Coffee and Espresso Machines Espresso machines use pressure to push water into finely roasted and tamped beans. They make a rich and delicious cup of coffee. Experts from the Good Housekeeping Institute recommend models that brew at the minimum pressure of 9 bars in order to get the best extraction. https://wwwcoffeeeuk73731.blogdomago.com/29077055/what-is-coffee-machines-espresso-and-why-is-everyone-talking-about-it