I don’t know about you but I’m dumb. So whenever possible I try to simplify my view of the world. Because the world is complicated and thinking about complicated things hurts my head. I don’t want to deal with that.
I kinda realized that all of this pressure profiling voodoo is getting over my head. There is so much choice. The possibilities are endless. I hate it. I need to simplify.
Types of pressure profiles
I found this very interesting video comparing three pressure profiles and their influence on the taste of the resulting espresso shot. They’re comparing three shots:
- A classic flat profile
- A lever machine style shot
- A flow profile
The interesting part is that these three profiles mark extrema points in the n-dimensional space of madness that is pressure profiles. In plain English: They are very different from each other and create very distinct flavors.
Actually 1 and 2 are like “opposites” in terms of flavor, while 3 sits in between them. We’ve just reduced the size of the variable pressure profile from endless in several dimensions to three possibilities in one dimension. Very nice. Let’s talk about these profiles then.
1. Flat profile
“Flat” in this context refers to the pressure curve of the profile. It keeps the pressure constant at, say, 9 bar. The flow is adapted to hold this pressure until the shot ends.
I called it classic because that’s what “classic” espresso machines do. They pump as much water as they can against the puck. The over-pressure valve opens at X bar, effectively limiting the pressure.
The flavor of flat profile shots is the opposite of flat. Isn’t that funny? Or have I just gone mad? Anyways, the flavor is “spiky”, in the sense of a lot of acidity and bitterness while the body is less pronounced.
2. Lever machine
Lever machines were the first espresso machines that existed. They were first sold by a guy called “Gaggia” by the way. Their functioning is simple: There’s a chamber filled with hot water. A piston with a huge lever can be used to a