The brewing process to create espresso coffee begins with grinding the coffee to the right texture, not too coarse and not too powdery. It must be ground to a texture that feels slightly gritty if rubbed between your fingers, but sufficiently fine so it can be packed down into the filter basket, creating a compact and firm base so water cannot quickly fall through the grinds, but instead filters slowly through to absorb and deposit the flavors from the ground beans. If the water is allowed to fall through the grinds too quickly, the flavor becomes watery and very light tasting. A true espresso will produce a somewhat syrupy texture with a rich, strong flavor.
The process used for brewing involves pressure rather than a gravity drip of water like traditional coffee brewing. Water for espresso is heated under pressure and forced slowly through the grounds packed in the filter basket, circulating throughout all of the grinds rather than only down through the center of the basket. This process insures a stronger more flavorful coffee with a deeper and richer taste.
USDA Nutrition Facts