My last gift coffee is three roasts of the same coffee. I've worked with the person who roasted these on education stuff, so that was a nice surprise. It's a lovely Peruvian microlot and the gimmick is that the three roasts were taken to the same ending temperature but with proportional stretching.
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There's a recommended brew spec which I completely ignored. Rather than doing a 1:1 drip in 3 minutes I opted for 24g in a 16oz press with 4 minutes.
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It's a bit unfortunate that percent notation is used (20% development time) as DTR is probably the most harmful idea in coffee roasting today, but at least the modulation chart includes enough information that it's possible to suss out the raw duration values that are far more useful for understanding what's really going on with regard to how flavors connect to the roast.
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My first impression is that the chosen ending temperature for all three of these is too low. That green coffee flavor that I complained about with the Mexican coffee a few days ago is also on display here and that's purely a function of just not getting the coffee hot enough. This is especially prevalent on the fastest roast.
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The mid-timed roast brings up the body. The acidity is slightly muted and presents a better balance in the context of the rest of the cup. Given that these were all taken to the same end temperature, the expectation is that this particular raw coffee flavor would be present on all three roasts. Indeed it is, and it would have been nice to taste this, even if they wanted to stick with light roasts, taken 5-10°F hotter.
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With the long roast, acidity continues to be further muted and this coffee is starting to come across as somewhat flat, still with that background raw coffee taste.
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What I'd really like to taste is this coffee taken a little bit darker to get rid of that raw coffee taste detractor, use the short roast's dry time, the long roast's mid time, and the middle roast's dev time to a higher ending temperature. That should improve sweetness and maybe get some chocolate into the cup.
coffee thread
Bonus: their math seems to be wrong. DTR ranges from 17.06-21.74% (none at 20%) if I'm reading the timing charts right. Converted ranges to seconds within the particular range for ease of comparison and a total for those who want to check my math.
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@neal I absolutely love these fascinating analysis threads. Thanks so much for writing and posting them.
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@gnomon Thanks, that's always nice to hear.
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Overall, my preference is for the mid or long roast as these both slightly diminish the flavor of not getting the coffee hot enough. The middle roast has the best balance of these three and is what I'd generally prefer to drink, though the long roast is hinting at the possibility of some interesting flavors that just aren't getting developed.