Coffee and Espresso Machines Espresso machines use pressure to force water through finely ground and tamped coffee 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 achieve optimal extraction. Beware of https://www.coffeee.uk/products/breville-cafe-roma-espresso-machine-brushed-stainless