Chances are that at some point you have come across coffee that has either already turned or is well on its way to going bad. Maybe it is coffee that has been sitting in the back of your pantry since forever that you fatally rediscover, or maybe it is a coffee at a friend’s or your grandmother’s that just doesn’t taste right.
Whatever the experience the moral of the story is that coffee can and does go off or at least reaches the point of no return. So when is the point of no return? How do you know if your coffee is still good to drink? Does it make a difference if it is whole beans or pre-ground? How long does coffee last?
These are a few of the questions we will be seeking to answer for you in this article.
The Lifespan of Ground Coffee
The short answer is that pre-ground coffee is best used as soon after grinding as possible but can be safely consumed weeks or even months after purchase. It really all depends on what you are looking for and how picky you are.
If you are a coffee snob (and I mean that as a compliment rather than an insult) then you probably shouldn’t be using pre-ground coffee at all but should be grinding your own with a decent burr grinder. Similarly, if you are paying the extra money and buying quality beans from a specialty coffee shop or roasters then you really shouldn’t buy more ground coffee than you will use in about 2-4 weeks. After this period of time the distinctive flavours of the beans will disappear into a more generic and bland coffee flavour.
However, if you usually buy your coffee in bulk and from a local supermarket or grocery then chances are that you are less snobby about your coffee and don’t want to waste your paycheck just on coffee. If so then ground coffee from your local supermarket is best consumed in 1-2 months after purchase.The reason that this is longer than for specialty coffee is that coffee in supermarket shelves has usually been roasted and perhaps grinded 6-18 months before purchase and so gives a more generic coffee taste.
Coffee found on supermarket shelves will also usually have a best before date printed on the back of the packet. This is an easy way to figure out whether your coffee fits into the specialty or mass produced category. If it has a best before date it is likely mass produced, but if it has a roast date then it is likely speciality coffee. Coffee with a roast date is best consumed within 2-4 weeks of the roast date for maximal flavour.
So how long does coffee last?
|Type of Ground Coffee||When should it be consumed for the best flavour?|
|Ground Specialty Coffee (from a specialty coffee shop or roaster)||2-4 weeks after roast date|
|Ground Mass Produced Coffee (from a grocery)||1-2 months after purchase|
Why Does Coffee Go Bad and How Do You Know?
The reason that coffee eventually goes stale and reaches the point of no return is usually due to a process called oxidation. Basically, the presence of oxygen causes the coffee to lose much of its distinctive aroma and flavour over time. This comes into play for both whole whole coffee beans and also pre-ground coffee. However, the process is accelerated when it comes to ground coffee.
The reason for this is that the outer shell of coffee beans acts as a natural storage container to preserve the distinct flavour and aroma of the beans. As soon as this natural protection is removed through grinding, more of the coffee bean is exposed to oxygen and so the process of going stale is accelerated. This is the reason that I can basically guarantee you that your favourite coffee shop doesn’t use pre-ground coffee but grinds on demand. Because grinding fresh coffee beans on demand is the single best way to get the maximum flavour out of the beans.
However, the good and bad thing about coffee beans is that when they do go stale they are still usually safe to use. This is great because it means that you can keep using beans over a long period of time. But it is also a bad thing because it means that lots of people are unconsciously using beans that are well on their way to going stale and settling for sub-par flavour.
The two big giveaways that coffee is going stale is that it loses that distinctive coffee aroma and smell, and that the flavour becomes more generic, cardboard-ish, and generally unpleasant. This means that you can’t actually tell whether coffee beans are still good simply by look, it is the flavour and smell that are the signals. It is also worth noting that the darker coffee beans have been roasted, the quicker they go stale.
Ground coffee goes stale a lot quicker than whole coffee beans and so the fresher the ground coffee is the better it will taste.
How do you correctly store Coffee Beans?
One of the key components to how long your ground coffee lasts is how you store it. Basically coffee is best stored somewhere that is airtight, cool, and out of direct sunlight. Because oxygen and moisture are the great enemies of ground coffee, they need to be as well protected from these two things as possible.
The best idea for storing coffee is in an airtight container that is placed in a cupboard or somewhere that is not too hot and out of direct sunlight.
Some coffee especially from specialty coffee stores comes in bags that are already airtight and often have a one way valve that allows gases to be released without letting oxygen in. If your coffee comes in one of these bags then this is a perfectly adequate way to store your coffee. But if the bag can’t be completely resealed so as to prevent oxygen entering, then we recommend investing in a special airtight container.
There are a number of rumours and myths and whispers around about the way you should store coffee. One of the most common is that coffee is best kept in the fridge. This is incorrect and you shouldn’t do it. Coffee kept in the fridge doesn’t actually last longer and can lead to the coffee absorbing some of the aromas and flavours of other things in your fridge. Think fish smelling coffee…
Another of these common controversies is whether coffee should be kept in the freezer to preserve it for longer periods of time. Somewhat surprisingly this is actually a fairly effective way to preserve coffee beans. While many baristas tend to look down on this practice, Coffee Expert Scott Rao in his book Everything but Espresso states that
“Freezing is a fantastic long term storage plan because it dramatically slows oxidation and loss of volatiles.”
Freezing coffee shouldn’t be the first port of call but should only be done if for some reason you aren’t going to use your coffee in the short term. If so then place the coffee in an airtight plastic bag, squeeze the air out and then place it in the freezer. Also coffee that has been frozen shouldn’t be defrosted and then refrozen.
The fresher the coffee the nicer the taste and the best storage is in an airtight container in a cool and dark place.
So how long does coffee last? Well I hope that I have convinced you that the answer is, it depends. Coffee is always best consumed sooner rather than later for maximum flavour and aroma. So it depends how picky you are about your coffee. If coffee is your thing then you really shouldn’t be using pre-ground at all, or if you do you should be purchasing high quality beans and using them within 1-2 weeks of purchase.
However, for the more general coffee lover who just enjoys his or her morning brew without worrying too much, ground coffee should usually be consumed within 1-2 months of purchase.