Coffee and Espresso Machines Espresso machines use pressure to push water through finely ground and tamped coffee beans. They create a rich and flavorful brew. Good Housekeeping Institute experts recommend models that use a minimum of 9 bars to ensure an ideal extraction. Beware of manufacturers who claim to use https://www.coffeee.uk/products/quest-36569-espresso-machine-with-milk-frother-15-bars-pressure