If you’ve ever forgotten an IPA in the back of your fridge, you’ve gone through the surprise, worry, and curiosity. Is it still good after several months?
The shelf life of an IPA is roughly 3 to 8 months, depending on the temperature it is stored at and how much light and oxygen it is exposed to. The more time passed since brewing, the less it will taste like the brewer intended. If an IPA has gone bad, you can tell because it tastes like skunk or has lost its hoppy flavors.
Keep reading to learn more about the science behind why an IPA goes bad and what you can do to extend its shelf life.
Does IPA beer expire?
With modern shipping methods, we don’t need to worry about whether the beer will spoil before getting to its destination. Although this was the motivation behind the original India Pale Ale that we love, it can be easy to forget that IPAs have a shelf life.
IPAs will expire given enough time. This is slightly different than food expiring, but it is still undesirable.
Spoiled beer isn’t dangerous like expired meat is. Chances are you’ve drunk a spoiled beer before. Between the alcohol content of beer and the pasteurization that most commercial beers go through, there won’t be any harmful bacteria.
Of course, you still don’t want to drink an expired beer, IPA or not. Expired IPAs will taste off at best and awful at worst.
4 reasons IPA beers will expire eventually
There are a few ways that IPAs become bad. Unfortunately, it usually isn’t just one aspect that goes bad. Instead each aspect of what makes an IPA good eventually spoils.
IPAs expire eventually because of the below changes. If these changes never occurred, the beer would last forever:
- Hop flavors change over time
- Hop aromas fade over time
- Oxidation eventually leads to off-flavors
- The beer has been skunked
If you’ve had an old IPA, you have likely noticed each of these aspects. For those lucky enough to have not tasted them, let’s explore what they’re like.
Hop flavors change over time
Those hop flavors that draw us all to IPAs are quite fragile. They will eventually degrade.
Hop flavors will fade over time. Citrus, floral, pine, and all hop flavors will become muted or even absent. If the IPA has a supplementary malt flavor profile you will taste this more. If it does not, the IPA will become bland.
Unfortunately, when the hop flavors begin to fade, off flavors begin to develop. Not to mention any hidden off-flavors will surface.
Hop aromas fade over time
Like the hop flavors, the aromas are very delicate. These, too, will leave the IPA after a time.
While fading hop aromas may not seem like much, our sense of smell has a big impact on our sense of taste. When the aroma fades, the character of the beer will be diminished.
This alone won’t kill the beer if the flavors are still present.
Oxidation eventually leads to off-flavors
This is where we start to get into the truly bad flavors. Oxidation is the bane of all brewers, craft or commercial.
At its worst, oxidation can show up in beer as a wet cardboard taste. Sometimes it is closer to cooking sherry. In the early stages, it is more of a metallic taste that can be hard to notice.
Essentially, most bad tastes in a beer that was fine a month ago are either due to oxidation or the next factor.
The beer has been skunked
The other big ruinous effect on beer is a skunk-like flavor.
Expired beers, or beers that have been left out, can develop a skunky flavor. This is especially true of IPAs. With their high hop content, they skunk worse than beers without many hops.
The mechanism behind this is why cans and brown bottles are better than clear glass bottles.
How long does it take for IPA to expire?
If you want to avoid spoiled beer, you need to know what your window is. Unfortunately, the answer is a bit complicated. It depends on a number of factors.
IPAs will expire after 3 to 8 months after packaging. However, depending on how the beer was stored during that time, it may be spoiled sooner. High temperatures will affect other factors, light will directly spoil as will oxygen, and time will degrade all.
Personal taste has some control here, but the IPA is spoiled for all at a certain point.
The temperature beer is stored at will have a big effect on how long it takes for beer to spoil. That said, the temperature doesn’t spoil the beer directly. High temps speed up the oxidization process of beer.
Cold temps will slow down spoiling, while hot temps will speed it up. There isn’t an exact temperature you should store beer at to minimize the spoiling process. In general, keep beer at 55°F or colder.
To truly minimize spoilage, you should try to minimize the next two factors.
The danger of light to beer can’t be understated. There is a reason most beer bottles are brown.
Light, specifically ultraviolet light, reacts with a compound that hops add to beer. This reaction causes a skunk-like flavor to develop. Having large hop bills, IPAs are quite vulnerable to becoming lightstruck. The more UV light, the quicker the beer spoils.
Beers that are packaged in clear glass bottles have no protection from light and will skunk much more easily.
One thing that apple slices and beer have in common is that oxygen makes them worse. Sealed beers don’t get much exposure to oxygen, but there are a few ways that oxygen can still spoil the beer.
Oxygen with access to beer will slowly affect the ingredients in beer depending on when the oxygen is present in the brewing process. Oxidation always occurs unless there is no oxygen in contact with the beer. Like light, the more oxygen, the faster it spoils.
Brewers use several methods to reduce oxidation, but it is impossible to stop completely.
Lastly, the factor that is slowly spoiling us all: time. There is nothing to do to slow this down aside from avoiding the above factors.
IPAs will spoil over time simply because the compounds that provide flavor and aroma are delicate. They break down and fade over time no matter what we do.
This is why it is best to drink your IPAs sooner rather than later.
How to tell if your IPA has gone bad
If you try a really old IPA, you will know immediately that it has gone bad. However, it can be harder to tell when the IPA is only a little past its best-by date. You will typically have to taste it to tell, unfortunately.
You can tell an IPA has gone bad if it tastes like skunk, however strong. Other off-flavors of a spoiled IPA include black currant, metallic, wet cardboard, paper, and leather. Another indication is a lack of strong hop flavors. Instead, the IPA will taste strongly of malted grains.
If none of these off-flavors are particularly strong, the only way to tell is to compare it to a confirmed fresh IPA by the same brewer. There isn’t a visual indication of a spoiled IPA.