Coffee Data Science
Drying Out an Espresso Shot
An experiment started by a toddler
The other day, my toddler got a chair and started messing around with my superautomatic espresso machine. By the time the machine ran out of water, there were two extra-long shots in one cup. I didn’t want to drink it because it was very diluted, so I thought why not evaporate some of the water?
Why not take some measurements?
It turns out that using a toaster oven to dry out a shot takes too many hours.
A slow film of coffee residue started to form like a lake drying up.
A crust had started to form even before all the water was evaporated.
Data Analysis
I took Total Dissolved Solids (TDS) measurements throughout, and I was expecting the TDS to greatly increase, but it did not. It took some time for it to increase at all. At the end, I had the dry weight of the solids. There was a large error compared to the very first measurement, but that error dropped for subsequent measurements.
I plotted those errors with respect to liquid weight which is backwards in how time progressed for this shot.
I suspect it would have been better to add water than try to evaporate it.
I had gotten too far into the experiment to quit by the time disappointment set in, but it was interesting to see the error between TDS measurement and actual dry solids. I don’t have a good explaination for why the very first measurement was so off. It could have been a measurement error in weight, but I didn’t think to take more than one sample.
If you like, follow me on Twitter and YouTube 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 or Patreon.
Further readings of mine:
Collection of Espresso Articles
A Collection of Work and School Stories
Measuring Coffee Grind Particle Distribution using Image Processing
A Summary of the Staccato Lifestyle
Measuring Coffee Grind Distribution
Espresso Baskets and Related Topics