Degassing and “the freshest coffee you can get”

There’s a new trend in the world of specialty coffee. Roasters are advertising their coffee as “the freshest coffee you can get.” They will say this along with marketing language like “same day roasting” or “delivered at peak freshness” or “still hot off the roaster". It’s infuriating.

Why?

Cause it’s all a ruse to trick people that don’t know a lot about coffee into thinking their coffee is better than others because it is “fresher”.

… and it’s a dirty trick.

Any roaster, if they’re being honest, will tell you that coffee that has just dropped and cooled from the roasting machine doesn’t actually smell like coffee. In reality, it smells like somewhere between nothing and burnt popcorn depending on the roast level.

See, coffee is, in some ways, a bit like a steak in that it needs to be rested after cooking. But instead of needing to rest to lock in moisture, roasted coffee needs to go through a process called “degassing”. I know. It’s a funny word.

Coffee beans have two things locked inside of them that need to be released: Water and Carbon Dioxide. During the roasting process, the beans go first through a drying phase where the outside of the bean loses moisture and later it goes through a stage called First Crack where the heat causes the moisture inside of the beans to essentially boil and create steam pressure which eventually cracks open the inside of the bean and escapes. The beans generally all do this around the same point in the roast and it sounds like popcorn popping. When you roast into dark roast territory, there is another point in the roast called Second Crack, which is a similar idea but it is CO2 releasing instead of moisture. The sound is much softer and sounds like pouring milk over rice krispies.

Once the coffee is done roasting, there is still CO2 trapped inside the beans that will slowly release over time. For darker roasts that went past second crack, much of the CO2 has already released and the degassing time is less, around 2-4 days. But light and medium roasts that didn’t make it that far need longer. Anywhere from 5 days up to 2 weeks for really light roasts. While the coffee is degassing, it is also developing all the flavors and aromas that people associate with coffee.

That being said, unless you’re buying a french roast, chances are likely that when you are buying coffee from a small batch roaster, the coffee is still degassing. Most local roasters will put roast dates on the bags to give you an idea when the coffee will hit peak freshness which, I can confidently say, is NOT a day or two after roasting.

So what does this mean for you?

This knowledge puts power in your hands when you’re buying coffee. One thing to ALWAYS look for on a bag of coffee is called a one-way release valve.

The function of these is to allow CO2 to escape out of the bag without letting oxygen and moisture in. If you see a bag of coffee without one of these, it most likely means the coffee inside is not fresh enough for the producer to need the valve. If the coffee is fresh and the bag does not have a valve, the CO2 will expand the bag, possibly even to a point where it will burst open.

SO DON’T BE FOOLED!

Always look for a roast date and don’t let a roaster tell you that day-of or day-after is the best way to drink your coffee!