Like me, if you're not in the professional coffee sphere, then you wouldn't have come across this fact, well let's look at this Rule:
It's a specialty coffee guideline designed to maximize flavor and freshness.
It outlines three critical timeframes:
15 Months: Green, unroasted coffee beans should be stored correctly for a longer use by date; ideally in air tight one way valve containers, and in a dark environment.
15 Days: Most Roasted coffee beans are at their peak flavour; some may take far longer to peak!
15 Minutes: Ground coffee should be brewed immediately, and only grind what you need per brew!
The Breakdown
Unroasted Beans (15 months): Green coffee is shelf-stable, but its delicate natural sugars and acids begin to degrade past the 15-month mark, resulting in a flatter flavour.
Roasted Beans (15 days): After roasting, coffee undergoes a resting process where it releases carbon dioxide (degassing). It hits its "sweet spot" of peak flavour, natural oils, and aromatics within the first 15 days.
Grounds (15 minutes): Once beans are ground, their surface area is massively exposed to oxygen. Within 15 minutes, the oxidation process breaks down delicate compounds, rapidly causing the coffee to lose its rich aroma and vibrant tasting notes.
