If brewing drip coffee is an art form, then pulling a good espresso shot is an act of exquisite grace combined with scientific application. There are, after all, worldwide barista championships that are based on making the perfect espresso. Making a good espresso is a task of constantly evaluating grind size, temperature, and brew time to deliver perfect and consistent espresso shots.

Making a shot boils down to grinding the beans, dosing the grind, tamping the grind into a puck or pellet in the portafilter, and pushing hot water through the puck with pressure. At every step care must be taken to ensure that the espresso is treated appropriately. An incorrect grind can affect the brew time and therefore the taste; not tamping properly will create channels that funnel the water, resulting in poor extraction.

Learning the finesse to generate a perfect pull requires training, study and practice. Here are a few tips for reference:

¨      Beans begin going stale the second they are ground. To ensure the freshest taste, only grind the amount of beans needed right before brewing the espresso.

¨      Constant temperature is a key component to a good espresso pull. To achieve this, always keep the portafilters locked in the group heads so they stay hot. Warm the shot glasses as well with hot water right before brewing the espresso.

¨      A buildup of coffee oils will affect the quality of the espresso shot. To maintain pristine taste, keep the portafilters clean and wipe down the group heads.

¨      The grind size of the espresso is another key component to quality shots. The grind size affects the amount of extraction due to exposed surface area and the amount of time it takes for water to pass through. Constantly monitor the grind size of the grinder and adjust as necessary.

¨      The water’s ability to pass through the puck will directly affect taste and quality. Openings between the grinds will affect extraction by giving water a channel to pass through. Conversely, a puck that is packed too tightly will not allow enough water to pass through. Always tamp the ground espresso with 25-30 pounds of pressure, being careful to distribute the pressure evenly around the portafilter.

¨      Never lock the portafilter into the group head without brushing away loose grounds on the portafilter’s rim.

¨      Brew time should run between 25-30 seconds for a 1.5 ounce shot (this may vary based on the espresso machine manufacturer/model. Check with your distributor about ideal brew times for your machine.). Brew times that are outside of this range suggest that something went wrong in the preparation and needs to be adjusted. A short brew time, for instance, could be indicative that the grind was too course, that not enough coffee was used, or that the grinds were not tamped with enough pressure. The reverse holds true for long brew times. You should only work with one factor at a time, though; changing too many variables will make it more difficult to troubleshoot.

A good shot will end with a light tan color that is characterized as “blond.” The crema, or foam that tops the shot, should be thick and dense. It is the signature of a good pull, and it acts to seal in the aroma and flavor of the espresso. The shot should taste balanced and possibly sweet … never harsh, bitter, or weak.