Coffee Data Science

Counting Fines in a Cup of Espresso

Trying to measure small things

Robert McKeon Aloe
Nerd For Tech


When discussing coffee and the theory of fines migration, often people talk about the amount of coffee grounds that end up in the cup. I wanted to measure this variable, and a recent experiment with forced fines migration made me think I could measure it.

So first, I pulled a shot, a long shot. Most of my shots are short, but I wanted to maximum how many grounds ended up in the cup. I ended up with a 3:1 shot.

Then I let the shot cool down, and the particles will settle on the bottom. Afterwards, I used a turkey baster to carefully remove the water on the top.

Then I added water back into the cup. The trick with being able to see the coffee grounds is to isolate them in color from the liquid coffee. I repeated this process once more to get to a light enough color liquid.

Round 1 and 2 of diluting the solution

Then I was able to spy the particles at the bottom. There definitely were some, but the amount is less than 0.01g. I have a video showing the particles swirling in solution.

Here is am image of the bottom of the cup.

Coffee grounds do end up in the cup during an espresso shot, but the amount is not sizable. I am sure some may still be suspended in the liquid coffee, and more study and experimentation needs to be done to show they significantly impact taste. This experiment is easy to replicate.

If you like, follow me on Twitter, YouTube, and Instagram where I post videos of espresso shots on different machines and espresso related stuff. You can also find me on LinkedIn. You can also follow me on Medium and Subscribe.

Further readings of mine:

My Future Book

My Links

Collection of Espresso Articles

A Collection of Work and School Stories



Robert McKeon Aloe
Nerd For Tech

I’m in love with my Wife, my Kids, Espresso, Data Science, tomatoes, cooking, engineering, talking, family, Paris, and Italy, not necessarily in that order.