How To Freeze Your Coffee (and why you should!)

Freezing specialty coffee can extend the life of your precious beans for weeks, months, and even years.

I know what you’re thinking because it’s how most people react when I talk about freezing coffee. It’s a curious look paired with a puzzled question that usually sounds something like, “Are you…serious?”

Yes, I’m serious.

Although the quality of coffee your parents kept in their freezer when you were a kid was less than specialty, there’s valid reasoning behind keeping that can of Folgers in sub zero temperatures. I didn’t start freezing coffee until I had conversations with Umeko Motoyoshi (@umeshiso_ and @wastingcoffee) and Tom Finch of @manchestercoffeearchive and learned more about their process and reasoning.

They’re not the only ones that are freezing their coffee, though.

George Howell has been freezing vintage coffee for years, Canadian roaster Phil and Sebastian freezes their green coffee as soon as it lands, and cafés around the world like Proud Mary have also started incorporating freezing practices into their public service process.

Here’s the bottom line:
I’m convinced that freezing coffee is an imperative element of the sustainability of the industry, and I think you should be freezing your coffee at home too!

Why you need to freeze your coffee

Coffee is a living thing, born from the cherry of the coffee tree and fermented like your favourite wine. Although oxygen gives life to most things on this terrestrial ball, it has a habit of taking life from your coffee beans. 

Oxidation is the name of that mortal process that turns fruit brown and your coffee stale, so we must try to minimize it. We store coffee in bags with one way valves, we keep it away from light, and we grind it on demand. All of these measures are to minimize oxidation and maximize freshness. I store the coffee on my bar in Fellow Atmos canisters to minimize oxidation, but when I’m saving coffee for longer additional measures need to be taken.

That’s why you put your milk in the fridge, too. The cool temperatures slow down the active bacteria in your food to keep it fresh for longer. To keep your coffee from going stale you’re going to need to lower its temperature and reduce its exposure to oxygen.

Your goal by freezing coffee is to:

• lower temperature

• minimize oxidization

You could freeze your coffee for a couple reasons. First and foremost, freezing coffee allows you to extend the life of the coffee you already have and lower your anxiety about drinking it when it’s fresh. Alternatively, freezing coffee can turn your freezer effectively into a time capsule. If you ever have the privilege to come across a special coffee that leaves you wanting the bag to never end, you can store a few doses in the freezer to take out on a rainy day - whenever that rainy day comes!

Here’s the actual math of it:
My friends at Manchester Coffee Archive suggest that every day frozen in a domestic freezer at approximately -18ºc is the equivalent to 90 days at a room temperature of 25ºc. That's well, a lot of days.⁣⁣

So can you just throw your coffee in the freezer?

What you need to freeze your coffee

If you live in Canada like me, you might be able to put your coffee outside for 4 winter months of the year (although I wouldn’t recommend it). My official recommendation is simply to store your coffee in the freezer. Your fridge freezer will work fine if you have room, but depending on the amount of coffee you plan on freezing you might want to scour the internet for a used chest freezer. Don’t worry - a dedicated coffee freezer is not pretentious at all.

You can’t just throw that coffee in the freezer though. Sure it’ll be cold, but you haven’t addressed the element of oxygen. It’s not even enough to throw your one-valved bags in there either. I’ve tried that a few times, but those valves don’t seem to keep that classic “freezer taste” off of your beans.

To freeze your beans effectively you’re going to need to vacuum seal them. If you’re into cooking sous vide you may already have a vacuum sealer and you’re one step ahead of the rest of us. If you don’t already have on, they start on Amazon for around $60. I like this one a lot!

If getting your spouse to agree on buying a vacuum sealer for freezing coffee isn’t in your future, you can still freeze coffee with things you likely already have in the house! All you need is a ziploc freezer bag, a straw, and a set of lungs.

How to freeze your coffee

If you’re using a vacuum sealer, you can empty the bag that your coffee comes in and seal the bare beans or simply vacuum seal the entire bag. Emptying the beans mostly feels unnecessary to me, so I usually just seal the entire bag. Umeko Motoyoshi shared a helpful tip in their recent book The Guide To Not Wasting Coffee. “If the coffee bag doesn’t have a valve, I poke a tiny hole in it so the vacuum sealer can suck the air out from inside of it.”

If the vacuum sealer wasn’t in your budget, it’s time to get out your straw. Follow the same steps for the vacuum, except in this case you’re the vacuum. Close the ziploc all the way to the corner and around your straw. Expel all the air in your lungs, parse your lips, and take the biggest breath you can muster. In one swift motion remove the straw and seal the bag when you’ve sucked out all the air.

Regardless of what method you choose don’t forget to label the bag the coffee and the date it entered your freezer! If you sealed bare beans remember to put the roast date on the bag for reference as well.

Additional benefits

Freezing coffee has many benefits but none more important than wasting less coffee. Keeping your coffee fresh for longer means that you’ll be throwing less coffee away and enjoying it much past the mythical 4 week mark. Although it’s the most important, it’s not the only benefit of freezing coffee.

Image from Proud Mary’s Facebook Page

Proud Mary has been freezing coffee for café service using innovative methods to virtually freeze time at the peak quality. “We’re constantly using coffee that’s either too fresh or too old; it’s all over the place,” Proud Mary Coffee founder and owner Nolan Hirte told Daily Coffee News recently. In their Portland, Oregon shop you’ll see three Mahlkönig EK43 grinders behind the bar with their hoppers contained in a custom built freezer. Not only does this keep their coffees at peak freshness for service, it also allows them to use these workhorse grinders and achieve exceptional results in unimodal grind distribution. Frozen coffee seems to grind more consistently, producing a more even particle size and enabling the baristas at Proud Mary to dial in their shots with coarser than traditional grind settings.

You’ll see this behaviour at home too, and the benefits will impact a cheap grinder much more than they will an expensive EK43. Your home grinder can definitely use help producing a more even particle size, so grinding from frozen just might be the upgrade you’ve been looking for.

So go ahead, give freezing coffee a try! Let me know if you have any reservations about the whole thing or if you’ve tried it before!