How to Properly Maintain and Clean an Espresso Coffee Machine Espresso machines force water through the coffee grounds by using pressure. This type of brewing makes an even stronger drink than drip coffee. The machines require 9 bars of pressure to extract flavor from the grounds. Espresso machines are available https://www.coffeee.uk/products/gaggia-ri8425-22-grangaggia-deluxe-rot-premium-coffee-machine