Making espresso is sometimes considered an art, with countless variables to play around with. Different techniques and a large number of different results that can be obtained with the same coffee.
Traditionally, espresso is brewed at a pressure of 9 bar, which is maintained throughout the brewing process. This means that as soon as you insert the portafilter into the machine and press "start", the pump turns on and pushes the coffee at full force throughout the extraction.
This ensures that the coffee is brewed evenly: the same pressure is applied to the coffee throughout the entire process. Uniformity is one of the most important indicators of good extraction, because it means that all of the coffee is participating in the entire brewing process, and generally results in a balanced and well-extracted cup.
However, a consistent pressure is not the only factor for a consistent extraction. A pressure of 9 bar is a tremendous force - nine times the pressure of our atmosphere - and this violent water jet can cause its own problems. If the coffee puck has not been properly prepared, air pockets, cracks or varying densities can develop in the coffee bed. Water can pass right through these weak spots, leading one to what is known as channeling. The water that flows through a crack does not come into contact with all of the coffee, resulting in uneven extraction despite the even pressure.
One solution that baristas have been using since machines began allowing more and more precise control over extraction and brewing profiles is what is known as preinfusion. This starts the brewing process at a lower pressure, which is slowly increased as the extraction progresses until the full pressure of 9 bar is reached.
This gentle start helps to ensure that all the coffee is evenly saturated before the pressure is increased. In this way, the water slowly penetrates the coffee, eliminating irregularities in the puck and creating a homogeneous, well-saturated coffee bed through which the water then flows evenly.
To achieve this, some sophisticated tools are required. Some machines have a paddle or lever that allows the barista to manually control the pressure in the group head during the brewing process. Machines that are designed for high volume and where it is too time consuming to control each shot may have electronically programmed preinfusion profiles where the machine automatically controls the pressure. If you only have an on/off button, you can achieve a type of preinfusion by simply peeling off the pump for a moment after the first few seconds of extraction.
A well executed preinfusion can help improve the uniformity of an espresso, which not only results in a more balanced coffee flavor, but also allows for a higher extraction overall. This allows us to extract more flavor from the coffee and better showcase its natural characteristics without over-extracting or unbalancing the coffee.
Want to dive deeper into how to make espresso? We offer barista courses for professionals and amateur baristas, where you can learn about the full range of espresso. Find out more here.
Hallo lieber Tony,
vielen dank für deine freundliche Bewertung - gerne helfen wir weiter: du kannst, in dem du den Finger auf das Display legst, über die Seite scrollen. So bewegt sich der Text und du kannst alles lesen, was vielleicht kurzzeitig vom Button verdeckt wird.
Solltest du weitere Fragen haben - gerne auch zu Kaffees, helfen wir dir jederzeit gerne weiter.
Happy Brewing,
dein 19grams Team
It says 5 stars but you cannot rate this abo at all. I'm dissapointed because I get same coffee again and again and I don't like it at all. Even cheapest Spig Blume roast mix is better. Sure maybe it's not my cup of tea but could you send just different once. I ordered cofee once in two weeks so it's not even very short time. I wouldn't recommend this abonemet.
ich habe eine Box (knapp100€ mit 1,2kg Bohnen) als Geschenk bestellt
gesendet wurde eine Box für 50 € mit 250g Kaffee und 2 Tassen ...
ich warte aktuell noch auf Rückmeldung vom Kundenservice , den werde ich dann extra bewerten .
aufgrund des bestellverlaufs bisher kann ich absolut keine Empfehlung aussprechen!
So disappointing this year. We have ordered the advent calendar for years now (and paid for shipping to the US - that's how much we liked them) but this year was a complete disappointment. Many of the tins had stale beans in them - they even smelled staled right when opening them. Very few nuances and just plain boring coffees. There were a few highlights sprinkled throughout but nothing worth writing home about. Honestly, I am looking forward to returning to my regular coffee. I won't be ordering this calendar again next year sadly.
Dank anaerober Aufbereitung bietet der Kaffee ein üppiges Aromaspektrum, beginnend mit ausgeprägten Fruchtnoten und gefolgt von Schokoaromen. Für diesen Kaffee muss man sich - auch in der Zubereitung - etwas Zeit nehmen. Er ist definitiv kein Alltagskaffee. Dafür ist er auch zu hochpreisig.