In this new article, we will discuss how long beer actually can last, where it can and should be stored and at which temperature range, what equipment to buy, etc. We will also see if it makes sense or not to carry out some additional processes, such as pasteurization, since those could potentially increase the lifespan of our beer.
So in short, how long does draft beer last? Under the right conditions, beer can last up to 10 months. For this to be possible, it will need to have low bacteriological activity as well as low oxygen levels and, once it is already in the keg, it will need to be kept at 2 or 3 degrees Celsius, but not any lower since it could freeze.
Of course, there is a lot more information regarding this topic, such as what equipment you should consider using in order to make your beer keg last longer, etc.
When and where to store our beer
Beer, with the exception of some cellaring styles, cannot be aged. Let’s understand beer in the following way: its quality goes up to a certain point and then it stagnates, and that is where oxygen starts to create problems. So, once we can say that our beer is ready and has reached its optimal point, the most advisable thing to do is to consume it.
There are several reasons why a brewer might forego drinking, giving away, or selling their beer and instead prefer to store it. One of them may be that they really like a batch, in which case, instead of storing the beer in a keg, the best thing to do would be to store a few liters in 330cc cold bottles.
Another reason, perhaps, is that momentarily they have no one to sell it to. In that case, they can keep some of the beer stored in kegs, although if the amount to keep is very high, they should ask themselves if they are not brewing with a very large surplus, which is not recommended either.
Another reason, which I think is the one you’re all reading this article for, might be if you purchased a Keg for, let’s say a party, and want to know how long beer will keep in it and if you can drink whatever is left over the course of a month or two.
If our intention is to store a batch of beer for a long period of time, we must be aware that the most important factor to consider, actually, is the state the beer is in beer when kegged. Even if we leave our beer at the “correct” temperature and carbonation, if it has large amounts of oxygen or bacterial load, our beverage will inevitably acquire undesirable flavors or off-flavors.
The fight against oxygen is a very complex one and it’s already a losing battle. However, there are ways we can store our beer and help it keep for longer, as well as also to improve the quality of the product considerably.
Here’s the best way of storing a keg:
Kegerator
A kegerator, or keezer, is nothing more than a refrigerator or freezer on which taps have been installed to store and serve beer more easily. In the previous article on how to bottle beer, I went over what the entire bottling process is all about, how to do it properly etc., and I also mentioned that you need to have a lot of bottles ready to go which takes up a lot of space and can also be a hassle. Well, using a Kegerator makes everything simpler since you don’t need to deal with dozens, if not hundreds of bottles.
For this and other reasons, we should really consider the use of a kegerator as one of our main options.
In case you are in the initial stages of learning how to brew beer, you should ask yourself some questions: If you’re a brewer, are you planning on selling your beer in the next two years? Is it possible to acquire a freezer or refrigerator, kegs, and taps for your budget? And do you have the necessary physical space?
Beginner homebrewers usually brew smaller-sized batched (generally 20lts or 5 gallons), which means that using a keg might not be all that advantageous, but once you start to scale up your production, kegs start making a lot more sense.
One thing to keep in mind if you’re a homebrewer is that, unless you give away a lot of the beer your produce, or drink it all extremely fast which we all know won’t end well, you probably won’t have enough space to continuously brew new batches and store all of the bottles since, over time, they will end up taking up way too much space.
For example, if you brew 4 times a month using 20lt, or 5 gallon, equipment, you would probably have to consume or give away between 60 and 70 liters every month, which is way too high of a number. This is where Kegs and Kegerators come in: Storing your beer in a keg, especially if it’s in a kegerator, means that it won’t take up as much space and the beer will also keep for much longer.
Also, a kegerator can definitely improve the quality of our beer. Why? you ask, Well, by transferring the beer to a keg and from there, directly to our glass, we prevent bottling it, which is where oxygen generally has a chance to come into contact with our beer.
When transferring beer into a keg, you can do this using CO2 which will reduce, or even remove, all of the available oxygen inside of the keg, allowing your beer to stay fresh for longer.
How to Dispense Beer
To give you a better idea of how long your beer will last, it is also really important that you understand the different dispensing methods there are and how they can impact beer quality.
Counter-Pressure with CO2
CO2 is used to carbonate beer and it’s completely harmless to it, which means that it can be used to push the beer out of the keg and into your glass without ever letting oxygen into it and, therefore, increases the beer’s shelf life.
Kegerators use CO2 counter-pressure to serve beer, which means that there’s never going to be any oxygen inside of the keg, even if it’s almost empty, which is not the case with the next two methods.
Manual Pump
These pumps dispense the beer in a similar way to how it’s done by using CO2 counter-pressure, but they do this by injecting oxygen.
As I just explained, oxygen should be kept as far away from beer as possible if we want to preserve its quality and not allow it to quickly degrade.
With manual pumps, there is also a multitude of problems that come along with their use, such as over-pumping and excessively foamy beer, and they are generally not recommended unless the keg can be emptied quickly.
Electric Dispenser Pump
Electric dispensers use electricity to cool the beer while it’s being dispensed instead of having a frozen coil to do this. These types of pumps also introduce oxygen, just like the manual ones do, and will negatively impact your beer’s shelf life.
So, should I get a dispenser that works with C02 or Oxygen?
Unless we are absolutely sure that the beer will not be in the keg for more than a couple of hours, we should dispense it using the counter-pressure method with CO2. Just leaving the beer in contact with the injected oxygen for one day means that, organoleptically speaking, it will deteriorate a lot.
It is not only during kegging that we should opt for CO2, but it is something that we should always keep in mind since once the wort is done, meaning after the boiling phase has been completed, contact with oxygen should be prevented.
At what temperature should beer be kept?
There is a little rule that you can use which serves as a reminder: 3-30-300. What does this mean? A beer at 30 degrees for 3 days will have the same aging as a beer for 30 days at 20 degrees.
And in turn, these beers will age the same as a beer that is kept at 2 or 3 degrees for 300 days. This shows us the great importance of temperature and how essential it is to keep our beers at the coldest temperature possible without allowing them to freeze.
At what pressure should beer be kept in a keg?
If the keg is properly sealed, meaning that there’s no CO2 leaking out, it should not lose its carbonation. Therefore, the beer will remain at the pressure that your style demands even if the keg has been tapped.
To answer this question, it is essential to take into account two other variables: the temperature of the beer and the volumes of dissolved CO2 we want to reach.
The simplest and most convenient answer is to set the regulator to 1 BAR (15 psi) of pressure and keep the keg refrigerated at a constant 5 degrees Celsius.
After approximately 2 days, our beer should have about 2.5 volumes of dissolved CO2 (a more than acceptable value for the vast majority of styles).
How do we know if the beer in the keg has gone bad
Here we have two main alternatives:
- Generally, in a dark beer, oxidation will convert malt flavors into flavors reminiscent of sherry or rotten fruit. If the beer is a lighter color, the oxidation reaction will gradually strip the beer of the hop and malt flavors and end up tasting like wet paper or cardboard
- If the beer has contamination problems, it will taste vinegary, sour, etc.
Pasteurized vs. unpasteurized beer shelf life
Pasteurization of craft beers is a topic that generates a lot of debate. Brewers actually choose to pasteurize or not according to their needs. This topic deserves a separate article, but here I will try to give you an approximate idea of how it affects a beer’s shelf life.
Pasteurizing has the advantage that it ensures that no chemical process occurs inside the container, and I’m not just referring to the formation or mutation of bacteria, but also in somewhat more isolated cases, it may happen that if there is some residual sugar present, the yeast may become active again and generate an undesired re-fermentation, resulting in off-flavors and excess carbonation.
On the other hand, by pasteurizing we are removing many valuable elements from our beverage, so much so, that it is actually frowned upon for a craft brewery to pasteurize its beers.
On a home brewer’s scale, pasteurizing is really unnecessary. For those of you who have been brewing for a while now, you’ve probably, at some point, kept a bottle for a year, drank it, and there really wasn’t anything wrong with it.
Essentially, pasteurizing beer will increase its shelf life, but beer can already be kept, if stored under the proper conditions, for close to a year, so generally speaking, it’s not necessary to pasteurize it, even less so for beer that was homebrewed.
Conclusion
Is it really necessary for us to store our beer for a long time and also, how long does beer last in a keg?
Kegeators are undoubtedly the best options to store and improve the quality of our product. They are a great ally in the fight against oxygen, which leads me to repeat myself again because it’s a really important concept to get right: Never use oxygen to serve beer, always use CO2, keep the liquid at low temperatures, and, in case it comes out with a sour, vinegary or another off-flavory kind of taste after a while, it means that the batch was ruined, probably due to oxygen exposure.
If the beer is stored in a Kegerator, basically at a low temperature and in optimal conditions, it can last up to almost a year in perfect condition.
Finally, answering the question of whether or not to pasteurize, which only applies to brewers and not to someone who bought a keg, I honestly think that at home brewer levels it is totally unnecessary.
All we will be doing is stripping the beer of its “live” characteristics that make it distinctive. What is really beneficial is to follow proper brewing practices so that the beer makes its way into the keg or bottle in its best form possible.
Perhaps it is better, in case we are in the initial stages of learning, to brew smaller batches of beer in exchange for making more styles and getting more experience.