Filter holders for espresso machines can be divided into two main categories: bottomless ones and standard ones.
Standard filter holders, also called "closed-bottom," have a solid bottom on which the coffee powder rests. The advantage of these portafilters is that they allow for greater pressure during coffee extraction, which can lead to a higher brew and thus a stronger flavor. However, just the higher pressure can also result in higher moisture in the coffee, which can cause a loss of flavor.
Not surprisingly, as a result, bottomless portafilters are the preferred choice of coffee professionals.
Also called "open-bottomed," these portafilters do not have a solid bottom, with the coffee then going to rest on a metal grid.
It is precisely the absence of a solid bottom that allows for the creation of less pressure during coffee extraction, which can lead to a milder flavor and more intense aroma. However, the experienced operator will always have to keep a very close eye on the levels: in fact, excessively low pressure can also cause a lower extraction and thus a weaker flavor.
In general, bottomless portafilters are considered more suitable for higher quality coffee, while standard portafilters are perfect for brewing regular coffee. Of course, it should be remembered that the choice always depends on individual preferences and the specific needs of the coffee you wish to prepare.
In any case, the use of a well-cleaned and well-maintained portafilter is critical to achieving quality coffee, so cleanliness and hygiene always come first.
One of the advantages of bottomless filter holders is that they are easier to clean than standard ones: because there is no solid bottom, it is easier to remove coffee residue from the filter holder. In addition, the absence of a solid surface on the bottom greatly reduces the likelihood of bacteria and mold growth, which in turn reduces the risk of coffee contamination.
However, bottomless filter holders are also more delicate than standard ones and require more care during use. For example, it is important to avoid damaging the metal grid on which the coffee rests, as if damaged it can affect the quality of the coffee.
Cleaning an espresso machine is therefore essential for making good coffee, and if you want to learn more you can read our dedicated in-depth article and find out how to drain the water from your lever espresso machine.
It should also be mentioned that bottomless portafilters are generally more expensive than standard ones, although many users believe that the higher cost is justified by the superior quality of coffee that can be obtained with their use.
In conclusion, bottomless and standard filter holders both have their advantages and disadvantages. The choice depends on individual preferences and the specific requirements of the coffee you want to brew. In any case, the use of a well-cleaned and well-maintained portafilter is critical to achieving quality coffee.