
The Node Chroma:
Nick Cho: An iOS replacement for an Agtron?

Home-alone roasting session. #instacoffee (via Instagram, by way of an IFTTT recipe.)

Roasting scribbles. @sweetmarias Costa Rica Chirripo Los Crestones – Finca Alaska. (more at its Instagram page). (Posted by way of an IFTTT recipe.)
Roasting Notes form v1.0»
It’s a PDF. I’ll be starting to use this on my next roast. Feel free to suggest any additions and, of course, to download it for your own use.
Roasting Journal
A predominantly disorganized (data-collection practices improving, but not perfect) data-dump and question-pondering for Yemen Mokha Matari, batch #2 & Yemen Mokha Harasi, batch #1, with some tasting notes thrown in for good measure
Temp & Time – Matari #2
| Start Temp | First Crack Temp | End Temp | First Crack Time | End Time |
|---|---|---|---|---|
| 75º | 395º | 425º | 4:20 | 6:40 |
Cavaet roaster1.
Weight – Matari #2
| Start Weight | End Weight |
|---|---|
| 100g | 83g |
Color variance
Roasted, there is a stark difference between the level of color variance, from bean to bean, of the Matari and the Harasi. The Harasi? Dramatic. The Matari? Only slightly more variance in color from bean to bean compared with anything else I’ve put through the popper.
Not sure why. Initially, I thought maybe there was a larger disparity in size and shape with the Harasi but glancing at the beans in each bag, it’s difficult to say. Both bags display an incredibly wide variety, with beans of all shapes, sizes and structures.
Total roast time
Where the Harasi’s trademark is dramatic color variance, the Matari’s is length of roasting time. 6:41 for batch #2. About a full minute longer than any other coffee I’ve put through the popper. I roasted a bit lighter for this batch. Batch #1 was darker and took the longest of any bean so far — 7:39.
Why? Bean density? Mmmm…again, not too sure. Imperfect as it is, I took a volume measurement of both — both 1/2 cup and 1 cup — and weighed them. One or two grams difference. Gonna go ahead and say that would be in the accepted margin of error.
I’m at a loss from a quantitative standpoint. Qualitatively, they’re both delicious.
Matari #2 — Taste Notes
Dark chocolate, little to no acidity, subdued, light fruit — dried raspberry — peeking through. Very dry finish.
Harasi #1 — Taste Notes
Intense dry dark chocolate, subdued acidity, big fruit — dried currants, dried raspberry — with a dry finish.
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These temperature measurements are are taken from a used West Bend Poppery II air popcorn popper, with a hole drilled into the top for an off-the-shelf stem-thermometer to go through. So, you know, keep that in mind. ↩
Roasting Journal
Yemen Mokha Harasi, batch 1.0
This was the most uneven roast I’ve ever gotten out of the popper. I am unsure why. Maybe it’s the qualities of the coffee itself. Maybe it was ambient temperature — it was 97° outside at the time — and the roast was too fast. But that wouldn’t be a cause for unevenness.
Maybe it’s because it’s an air popcorn popper. Every batch of every coffee I’ve put through it has had some level of color variance, but I’ve roasted five different coffees already and this coffee shows the most extreme variance in roast levels from bean to bean, on the same roast batch, of any of the others. I mean I’ve got beans the color of a SoCal surfers sun-bleached locks mixed in with roasty-toast little nuggets the color of a s’mores marshmallow tragedy (some people like ‘em that way but not me). So…hmmm.
The thing is, from what I know about natural process African coffees — and if I ‘m remembering correctly, especially coffees from Yemen — the processing is especially primitive. The processes in place are the product of historical necessity. The water supply to process coffee with the wet-processing methods of Latin America just is not there. It never has been. So while I’ve always heard that dry-process coffees from Yemen can be “interesting”, I’ve not heard them talked about for their uniformity or excellent grading.
So maybe what I’m getting is a double-whammy of uneven density and size due to less-than-sophisticated processing methods endemic to the producers of Yemen.
And I’m roasting in a popcorn popper
We’ll see how it tastes.
Roasting Sweet Maria’s Kenya Nyeri Ngunguru Peaberry
AKA: things I learned, and things I learned I had already learned1, my first time roasting coffee
General thoughts
In no particular order…
The longer the roast, the more moisture is lost, the lighter and less dense the bean2.
The 5:00 roast lost 9g
5:14 lost 12g
The lightest roast of the bunch sounded like rocks going through my grinder.
Data, data, data. I need more data.
I’ll get over the nervous jitters and the process will become second-nature and then I’ll be able to devote greater attention to taking more meticulous notes.
For the past four roasts I’ve been focusing on logging when 1st crack is happening (somewhat challenging at the moment: “Was that it? … wait, no, that was it …) and what the total roast time has been.
Moving forward, I can see me focusing on temps at which these things are happening as well as focusing on how far past 1st crack I’m reaching the temperature at which I’m satisfied with the color and smell (that’s going to be an interesting qualitative data point as well) I observe in the popper.
West Bend “Poppery II”
As I’ve said before, rumors of the West Bend “Poppery II”’s scarcity have been greatly exaggerated.
The “Poppery II” produces far, far less smoke than the literature at Sweet Maria’s and other sites has led me to believe.
There were warnings to place the popper under a stove ventilation hood. There were warnings to take the popper outside to roast the coffee. I saw pictures of modifications using metal ducting to direct the smoke outside. “It must be four-alarm fire type of smoke for all of this effort”, I thought.
I’ve produced more smoke grilling chicken indoors. A lot more.
If you must, sure, place the popper under your stove’s ventilation hood. But really, there isn’t much smoke and most of it is released during the first minute of the roast. Not an issue.
Of course, I could eat my words. Maybe Central Americans or non-peaberry coffees produce more smoke. Maybe this batch of coffee was an anomaly. I must remember: this was my first roast.
I’m duly impressed with the evenness of roast I’m getting … out of a popcorn popper. It’s not Probat quality. But it’s more than workable.
The best and most efficacious bit of advice I read was to place a bowl with a wet towel in it under the popper’s exit chute. Worked like a charm at catching the chaff and preventing it from blowing in all directions.
I read the process was going to be noisy. Again, not much of an issue, especially for someone who uses a burr grinder every morning and lives to tell about it. I own a Cuisinart ice cream maker that makes more noise and takes a longer time to achieve desired results.
The coffee: Sweet Maria’s Kenya Nyeri Ngunguru Peaberry
This is a beautiful coffee. It reminds me of a Kenya I had at Intelligentsia — I think it was the Tegu (PDF). Like that, the Nyeri is brothy and sweet.
Below city this coffee is disgusting. Really. I tried to drink it. I didn’t get far before tossing it into the sink. Grassy. Like I steeped hay in a cup. The sharpness of the fruit is tenaciously, still present but without any. sort. of sweetness. at all. to balance it out. Not good.
At around city the Nyeri just goes bonkers with the fruit. It’s sharp and wild. In a good way. The brothy-ness (miso) undergirds it, just barely hanging onto the fruit (cherry and sweet cranberry), preventing it from getting too carried away.
At around city+ balance prevails. It’s the more sophisticated older sister of the Nyeri at city. The sweetness takes more of the stage with the wild fruit. It’s a more sophisticated, balanced cup without losing the fruit.
I thought, if I may, that at city, it had the light and wild fruit of a good Ritual roast. At City+, it was more representative of what I remember from the Intelligentsia Kenya mentioned above.
I like both. I really can’t decide which is best. I suppose I don’t have to.
The nicest compliment I received was that
It tastes like the coffee you usually get
…from my roommate. Peet’s fan. So, you-know, objective.
Three more pounds of green coffee are on their way from Sweet Maria’s. This is fun.

Informal tasting tomorrow with m’lady. Four roasts down. Already time for a new bag of green.
The West Bend Poppery II and a bag of Kenya Nyeri Ngunguru Peaberry from Sweet Maria’s are on their way to my door.
The image of the Poppery II above is from this eBay seller but you can search eBay for (many, many, many) more, from the cheapest, most run down $5 model to many new-out-of-the-box examples going for around $45. Mine cost $12.99 + $15.00 shipping.
Things are about to get smoky.




