Tamping

Tamping is the process of leveling and pressing down ground coffee inside the portafilter basket before brewing espresso, using a heavy, flat-bottomed tool called a tamper. The goal is to create a uniform, compact bed of coffee so that hot, pressurized water flows through it evenly, extracting all the best flavors instead of finding the path of least resistance through cracks. This proper resistance ensures that water stays in contact with the coffee for just the right amount of time to control extraction (the process of dissolving flavors). A loose or unevenly pressed coffee bed leads to a watery and thin espresso. Modern baristas know that pushing straight and keeping the tamper perfectly level is far more important than using sheer muscle strength.