Spend enough time getting lost in the world of coffee, and you’ll start to notice that nobody agrees on much of anything. For every tightly-held belief when it comes to the selection, storage and preparation of coffee beans, there’s an equal and opposite opinion that others will argue just as vehemently.
Case in point: keeping coffee in the freezer. Should you do it?
Some say yes; it’s the only way to keep coffee fresh after opening. Others say no; it will destroy your coffee beans.
See the problem here? In this case, both sides of this argument are a little bit right and a little bit wrong. Let’s go deeper into what happens when you freeze coffee beans, and why that may or may not be such a good thing.
How to Keep Coffee Fresh
Coffee is at peak freshness about 72 hours after roasting. It’s pretty much all downhill from there, but there are a lot of ways you can keep your coffee fresher, longer.
The four main things that you want to protect your coffee beans from are heat, light, moisture and oxygen (in other words, just about everything). Heat causes coffee to degrade more quickly. Light breaks down its organic cell structure. Moisture encourages bacteria growth and affects flavor. And contact with oxygen causes oxidation, much in the same way metal will begin to oxidize, which robs coffee beans of flavor and aroma.
Basically, the best way to keep your coffee beans as fresh and flavorful as possible is to store them in an opaque, airtight container in a low-humidity environment, away from heat and direct sunlight.
Your freezer does check a lot of those boxes. But regardless of whether or not you freeze your coffee, you should definitely do these things for the best coffee drinking experience:
- Buy freshly roasted, whole bean coffee.
- Grind your coffee each day, right before brewing.
- Use coffee within three weeks of its roasting date.
Arguments for Freezing Coffee Beans
The basic idea behind freezing one’s coffee is that, when done correctly, it protects coffee beans from all the threats mentioned above, thus preserving its flavor and aroma for a longer period of time.
This is basically true, although the “when done correctly” part of that last sentence is quite important. Over the long run, being kept very cold will preserve coffee beans, allowing you to enjoy them a month or more after they are roasted.
There’s a second reason some people freeze their coffee, that being that it improves grind uniformity. This part is actually completely true. Coffee beans that have been frozen will grind more evenly, which can help you avoid a lot of frustration if you’re using an inexpensive grinder.
Arguments Against Freezing Coffee Beans
Okay, there are a couple of reasons why some people argue against keeping coffee in the freezer. One is that frozen coffee can pick up flavors from other things in the freezer. This is true. You definitely don’t want coffee that carries notes of frozen shrimp and leftover lasagna.
The second argument you might hear is that your freezer is a high humidity environment, and all that moisture will wreck your beans. This one is simply not true. There is very little humidity inside your freezer because, in general, cold air has less potential to hold moisture than warm air.
That lack of moisture is actually what causes freezer burn. When you place something moist (like that leftover lasagna) in a very cold, dry place, the environment will eventually draw the moisture out of it, causing it to freeze and crystallize. Fortunately, roasted coffee beans tend not to contain much moisture, so freezer burn isn’t a huge issue.
Here’s another argument against keeping your coffee frozen: temperature fluctuations resulting from moving your coffee in and out of the freezer will rob it of flavor. This is true. All those hot-cold-hot-cold changes actually affect coffee at a cellular level, which causes it to lose the essential oils that help give it flavor.
Final Word: When Should You Freeze Coffee Beans?
In a nutshell, if you plan on using your coffee while it’s still in its prime—i.e. within two or three weeks of its roasted date—then there is absolutely no reason to keep your coffee in the freezer.
Doing so can actually do more harm than good. Not only will the daily in-and-out degrade the flavor as mentioned above, but it will also introduce moisture (think of the condensation that forms when you take a cold thing out of the freezer) which completely counteracts all the benefits of keeping your coffee in a supposedly dry place.
That being said, if you buy coffee in bulk, and won’t be able to use it all up before it starts to severely lose freshness, then freezing is an effective way to extend its lifespan.
Granted, freezing doesn’t completely halt the degradation of coffee beans, but it does slow it down quite a bit. One can conceivably keep coffee in the freezer for up to two months without noticing significant loss of flavor.
How to Freeze Coffee Beans
Okay, so you’ve bought way too much coffee to use in the next couple of weeks, and you want to freeze it so you can use it later. Sounds like a plan!
Here are a few coffee freezing tips to help you do that more effectively:
- Freeze your coffee inside an airtight container to keep it from absorbing odors and flavors from other items in your freezer (also, keep all the other items in airtight containers too).
- Once your coffee is frozen, keep it frozen until you’re ready to use it.
- Keep frozen coffee in a deep freezer or chest freezer if you have one. It gets opened less often than the freezer in your fridge, and maintains a more stable environment as a result.
- Freeze coffee in smaller portions, so you can remove a few days’ worth as needed without having to return it to the freezer.
- Don’t worry about light. It’s dark in your freezer except when you open it, and that isn’t enough to cause any major harm to your coffee.
- Label and date your coffee so you know when it was frozen. Don’t expect it to taste fresh longer than two months, even if you’ve done everything right. Sadly, nothing lasts forever, even in a deep-freeze.