Portafilter for espresso machines

Brewing sieves are made of stainless steel and are usually available in two sizes: for one cup (intake of ground coffee: 6-7 grams) or two cups (corresponding double intake). There are also brew sieves for 3 cups of coffee. A diameter of 58 mm and a uniform fastening of the sieve in the portafilter by means of a spring are common in gastronomy. The sieve with the pressed coffee grounds is held by the sieve holder and attached to the brew group. The portafilter serves two functions: it presses the brewing sieve against the brewing head seal and directs the finished espresso that runs out of the sieve into the cup (s) below. However, if grinding and pressing have been carried out correctly beforehand, the latter function can be dispensed with in favor of a sieve without an outlet connection, namely a bottomless portafilter. Bottomless portafilter are actually just a ring with a handle and have many advantages such as a shorter heating-up time due to less mass, easier cleaning on both sides and visual inspection. There is also no need for a press-on station, since laying on the table edge is sufficient. However, a division into two cups is not possible. Also on this page you will find so-called blind screens, which however have no holes and are therefore not really screens. They are also not used for coffee preparation, but for cleaning purposes, namely the so-called "backwashing" - a special process that is used in high-quality machines with a solenoid valve, in particular to clean the brewing head and shower strainer. For this purpose, like the brewing sieves, they are placed in the portafilter.