Coffee and Espresso Machines Espresso machines make use of pressure to make water into finely ground and tamped beans. They create a rich and tasty brew. Experts from the Good Housekeeping Institute recommend models that brew with a minimum pressure of 9 bars in order to ensure the highest extraction. https://www.coffeee.uk/products/gaggia-manual-espresso-cappuccino-machine-with-magnet-valve