Coffee and Espresso Machines Espresso machines use pressure to force water through finely ground and tamped coffee beans. They make a rich, delicious brew. Experts at the Good Housekeeping Institute recommend models that brew at the minimum pressure of 9 bars in order to get the most efficient extraction. Beware https://coffeee14613.iyublog.com/29298477/espresso-machine-explained-in-fewer-than-140-characters