search

The Best Ways to Store Ground Coffee and Beans

how to store ground coffee

What happens when you leave coffee out? Well, it turns out that it does a lot more than just get cold. And what about the grounds? Yet again, if you really want it to taste how it was made to, you’re going to need to do much more than just pick a pack and pry it open.

How you decide to package and store your coffee contributes majorly to its taste, aroma and freshness. As much as it may seem a nuisance to do, believe me when I say, if you want the coffee you buy to hold its grounds, you make sure it’s stored safely. As much as it may seem a nuisance to do, believe me when I say, well-kept coffee keeps you wanting more.

What Turns Coffee Bad?

If you weren’t already aware, you’ll be pretty disheartened to hear that pretty much anything can turn coffee bad. With the primary culprits constituting air, heat, light and moisture, the idea of keeping it safe may seem overwhelming.

And though the reasons why coffee can get so easily stale are as complex as they appear, to stop the sullying of your morning cuppa is as simple as can be.

Air

Coffee oxidation contamination is the main antagonist in ruining the flavor of your coffee. So, what does it do? The actuality of the reactions and science behind this go way beyond the scope of even an undergrad.

Simply put [1], when air gets in contact with coffee grounds, it reacts with the fats present within it. Known as unsaturated free fatty acids, these compounds enhance the taste of our coffee, but their cohesion with air alters their molecular structures and subsequently their taste too.

Lucky for those buying their coffee beans whole, the lower surface area of the beans compared to grounds has been shown to make it more resistant to oxidation staling.

Heat and Light

Unless the writing on your coffee packet is written in old English, you’re not going to need to worry about it having expired.

Though it may seldom expire, if you’re keeping it under your skylight window or in direct sunlight, it might just ruin the taste so bad that it might as well have.

A hot, arid environment causes the much-savoured oils in your beans to evaporate leaving you with a dry and unbearably acidic flavor profile.

Not only that, but if you’re making this mistake in combination with it being in an air abundant environment, you’re inadvertently accelerating the oxidation process even more!

Moisture

If you think all the evidence points to storing coffee in the fridge, think again. Though it is true that it’s an optimal place for stopping oxidation, heat and sunlight, the detrimental effects posed by fridge moisture levels might just make it worse than keeping clothes-peg closed coffee on the countertop.

Studies [2] show that coffee grounds exposed to a very humid environment will be burn much faster and taste much more bitter.

And, though some say the bitterer the better, a survey that gave coffee-drinkers coffee from a moist and a dry packet showed participants siding overwhelmingly with the packet held in good conditions.

How to Store Ground Coffee and Beans

I admit, it seems like a billion bad things are happening to your coffee and you’re helpless to stop them. However, as you’ll find, the solutions are simple and straightforward.

There are scores upon scores of ways of storing your coffee beans the right way, of which the main three are air-tight containers, vacuum-seals and zip-lock bags. Each of which all have their own flaws and practical uses, all acting as simple solutions to a complicated problem.

Air-tight Container

Though one coffee packet can be drunk over the course of, at times, years, making sure it doesn’t go stale for that long is really hard. Using air-tight containers and Tupperware has been shown [3] in a study to drastically increase coffee bean shelf life.

Not only is this because the coffee can’t oxygenate, but also because it radically decreases harmful microbial development in your coffee beans that can make you sick and impact your health.

The study used polyethylene bags to store the grounds, the world’s most common plastic. Considering you’ve probably already got about ten of these around the house, if you want to keep your coffee beans beaming, there’s no doubt that it’s the most practical solution.

Remember, the darker the bag, the better it protects against sunrays and ultraviolet radiation, the likes of which can ruin certain health benefits [4] that well-kept coffee holds, ultimately lowering coffee shelf life.

Something else to keep in mind is that unground coffee beans have a much higher shelf-life, so if you’re a hoarder or only an occasional coffee consumer, you might want to consider beans if you aren’t using them already.

Vacuum-Seal

There isn’t a huge deal of difference between a vacuum-seal and an air-tight container [5], in fact, it wouldn’t even be a semantic error to call a vacuum-seal bag a type of air-tight container.

The difference is, vacuum-seal containers are a variety that do their jobs much more thoroughly, at times, successfully keeping coffee from going rancid after more than 2 years. As much as you probably don’t have the bag or the sealer itself lying around, you might just want to change that.

Not only do vacuum-seals work on coffee, but on any low moisture food [6], so if it’s not for the grounds, then why not the rest of the pantry?

Do bear in mind, whether your vacuum seal bag is translucent or not, that you should do your best to keep it in a cool environment sheltered from direct sunlight, as the vacuum seal does not protect against the dangers that heat poses on your coffee deterioration.

Also, make sure you buy compatible bags that work with your vacuum sealer, depending on the brand and make. Otherwise, you might make for a redundant and poorly pressed vacuum sealed bag.

Zip-Lock Bags

The trusty zip-lock bag combined with a zip-lock mechanism is a sure-fire way to ameliorate your morning macadamia milk mocha. Though it does, for the most part, work in the same way as a vacuum seal bag, unlike its air-tight vacuum requiring counterpart, it’s prone to carbon dioxide build-up.

Coffee, up to 2 weeks after its cultivation and processing, releases trace amounts of carbon dioxide [7]. Seeing as zip lock bags are often-times the most pressurized of the 3 storage methods, this gaseous build-up can often be hazardous.

At best, you can expect no significant downsides to this build-up, but at worst, the bag may explode, showering your kitchen in a brown brew blizzard!

Though this is an unlikely scenario, you might just want to cover for it by buying zip-lock bags with pre-existing valves that let out carbon dioxide while keeping oxygen out.

Also, all three forms of preservation do, in most cases, use polyethylene plastic. This has been identified by a Harvard study [8] as a plastic that can easily seep into food in trace amounts, especially if they are in an above room temperature environment.

Once the plastic is consumed, it has the potential of increasing metabolic disorders such as obesity and infertility.

Though the amount of plastic you’ll be consuming won’t probably be enough to be carcinogenic, consider using a different material if you can’t keep your coffee in a cold cupboard.

Can You Freeze Coffee Grounds or Beans?

Yes, but there’s a couple caveats. As was covered before, your fridge and freezer can often be a place of high moisture and an area of aroma rich scents.

Since coffee beans, by nature absorb and, in a way, consume the aromas around them, amalgamating with the miscellaneous fridge ingredients and their smells might just ruin the coffee.

If you don’t want to have the hassle of preserving your grounds [9] but still want that fresh from the plant feel, then the freezer is a solid compromise.

My recommendation would be to place the coffee beans or grounds in the centre of your fridge drawers, as the back and sides of your refrigerator circulate cold, moist air and aromas. Also, if capable, place the coffee as far from meats and fragrant foods as possible.

Optimum results [10], in fact, suggest that you use a combination of both an air-tight container and a freezer. If you do decide to keep your coffee coverless for extended periods of time, it might suffer the fate of freezer burn.

This happens when the ice in the freezer sublimes, going directly from a solid to a vapor state. This affects the moisture content both in and out of the coffee bag, making its eventual flavor more rubbery and bitter.

Though a high moisture content is harmful to the taste, so too is a low one, coffee beans are a delicate concoction and the compounds that account for its flavorful aroma are dependent on the small amount of water holding the bean together.

When you’re ready to finally sieve out a serving, remember, don’t microwave your coffee grounds back to room temperature if they’re in a volatile plastic. You might just get more than you bargained for.

The good news is that the majority of the water contents in your coffee beans [11] or grounds are intramolecularly cohesive. And that medical mumbo-jumbo means that the water within the beans can’t freeze and thus makes the bean last much longer without congealing or separating like curdling milk or cheese.

If it weren’t for that, you’d be hard pushed to come back to your freezer and see anything even remotely salvageable to drink. The bottom line is, though quantitative tests have cited that frozen coffee is more bitter, you might just prefer that sort of taste.

If you don’t want to go to too much trouble, then I can promise you that you really don’t have to. Plus, if you really want coffee well done, the barista has always seemed to know how to do it better anyway.

Coffee Freshness Over Time

Coffee may not age like a fine wine, but its shelf life, especially when well preserved, can reach upwards of 2 years. That said, throughout those two years, it only ever deteriorates in quality, with an eroding palate, profile and flavor.

If you really want high quality caffeine, you’re not going to get it from anything above a month or two old. Just like anything roasted, once you’ve cooked the beans into fruition, the sooner you taste them, the better.

Post-roasting, the oils that add to the complexity of the coffee become volatile and unstable, especially in the presence of oxygen, heat, moisture and sunlight.

And so, the best advice really is to shield the beans from time and temperature and consume them as soon as your daily allowance allows it.

A study [12] investigating the freshness of coffee over the course of a year clearly showed a linear regression between time before consumption and quality of flavor.

An interesting additional find was that coffee containers made of aluminium were significantly more effective in conserving both depth of flavor and mouth feel. This was especially true when compared to paper packaging that reportedly appeared lumpy and unbearably oily.

You wouldn’t know it today, but the conservation of coffee and search for high quality brew material is a relatively new one. The beginning buzz actually only arrived 45 years ago coming from coffee shop non-conventionalist Alfred Peet.

A point of contention within measuring coffee freshness, however, lies within the espresso. As opposed to pure coffee ground brews, the age of coffee beans used within the espresso have a potentially positive effect on both the texture and the taste of the drink.

The older a bean is, the more carbon dioxide it has expended, meaning that, when turned into an espresso, it gets less creamy. So, if you like your espresso runnier than hot honey, you might just want to expend your older beans and enjoy a more custom coffee.

How to Preserve Freshness

Unless you’ve got the frivolous madness within you to buy your own coffee plantation, you’re not going to have the control you need to make your beans last forever. Not only that, but you might not even be able to fully control the air, moisture, light and heat that plague the palate.

The next step after that might just be to roast them yourself but again, we really don’t expect you to go that far with it.

Worst case scenario, your coffee won’t kill you. And if you just want a bag to last a month or two, of which is largely enough time to finish a packet, just pick one of the three packaging choices and you’ll be fine.

Conclusion

So, whether you’re looking for conveniency, meticulous quality or luxury, there’s always a way to make sure you’re drinking the morning coffee you deserve.

Between the much-propagated polyethylene air-tight parcel, sparser vacuum seal and zip lock bag, it’s in your hands. Enhance your home coffee drinking experience today and test-ride your tried-and-true brew with a new and improved cup of well-preserved grounds or beans.

Make the effort you think it’s worth to up your coffee game today, or let’s be real, feel safe that the Barista behind the counter most likely already knows all of this.

  • Evelyn J Stafford
  • Evelyn J Stafford

    Evelyn is a Coffee enthusiast and writer for Wins Coffee Bar. Her work has appeared in Bean Scene, The Home Kitchen and other publications.

    Read moreTwitterEmail

  • is-french-press-coffee-bad-for-you?
    What happens when you leave coffee out? Well, it turns out that it does a…
    COMMENTS
    latte-vs-traditional-coffee
    What happens when you leave coffee out? Well, it turns out that it does a…
    COMMENTS
    Cappuccino-vs-Coffee
    What happens when you leave coffee out? Well, it turns out that it does a…
    COMMENTS
    JOIN THE COFFEE CLUB!
    Be the first to read breaking reviews, recieve special discounts, and all the happenings!