In a world full of coffee storage tools, it can be difficult to find the perfect solution for storing your beans. From shrinking chambers to mason jars, there is a seemingly endless supply of options available today. How does one decide on what is best for maximum preservation? In general, there are three types of coffee containers—airtight, displacement, and vacuum—and we are going to break down each of their key features. Get your Bill Nye goggles on. It’s time to learn about the science of storage!

Airtight

The most popular container in an average household has got to be airtight containers—think mason jars, recycled glass (e.g. large pickle jars), and containers with a pop-top lid. These are great options for organization or keeping your coffee and dry goods protected from pesky invaders like ants and roaches during the summer. Airtight jars are also considered an affordable and sustainable choice. You can commonly find people picking up bulk dry goods at the local grocery to refill their jars at home, instead of buying things like plastic bagged rice over and over again. But unfortunately, that’s where the benefits seem to end. As far as preservation goes, there is no discernible difference between an airtight container and pre-bagged products. Your grocery items are still exposed to a considerable amount of oxygen whether the lid is on or off. This allows for steady oxidation, resulting in minimal preservation long-term.  

Hands holding Atmos Vacuum Canister in Matte White with brewed coffee in Mighty Small Glass Carafe

Displacement

Displacement containers are another popular option, especially in the coffee and tea market. These devices rely on shrinking the area in the device, usually with a lid that you push into the container. As you press the lid, air rushes out, removing “empty space” between the lid and it’s contents. Despite the fact that this type of product removes air, in practice, there isn’t much difference between this type of storage and folding up your coffee bag, smooshing the air out, and tying a rubber band around it. Sure, it limits oxygen exposure, but oxygen is still present, albeit much less than in airtight containers. 

Vacuum

Atmos (and other vacuum containers) pumps oxygen out of the container, reducing pressure, and minimizes rate of oxidation. Vacuum canisters typically have a separate tool to remove oxygen from the container, much like wine vacuum pumps. Our Atmos inventor, Drew Cosgarea, found that having the air pump separate from the device was a big letdown—you’re more likely to lose the pump, and it isn’t very convenient. This is why Drew designed the lid as an all-in-one vacuum tool. In order to seal and pressurize the container, crank the lid back and forth. This is another super cool design element. Since people are so accustomed to turning jar lids back and forth, vacuum sealing the Atmos lid with that same cranking motion would be second-nature for users.

As you move the lid back and forth, you’ll feel resistance and see a little green dot show up on the top of the lid, which lets you know that the interior is pressurized. Your coffee is protected from air, moisture, odor, and other funk from seeping in. Our testing has shown, as long as you properly store suggested dry goods in Atmos, you will benefit from up to 50% increased lifespan. When you open the container, simply press the button in the middle of the lid, and you’ll hear the soothing sound of air swooshing back into Atmos. Perfect for all those ASMR Stans out there. 

GIF of Marshmallows in Atmos Vacuum Canister

But be wary, Atmos does not bode well storing flours, sugars, matcha, powdered seasonings (like turmeric or cinnamon), or other powdery substances. It is also not meant for liquids of any kind. Water can interfere with the filters in the lid, and powders can mess up the strength of the rubber seal (powers on rubber allow air to enter Atmos, thus depressurizing the container quickly).

Pros, Cons, and The James Hoffmann Experiment

In a side-by-side comparison of airtight, displacement, and vacuum storage containers, the differences are quite stark. James Hoffmann, YouTube coffee influencer extraordinaire, put about a dozen containers to the test—tasting coffees stored in various airtight, displacement, and vacuum canisters—followed by an espresso-pulling test to better highlight any differences. In his video, Hoffmann admits there wasn’t a huge difference between the coffees during his tasting, but that vacuum canisters did, in fact, perform better. 

The espresso test showed more distinct differences between storage devices. As many coffee nerds know, with espresso, the devil’s in the details. Espresso isn’t nearly as forgiving as pour-overs and drip coffee, every little difference will express itself for better or worse. When Hoffmann pulled espresso from airtight containers, he found shots that poured faster had much more channeling. Channeling is a bad thing—it is when water finds its way through areas of least resistance/density in the portafilter, which results in uneven extraction. The crema was also weak and quickly dissipated after a couple minutes.

With vacuum canisters, the result was a bit better. After six weeks of testing, none of the espresso shots poured exceptional cremas, but vacuum canisters slightly outperformed the competition. The displacement canisters sat right in the middle, nothing too exceptional, but nothing horrible, either. 

Following testing, Hoffmann voiced his overall preference for vacuum-sealed canisters. When he compared Atmos with the two other vacuum canisters tested, he found that Atmos was the one he would prefer to keep. He said, “The [Atmos is the] nicest, most thought through. Would be my choice to keep…. It tells you when to stop, with the green button showing at the top of the lid. Although there’s more complexity with cleaning [the lid]. Of the contenders tested, Fellow tested best. Great features, feels well made, and would be my choice.” 

Final Thoughts

Despite the fact that vacuum-sealed containers are not new, the unique design of Atmos allows for a more  enjoyable experience, all while powerfully preserving your favorite roast. But don’t feel limited to storing only coffee in your Atmos. Coming in three sizes and three finishes, Atmos is a great addition to your kitchen for storing dried goods like pasta and rice, cookies, loose leaf tea, relaxing “herbs,” and much more.