Operation Manual
43
Too Fast
Here we see a flow of
espresso that is issuing forth too
quickly. The flow seen here be-
gan almost immediately, lacked
viscosity (it is thin and watery),
and was spraying espresso all
over the counter. Notice that the
color of the stream is quite light
in color. The spraying jets are
not noticeable with the original
portafilter included with the DD,
but the fast flow and light color
certainly will be. The espresso
will lack body (will be like water
on the palate). These are all signs
of under-extraction. Causes of
under extraction can include:
• Too coarse of a grind. Set your grinder to a finer grind. How much finer? It depends on the grinder itself. As
each brand works differently you will need to experiment to learn just how much to change the grind. The
faster the flow the more the grinder will need to be adjusted towards a finer setting.
• Channeling. This is usually caused either by improper distribution of the coffee before tamping. The coffee
may have been dosed with voids (air pockets) in the mass of grounds. The force of the water can bypass
much of the coffee, flowing through the path of least resistance without extracting the rest of the coffee
properly.
• Under-dosing. There was not enough coffee in the basket and so there was not enough resistance to the flow
of water.
• Over-Dosing. Using too much coffee can cause the compacted coffee to hit the shower screen when insert-
ing the portafilter into the group. This disturbs the coffee causing cracks in the compacted mass before
extraction begins.
• Faulty basket. If a basket develops a crack it can flex open under brew pressure and allow the puck to be
damaged causing a fast flow. If this is suspected, examine the area on the floor of the basket around the outer
perimeter of the perforations which is where most cracks occur. This is a rare occurrence in home use.