Coffee and Espresso Machines Espresso machines utilize pressure in order to press water into finely crushed and tamped beans. They create a rich and tasty brew. Experts from the Good Housekeeping Institute recommend models that brew at a minimum pressure of 9 bars in order to get the best extraction. https://coffeeeuk47372.blogtov.com/10248693/espresso-machine-explained-in-fewer-than-140-characters