When we talk about packaging your homebrew or wine after fermentation, you can bottle condition and wait a few more weeks for it to be ready (and have bottle trub) or you can do what we think the best option is—Just Keg It!

In this installment of Just Keg It, we want to discuss how to change your beers by making additions to your keg. In our store, we’ve encountered numerous brewers who have never tried to add anything to a keg, whether it’s to improve a flavor, add something new, or even try to “fix” a beer that didn’t come out the way you wanted. There are few things you can do to accomplish those things and it’s much easier than you’d think. But first, you’ll need some tools to do the job the right way.

Keg Hop Filters

These are by far the easiest way to make any additions to your kegs. They come in a various sizes, but I’ve enjoyed using a 3” x 12” version that fits well through the mouth of the keg and can hold a decent amount of material. These are easy to sanitize stainless steel and have a mostly mesh body with mostly solid ends that usually have smaller holes in them. The point being to keep the bulk of any added material inside the container while the fluid goes through it to impart flavor to the whole keg. Depending on how much space you leave, the flavor tends to be imparted fairly quickly into your beer. 

Mesh and Muslin Bags

These bags of different sizes are your next best option when adding something to your keg. Though, a fine mesh bag will beat a muslin bag every time. Basically, you might be able to fit more dry material into a mesh bag and squeeze it into your keg (or better yet, add it before you transfer and/or carbonate the keg). The mesh bags are easier to sanitize and clean. Where a muslin bag can be used, but we suggest using only a new and sanitized bag. The real problem with muslin bags being that the openings are uneven and can allow a larger amount of material through the stretched cloth mesh. 

Note: If you are using a keg hop filter, wrapping it in a mesh bag can be both a second defense against particulate and a way to hold a heavy addition together in the filter.

Fishing Line

Why the fishing line? Well, it is typically strong enough to hold up well when closed in the lid of the keg and is also easily sanitized. It doesn’t have to be fishing line, but you want a non-cloth material that is easily tied and cut and most importantly, thin bodied. Unless you have a hook of some sort on the inside of your keg lid, this line will need to come out through the lid. Which means under the O-ring seal. It can be helpful to use keg lube prior to adding a keg addition, just in case there is any time of seal break, but you should be fairly safe against such trouble if the line is thin and the seal of the keg is usually strong. Be sure to tie the outside portion of the line to something so that it cannot be pulled back through the lid if the materials you add end up heavy with liquid weight.

Non-Porous Weights

This one you can often use or leave out. Basically, you want something to help weigh down any light dry materials inside a mesh or muslin bag. They tend to float and take up space when first added and the weight can help them drop and soak much sooner. Many people like to use unscratched glass marbles or stainless steel ball bearings that haven’t been in any oils. Basically, you want something smooth that can be easily sanitized. 

Adding Flavors

Now that you have your set of tools to add something to your kegs, you have a variety of options to consider. First, you’ll want to know what you’re doing to the beer. Are you looking to boost a specific flavor or aroma? Are you adding something completely new and how strong do you want it to be? Are you trying to change the beer into something it wasn’t because it didn’t quite come out the way you wanted? 

Dry Hopping

This is easily the most added keg addition for most homebrewers. This is an excellent way to boost the dry hop character of any beer to where it can seem to be dripping with the hops. I’ve used this method and found major changes between the dry hop characteristics in as little as a week. I’ve also left them addition in there for the life of the keg and found that it continued to improve over several weeks. Mostly because the beer in the keg is kept much cooler, which can lead to a slower rate of transfer and a slower onset of any vegetal character. But of course, you can always keep replacing the dry hop addition to really double or triple the character of what you started in the secondary—which might even change a bland or uneven beer into something better. I’ve used both whole hop and pellet hop additions and the major difference (other than selection) is obviously that pellet hops break down and might make it through the tightest mesh, stainless or otherwise. This can then end up in your beer or at the bottom of your keg and then into your glass or bottle. 

Note: Expect sudden foaming if you add dry hops to a carbonated beer. There are a vast number of nucleation points on those hops, so if you are adding these to a carbonated beer, do your best to quickly submerge the addition and close the lid. With weight a bag should sink once soaked and with a keg hop filter, you will be able to push it in. Be sure your hands are sanitized or you are wearing disposable sanitized gloves during handling.

Adding Fruit and Spices

It isn’t always obvious to brewers, but when you really want to capture a fruit flavor and aroma—especially with the sweetness of the juice—you can add cut up fruit and fruit puree directly to your keg. For example, say you have a hefeweizen and you want to give it something extra for an event and you know it may not sit around for long. Why not add raspberries or pour in some actual raspberry puree in a keg filter? In a very short period of time you’ll have a flavor that could be as simple as a hint to something deep and rich. Obviously, puree will be blended with your beer sooner, but you run into the problem of pulp that might escape the container into the poured beer. While chunks of fruit can take a little longer to infuse and can add some water, but should still get the flavors you’re looking for in a fairly short period of time. 

As an aside from fruit, you can also add spices. Whether it’s a few sticks of cinnamon or herbs like rosemary. Just aim for more whole additions that aren’t powdered and you’ll have less of it end up in your pour. I’ve found that a blend of all of the above can work quite nicely. Like a pound of roasted coconut and almonds with a dash or three of vanilla in a porter or stout. It all depends on how much flavor you want. You may have to give each element some time to do it’s job, but you can always remove anything if it is growing too strong in flavor in the keg. 

Adding Wood

Finally, we come to a way to age your beers on wood without the concern of the beer sitting in a carboy exposed to oxygen for a long period of time. Or better yet, as a way to quickly add wood character to just the right amount and then be able to remove it before any more is added. 

You’d basically treat these wood additions the same way by sanitizing them or letting them soak in spirits that you want to get some flavor from, then add those cubes or chips or spirals into the keg with some (or all) of the liquid you soaked them in. Bourbon Oak Aged Stout? Drop in the bourbon and oak until the oak seems just right, then remove it and let it meld. All the while, the beer was under a blanket of CO2. Or how about a margarita beer? Make a dose with light acidity, use some lime peel or lime dominant hops, and grab some light oak chips and tequila for a quick soak and addition that won’t need to stay in the keg for long. As always, you only need to lightly cover the wood with the liquor and you can always reserve some of it to add in later if the flavor isn't strong enough.


Keg additions are clearly a very easy route for changing up your beer in both large and small ways. Plus, you can easily control the subtlety of the flavors you add by being able to sample the keg in cold and carbonated form at just about any time you are ready. If it’s where you want it to be, remove the addition. If it isn’t or seems like it may still get better, leave it. Just remember to be careful with your sanitation practices and any sudden carbonation release when you add those additions to cold carbonated beer. 

—Greg Etzel

Semi-Media Director/Special Event Coordinator TBI, Producer, Writer, Host, and Host Wrangler Come and Brew It Radio, Homebrew Consultant, Lover of Experiments