Coffee is at its peak flavor potential between two and fifteen days after it’s been roasted. Try to buy your coffee as close to its roasted-on date as possible. If you have the good fortune of getting your coffee the day it was roasted (like the people who pick it up straight from our store), wait at least 24 hours before you brew it. The roasting process causes carbon dioxide to build up inside the coffee beans which needs some time to escape the bean. Otherwise, that CO2 will interfere with the grind and impart some bitter into your cup. Waiting too long to drink your coffee will also negatively affect your coffee’s flavor. Why? Oxidation and decay. After that CO2 exits the beans, oxygen makes its way inside, which leeches off good-tasting materials. After a short time (just over the fifteen-day mark), you’ll have noticeably less flavor complexity in your cup. After six months (or a year), you’ll experience only awful bitter wood flavors. There’s just nothing good left in the beans.