The 15-15-15 Rule You Need To Follow For The Freshest Coffee

Dedicated coffee enthusiasts know the daily joy of drinking the freshest, best-quality cup of coffee possible. To share secrets about how the freshest coffee is produced, Matt Killen, co-owner and Principal Roaster at IMUA Coffee Roasters in Kauai, spoke exclusively with Chowhound about the 15-15-15 rule.

The 15-15-15 rule, also called the Rule of 15s, is a three-part timeline designed to guarantee you have the freshest beans and most flavorful cup of coffee possible. A quality coffee roaster may follow the Rule of 15s by instinct. "While I'm not intentionally adhering to the rule, I do practically end up doing so," Killen told us.

Breaking it down, the Rule of 15s suggests the optimal timing for the stages of coffee bean production from harvest to roast, roasting date to use date, and time between grinding to brewing. Freshly picked green coffee beans can be stored for 15 months and still retain freshness, as raw beans don't decay rapidly. If you're wondering how long coffee beans will last once they're roasted, they will retain optimal flavor for about 15 days. Finally, brewing coffee within 15 minutes of grinding it will produce the most flavorful cup. Brewing it right away is even better. As Killen explained, "We only grind for our cafe prior to immediate use." Coffee from some of the best coffee roasters in America will likely be fresher than coffee from a large chain brand. "If a customer is purchasing from a small roastery, it's almost guaranteed that their product will be adhering to the Rule of 15s, whether intentionally or not," Killen said.

Coffee beans produced using the Rule of 15s will guarantee you have the freshest beans right from the store; however, you also need to store them properly at home. "Ideally, an airtight container will keep beans fresher longer, and whole beans are the ideal for storage," Matt Killen suggested. Oxygen and light degrade the oils and sugars in coffee beans, so opaque, airtight containers keep it fresher. Since whole beans have less surface area than ground coffee, they're less prone to react with oxygen. Still, be strategic with your bean purchase. "Buy what you're going to use; you're better off getting beans more often than getting larger quantities that get consumed slowly," Killen said.

However, while you might think a special container is necessary, the best way to store coffee might be the easiest. The original bag is fine as long as it has a one-way degassing valve, which prevents oxygen and moisture from getting in and also releases carbon dioxide. 

While fresh beans are the foundation of an excellent brew, also consider some of Alton Brown's special techniques for unforgettable coffee: Use filtered or bottled water for the cleanest flavor, and heat water to just below boiling temperature to extract optimal flavors from the grind. In addition, use a ratio of 1 gram of coffee to between 14-17 grams of water, depending on your brewing method. These secrets will help you brew a cup of coffee that will enliven your morning.