Interesting concept - I used this method off and on with some of my first machines but for a different reason. I started with a Krups machine that uses pressurized double bottom baskets with a pinhole exit. I feared clogging the filter with fines so I used a Presto MyPod for Senseo filter - these are something like $1.50 per pack direct from Presto. I never could tell a taste difference but cleanup was easier. The Krups is 53 - 54mm but the bottom didn't run holes out to the edge of the filter basket so a perfect fit wasn't required but this paper was close to perfect anyway. Might be of use to those with a 50 - 53mm basket.

Gary, thanks for reporting on the hole punch. That device looked attractive to a very lazy person I know (ehm) who doesn't filter his espresso much any more.

An interesting thread.

I've been running lab tests between Italian Press (70 micron screens) vs. Pour over with Chemex filters to refute the whole idea that pour-overs produce a superior cup of coffee through measuring organic dissolved particulate to supplement blind cupping.

I can share with you now that paper filters, whether washed or dry, bleached or not, strip out a significant amount of organic material. Enough so, I'd say even a hobby coffee drinker would be able to taste the difference.

How that plays out here is that paper filters are removing organic material, significant amounts of it. The two components in this thread behave like all water soluble materials. Knowing that they are fat based, they are attracted to wood fibers. Using 9 bars of pressure will certainly move more parts past the filter, but the filter will still pull oil and other particulates out. Less pressure, more trapped materials.

New evidence supports roasting prior to second crack to reduces caffeine and acid; further, extracting coffee through the cold toddy method minimizes the extraction of these volatile compounds. This is good news for people with little tolerance for caffeine/acid/bitterness.

Technically, today, you can make for yourself a very low volatile cup of coffee without having to use paper to rob flavor from your cup!

Sounds like you're really craving the goodness of espresso, God bless you for that.

I was offering an alternate to espresso with the roast profile combined with cold toddy. I do it in the shop for customers with any "volatile" organic compound sensitivity, including cafestol and kahweol. Those compounds want time and heat to dissolve. Cold toddy gives the time aspect, but it does little good with water that is less than 68ish degrees. That temperature doesn't provide the catalyst. The result is an uncommonly smooth coffee.

The best part is that you can take the coffee and steam-wand it and it very much tastes like an Americano. I've done countless blind sampling with customers and to date all of them have preferred cold toddy coffee steamed over our Italian pressed coffee using the same beans... Most people think you're pulling a parlor trick on them, then they just start asking for it that way.

On days when you crave something in addition to espresso, consider this.

Cheers

I have been using aeropress filters in my portafilter for several weeks and have been very happy with the results. I just decided to do a search to see if others had tried it - and found this thread.

My measuring tool is my thumbs - my thumbs hurt in the joints when I drink espresso and I'm a musician so the stiffness in my thumbs was a big deal. I stopped drinking espresso (stopped all coffee) and thumbs returned to normal after about 2-3 days without coffee. I've gone back to espresso and thumb pain returned - quit and pain went away. This cycle has repeated itself many times over the past year as I've stayed away from coffee for a month or so and then found myself unable to resist the call for an espresso.

Since I've been using the Aeropress filters in my portafilter the thumbs have no pain.

No idea which substance my thumbs are sensitive to, but whatever it is the paper filters are catching it.

I've actually thought about adding a paper filter to an espresso machine before, just because I don't like the fine (bitter over extracted) particles that seem to end up in the crema.
I haven't tried it yet, I was afraid the filter would either be torn apart by pressure or it would clog the machine (with a 3 way selenoid machine I don't think that's too much an issue though) I remember I read somewhere that high cholesterol isn't actually related to heart disease. So I don't really worry about that. Eating healthy, 7-9 hours of sleep a night, some exercise and not getting too stressed is a good idea.