the end, we’ll press the plastic tube up into the cobra tap until it seats. This is a fairly tight fit, but the tube will butt up against a flange in the tap, maintaining a more even flow.
Next, cut the other end of the tube at an angle. This allows the beer to flow even if the wand is pressed against the bottom of the bottle. Additionally, you can slide a #2 stopper onto the wand to use it like a counter-pressure filler. It’s not quite the same, because it won’t purge oxygen from the bottle, but it allows a more even transfer.
Using it is simple:
1. Sanitize the tap end and the wand.
2. Attach the wand to the cobra tap.
3. Run a squirt of beer through the wand to prime it.
4. Insert the wand into the bottle and seal it with the stopper.
5. Open the tap all the way. As the beer fills the bottle the pressure inside will build and slow down the flow. Squeeze the stopper to bleed off some of the pressure as needed.
6. Once the bottle is full, pull the wand out to the lip of the bottle, which will leave some headspace. 7. Open the tap for just a moment to fill that headspace with beer and foam. 8. Cap the bottle.
Whether you buy the gear or roll your own, with these tips, your beer can leave the house in style.