How Coffee Works

The beans are roasted to perfection and have been poured into a cooling tray. Now what? If roasting is an art, brewing is a symphony. Four factors have to come together to make a perfect cup: the freshness of the coffee, the grind, the proportion of coffee to water, and the water itself.

Freshness

Coffee needs to be kept away from light, heat and moisture. Oxygen will speed its deterioration, so store roasted beans in an airtight container and keep it in a cool, dry place for up to two weeks. Since ground coffee begins to lose flavor quickly, coffee should be ground only in the quantities needed for a few days. Refrigerate ground coffee to keep it from going stale -- even then, it's only fresh for two weeks or so.

Grind

The whole point of grinding coffee is to get the most flavor out of the bean. To ensure the best-tasting coffee, buy the beans of your choice and grind them yourself just before brewing. Coffee grinders are inexpensive, widely available machines.

Generally, the faster the brew time, the finer the coffee grind. Espresso, which is brewed in about 25 seconds, has a very fine grind, almost like powdered sugar. A coffee press takes about four minutes and uses a coarser grind than espresso. American drip coffee is coarser still -- it can take anywhere from five to ten minutes to brew coffee using a standard coffee maker.

Now that we understand the importance of freshness and just the right grind, let's take a look at how measurement and water factor in a good cup of coffee.