Coffee and Espresso Machines Espresso machines use pressure in order to make water into finely ground and tamped beans. They create a rich and delicious brew. Experts from the Good Housekeeping Institute recommend models that brew with the minimum pressure of 9 bars in order to achieve optimal extraction. Beware https://coffeee28334.timeblog.net/65628539/10-best-books-on-coffee-machines-espresso