You can't even start to discuss the flavors of espresso when you are using dirty equipment. Every cup will have a distinct taint if the grouphead and portafilter have rancid coffee residue. It is a specially formulated powdered detergent for the heavy residues that accumulate in the espresso machine grouphead, water lines and valves. We sell Cafiza in a tablet form too.
While Cafiza is made to be used with automatic pump machines that can be back-flushed (i.e. they have a 3 way valve), it is an important cleaning solution for ANY espresso machine owner to have. It can be used simply to clean the portafilter and filter basket and to soak any removable part of the machine that is dirty. I use it to clean the tank on my Pavoni, which I then invert the machine to drain. Before cleaning, consult your machine's original instructions.
The 20 oz. bottle should last the home user 6 months to 1 year! Just put a teaspoon in your blank portafilter basket and backflush. I use the powder for other cleaning too, but it is wise to dissolve it first when cleaning parts in order to create a full-strength solution. Do not use Cafiza on aluminum espresso parts, such as aluminum Moka Pots. (You can use them on the Moka Pots we sell; they are all stainless steel).