My sister heard something on TV about coffee and she asked me to check with my coffee friends about its accuracy. So I am doing so. “When you open a bag of coffee and air gets to it, it only stays fresh for 3 days.”
Roasted coffee plays by different rules. Once you roast a coffee it’s shelf life is a little more of a time bomb. But this is where you might start getting mixed messages from coffee professionals. Some might say you have up to 6 months, and based on the ‘expiration date’ on coffees found at the grocery store, there are many that passively suggest a rather extended amount of time. Others are of the mind that coffee has somehow gone bad after a mere 7 days off of roast. Everyone is entitled to their opinion but, as is true of many things in life, we at Roast Ratings feel the ideal falls somewhere in between.
All coffee loses its delicate nuance and bright character over time, diminishing to basic flavor notes that lean toward low chocolate or caramel tones. It’s natural. You have two basic flavor sets in your coffee- flavors inherent to the coffee itself and flavors related to the roasting process. While there are definitely variations on the balance of the two flavor sets, aging follows the same basic pattern. The roasting process can get really, but for our purposes in the aging discussion I’ll keep it as simple as possible.
Roasting allows certain gasses in the coffee to finally escape which, from an experience standpoint, will be a bit funky with these gassy flavors for the first couple of days. In the cup they usually come across as metallic. After the majority of the gas has escaped the coffee’s flavor will work its way towards its peak which can vary but, when handled with care, is typically between 4 and 20 days off roast. This is when the flavors will be most vibrant and complex. After this it will make its usually mellow from vibrant to lower tones and, while it might not be quite the coffee you began with, it is far from having gone ‘bad’. When coffee has officially gone stale it has a strange sharply sweet aroma. That’s how you know it’s over.
So what can you do to extend the flavor life of your coffee? The changes in coffee’s flavor, green or roasted, boil down to 2 simple things- time exposed to air and higher temperatures.
Temperature is pretty easy to address. Keep it at a stable room temperature. There is a reason that we let our green coffee “hang out” in their countries of origin for 3-4 months. The climate where coffee grows best is pretty temperate, they never get crazy hot but they don’t really get cold either. When it comes to moisture in the coffee stability is key, so being stored in a space that’s around 60-70 degrees Fahrenheit and away from light is the ideal. The same rules apply with roasted coffee at home. Rather than former conventional wisdom of freezing your beans, find a spot in your kitchen cabinet for everyday storage. It’ll stay cool, but not cold, and not be exposed to a lot of light. That solution is absolutely free!
Now, exposure to air is the more challenging part. When it comes to flavor, coffee is very sensitive to air. Any exposed surface area is vulnerable to it. This is why people talk so much about grinding your coffee fresh every time you make it. When you grind coffee most of us think of that as just a step towards getting the precious beverage in your mouth. But it’s a whole lot more than that.
The reason that we grind coffee is so that the water has more surface area from which to extract solids into the solution. If you tried to brew whole beans you would eventually get “coffee” but it would take a long time…a very very long time. Grinding the coffee is essentially exposing exponentially more surface area and this dramatically speeds up the brewing process. But let’s explore it more in regards to air and its effect on flavor.
So, going back to the idea of surface area, once the coffee is ground there are now infinitely more surfaces that air can use to get in there and start diminishing the flavor. Coffees that are pre-ground will go through that peak a whole lot faster- in days instead of weeks- and stale sooner. Makes sense, right?
Now I’m not suggesting anything as dramatic as everyone running out and buying a grinder right now so that their precious coffee doesn’t degrade one more day. When it comes to coffee equipment purchases, a grinder is a bigger ticket item and in order to get the most out of the purchase it is best to do a little research and make an informed decision. For our purposes, I will just say that when you purchase a grinder you will have made a huge impact on the freshness of the flavor of your coffee. If that is important to you then go for it! If not, it can wait.
Whether or not you have a grinder, there are other things that can help prolong the flavor life of your coffee. Regardless of whole bean or ground, we suggest that you find yourself some airtight storage. This one doesn’t have to break the bank either. There are many options out there that work well, including everyday items like canning jars and Ziploc bags, which aren’t perfect but will definitely help. If you want to invest a little into your setup, another great option is an Airscape container. These containers are designed to force excess air out of the container and thoroughly as possible. They aren’t a huge investment, starting around $20.
And to to set yourself up well from the jump? Your easiest control here is buying coffee with transparency on the roast date. If freshness is a factor in your enjoyment of coffee, knowing when a coffee was roasted and paying attention to how it was packaged can help you make a more informed buying decision. In other words, buy the freshest coffee you can find in a sealed valve bag and then you can take on freshness patrol over from there.