I’ve been collecting data on my shots for almost 2 years. I wanted to look through that information to see if I could see any trends, particularly the age of a roast. The main caveats are:

1. My methods have improved over time.
2. My tastes have changed.
3. My tasting palate has expanded.

So I normalized the data to give a fairer comparison. I found taste and extraction improved over time up to 5 weeks post-roast. I did not find a taste drop off past three weeks, which is what is typically suggested by roasters. However, I don’t have too much data past 5 weeks because my roasts are usually around 1 lbs in weight and I drink too much espresso to have a roast hang around so long.

Roasting/Storage/Extraction

Roasting

I roast once a week using a Hottop roaster that I overfill to 350g. They say the max is 250g, but for a medium roast, you can go higher. I put the beans in when I start the machine instead of waiting for the drum to come to temperature. I’m aware that is not standard, and I’m okay with that. I have yet to do a side-by-side comparison of charge temperature, but I’m sure I will one day.

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When I started collecting data, I was ending the roast at 1 minute past the First Crack (FC). Now, I’m at 1:30 past FC. I used to blend beans before the roast, and now I do it after the roast.

#coffee #data #data-science #espresso #food