The 15-15-15 Rule For The Freshest Coffee Possible

Stale coffee will get the job done in the most technical sense since it won't have lost any of its caffeine, but it will smell and taste like cardboard and that can't be worth the energy boost the coffee provides. If you've moved beyond buying instant coffee and you're starting to grind or even roast your own beans (you can roast coffee beans in an air fryer), then it helps to know some basics about how coffee beans work and how long they'll stay fresh. A good rule of thumb to help keep your coffee fresh is something that baristas call the 15-15-15 rule.

The 15-15-15 rule refers to the different stages of a coffee bean's life before you drink it. Green and unroasted coffee beans should be roasted within 15 months of harvest, roasted coffee beans are best used within 15 days, and coffee grounds should be brewed within 15 minutes. Freshly ground coffee always tastes better, but the time it tastes best is a window which can shut quickly. A variation of the 15-15-15 rule leaves out the first part about unroasted coffee beans (you're less likely to be working with those) and adds that you should drink freshly brewed coffee within 15 minutes. When we say "should" in all these cases, it doesn't mean you have to; this is just when it'll taste its absolute best.

While it's a bit general, the 15-15-15 rule tends to hold true at each stage. The major difference between green coffee beans and the regular kind is that green beans are raw, but plenty of people buy them like this so they can roast them themselves. In their natural state, raw coffee beans are relatively shelf stable. As long as they're kept away from sunlight in a sealed container or bag (to keep mold away), you can expect them to last at least a year. Keep in mind that some time will have passed between their being harvested and you buying the beans, which can impact how long you should expect them to stay fresh.

Once roasted, the timer starts running as the oils and flavor compounds inside coffee beans become vulnerable to oxygen. Their flavor will begin to fade after a couple of weeks. To keep them fresh longer, store the beans in an airtight container as the packaging which coffee beans are sold in often do a poor job of keeping them fresh. Freezing coffee beans can also help them last longer, although it's a bit of a hassle. Once ground, coffee loses flavor even faster. While it's fine to buy grounds and keep them for a few weeks, the flavor simply won't stay as strong (there's a reason coffee snobs like to grind the beans themselves). Once brewed, wait for it to cool and drink it quickly.