We already have one coffee+Cholesterol thread here, and I REALLY wish this thread will ONLY cover the espresso part, not the health part. Please help make my wish come true.
So, this thread is about: 1. how to make decent paper-filtered espresso? and 2. whether it reduces Cafestol/Kahweol or not? While still wondering about the second question, I started with the answer for the first question. Now to the process & photos:
First I took a new Aeropress filter and cut it to cover the perforated area of a Synesso double basket:

Then ground some 15g on my Versalab right on top of the filter:

Next is a photo of the last third of the pour. I line-pressure-pre-infused for about 5s then jumped to 8+bar. Handling the phone(camera) overwhelmed me and I didn't catch much of the first part of the pour. I don't know if it channeled in the beginning or not:

The shot started all-crema and slowly stabilized, just like regular shots. The crema was much denser than on regular shots, probably because the paper filter bursts any bubbles:

The basket bottom/holes were unusually clean, understandably so:

The paper filter was quite saturated before cleaning...

..and remained so even after washing with warm water, see contrast to a cleaner one:

Crema persisted even after after all the cleaning, photographing, etc, maybe 5 minutes after the pour:

The taste was shocking, it didn't taste "filtered" as I anticipated, but like it was slightly underextracted! The temp/grind was right on but it could be that the shot channeled, or that the filter absorbed most of the bitters and the shot leaned too much to the sours.
I'm not sure what to make of that. but more importantly, I have no idea and no way of knowing if this reduces Cafestol/Kahweol or not.
Washing and reusing the filters doesn't look like a good option given how discolored they are after cleaning. Cutting a fresh filter for every shot with scissors is a pain. I haven't decided where to go from here yet, but at least this filtering business doesn't produce undrinkable espresso.
Hope you enjoyed this enough to give it a shot and share your experience.
EDIT: just a little update, more paper-filtered shots confirm the channeling possibility on that first one. All subsequent shots were much more balanced...makes me suspicious if there is anything filtered?




