When you walk into Van Dyke Coffee there is one thing that sticks out, our coffee roaster. We proudly display ours in the middle of the shop because it symbolizes something we take very serious, fresh coffee. You will see dates on each one of our tubs of coffee as well as on each one of the bags we sell. This is something that we care about.
Coffee is not like wine which increases in desirability as it ages. The life span of good coffee actually last from about two days to about two weeks after it is roasted. The main reason for these dates is due to the gasses in the coffee. When coffee is roasted it stores up carbon dioxide within the bean which releases as it ages.
If you have ever seen us do a pour over at the shop you will notice that our coffee "blooms" (or expands) as the first amount of water touches the ground coffee. This is the carbon dioxide leaving the coffee and making room for the water to extract the flavors. If you do an experiment with coffee that is from a grocery store that has been pre-ground you will notice that there is little to no bloom. There is no carbon dioxide left, this is when we call coffee stale.
While this is some pretty cool science, why does it even matter?
Let's do an experiment with that last little bit of beans you have which was roasted two months ago. If we brew it up next to the fresh batch of beans roasted last week we will notice something staggering. The beans may be from the exact same bag of green beans and both roasted to perfection and yet they taste completely different. The two month old beans are flat and lacking flavor while the new beans are vibrant and exploding with great coffee flavor. There still may be some flavors in the two month old coffee but they are muted and a shell of what they once were.
Now that we have finished our experiment, let's look at the other end of the spectrum. What happens if the coffee is too fresh? If coffee goes bad after a few weeks, doesn't that mean it is best minutes after the roasting process is complete? Nope, sorry. The main theme of this freshness talk has been carbon dioxide, and it is the culprit for this as well. When grinding up a coffee that we roasted less than two weeks ago there is actually too much carbon dioxide in the beans. This produces a grassy or hay flavor that is undesirable in a cup of joe. We have found that 2-14 days is the ideal for our coffee and we strive to serve every cup that way.
So when you are looking to buy coffee from anyplace, be sure to check the roast date on the bag. It can make the difference between a good cup and a great cup of coffee.