Pulling an espresso is a fine art. It’s also the foundation of any complex coffee, so perfecting this simple shot is perhaps the quickest way of upgrading your barista skills. There are a surprising number of factors that influence the process. You probably already know that the best homemade espresso relies on your ability to temperature surf and about dose, grind size, crema, and extraction. But behind all these factors, there’s another vital component: pressure. Tasting Table couldn’t resist finding the ideal pressure for your espressos, and luckily, coffee expert Andrea Allen, Co-Founder of Onyx Coffee Lab, had plenty of answers.
Onyx Coffee is centered around science, and Allen’s credentials include 2020 U.S. Barista Champ and 2021 World Barista Runner-Up — needless to say, she spilled the beans. “High pressure is the hallmark of the espresso brew method,” Allen explains, “Standard is nine bars of pressure, but many baristas and also espresso machine manufacturers have utilized lower pressures, ramp up or ramp down, as an element of the recipe to create nuance and soften the extraction process and time. But nine bars is standard.”
What difference does pressure make?
Poor pressure is one of the biggest mistakes you need to avoid when making espresso at home. Let’s put this bluntly: Pressure is the glue that holds an exceptional espresso together. Too little creates a weak-tasting drizzle; too much extracts so much from the grinds that it causes bitterness. In all honesty? Neither is ideal. The key to creating a perfect shot of espresso is finding that middle ground — even if you play around with softer finishes later. Whether you’re learning how to drink espresso like an Italian pro or just hosting a casual brunch, abide by Allen’s advice and start with adjustment nuts at nine bars of pressure.
Sometimes, it’s not as simple as adjusting a dial. Every machine is different, and certain brands won’t have easily accessible pressure settings; Nespresso doesn’t even let you adjust the temperature. In this scenario, adequate maintenance and usage become of utmost importance. For instance, Nespresso machines all guarantee up to 19 bars of pressure, but this can be sabotaged by issues like airlock. Be wary of running cycles without sufficiently filling the water reservoir — it’s a recipe for disaster, unleashing havoc-causing air into your machine’s system.
