I know it seems obvious but simply cleaning your espresso machine every night will improve the taste of your coffee. A dirty machine will give a bitter taste to your coffee. Every time you make an espresso, the oils released build up on the filter basket and group handle.
Without cleaning your machine you are in effect serving coffee in a dirty cup (something I am sure you would never contemplate doing). Your machine can never be too clean. We are UK distributors of Urnex Cafiza, Grindz and Rinza coffee cleaning products. Urnex have now been in business for 75 years, supplying first New York and now the world with the finest espresso machine cleaning products.