Corny Kegs vs. Carboys
Most homebrewers who bottle dream of ditching bottles for kegs. But you do not need to build or buy a home draft system to get many of the advantages that kegs offer. A lot of beer styles need that secondary fermentation (or more appropriately called, “conditioning”) step. This has traditionally been done in a glass carboy. The one advantage carboys have always had over any other vessel is that you can see what is going on inside of them. Whether this was fermentation bubbling away, or watching your beer clear so you don’t bottle a super cloudy beverage. This is pretty much their only advantage, and an advantage that is arguable. Here we will break down how to use kegs for all they are worth!
When it comes to storing, transferring, and clearing their beer, breweries almost exclusively use stainless steel. Normally this would incur a huge cost investment, but not when you use what homebrewers have been utilizing for years — kegs. Nicknamed “corny” kegs because the most well known manufacturer was a company named Cornelius, these are reconditioned canisters that formerly held soda syrup. Hence their other name, “soda” kegs. They are pure stainless steel, and come with hardware that works extremely well in a homebrew environment. They come with dedicated ports for both gas and liquid. This is important if you are using them for more than dispensing cold beer, because unlike commercial kegs, the gas and liquid do not have to be hooked up at the same time. They also usually come with a dedicated relief valve, which will be important later on.
Normally when we transfer our beer into a “secondary”, we use a 5 gallon carboy. One thing almost all homebrewers have run into is not having enough beer to fill up to the neck of the carboy. Head-space, like Star Wars Episode One, is not good. The last thing we want post-fermentation is our beer in contact with oxygen. When used as your secondary, a keg will allow you to purge whatever headspace there is with CO2. Simply siphon beer out of your primary fermenter into the keg, close it up, and then purge. If you do not have/want a full CO2 system for draft beer dispensing, you can use inexpensive CO2 cartridges and a dispenser to purge the headspace at a minimal cost.
And then comes the purpose of using a secondary fermenter in the first place. Let’s tackle them all, and why kegs are superior.
Strictly to get a little (or a lot) of age on the beer. Apart from being able to purge the head-space with CO2, the keg is stainless steel and will not let damaging light in. It also has handles for when you need to move it around. If you like brewing big beers or sours (like yours truly), you tend to start to acquire quite a few things in various states of aging. Kegs have a smaller foot print, and are also stackable. Imagine having three batches of beer taking up the same amount of space as a jacket hanging in a closet.
Dry hopping. When transferring a beer into a carboy for dry hopping, you have some limitations. First off, you want to contain the hops in a way that makes transferring and cleaning easier. Putting pellet hops in a muslin bag works well, but doesn’t catch them all. Stainless steel mesh balls (commonly known as tea balls) hold them in much better. But these mesh balls are not able to fit into the neck of a carboy. If choosing to use whole flower hops, you need them to sink to the bottom. Putting them into a muslin bag weighted with glass marbles or stainless steel weights and then into a carboy is very doable. Getting it out easily is a very different matter. Both of these scenarios are negated with the large opening lid on a keg.
Transferring your beer. Our beer is always at its most vulnerable when exposed to air. We have been conditioned to limit how much we disturb our precious beer, whether that is at the transferring or bottling stage. If putting your beer into a secondary using a carboy, the beer gets exposed to outside air at least twice. Once from moving it out of primary fermentation, and once going into your bottling bucket. While good sanitation techniques make this almost moot, I’m the kinda guy who doesn’t like to take chances. When a beer is put into a keg post fermentation, you can move it using CO2, so that the beer will never touch outside air. If you don’t have a CO2 system, there are portable CO2 devices similar to the ones that inflate bicycle wheels that use food grade CO2. Simply hook a sanitized piece of beer line between the “out” posts on the kegs, and apply pressure to move it over.
There are even more advantages to using kegs over carboys, but that’s going to have to wait for another posting. Can you imagine bottling your beer the exact same way breweries do? Beer so clear you can drink out of the bottle with no sediment getting in the way, should you be so inclined. Yeah, it’s easier than you think. Stay tuned my friends.