Coffee And Espresso Machines Espresso machines use pressure in order to force water into finely ground and tamped beans. They make a rich, tasty brew. Experts at the Good Housekeeping Institute recommend models that brew with the minimum pressure of 9 bars to achieve optimal extraction. Beware of companies that https://www.coffeee.uk/products/swan-retro-espresso-coffee-machine-grey-15-bars