I bought 5 pounds of Bali Blue Moon Organic from Happy Mug and have done a first roast to a finish of 426.2F IBTS. After four days of rest the cup is very tasty with some brightness, thick mouthfeel, a mix of dark chocolate and earth, low bitterness, smooth, a touch of sweetness. Just wondering if anyone else has roasted this bean and, if so, did you get more chocolate at say 430-435F, or is 426 far enough? I was shooting for 15 seconds into 2nd crack, but even with a stethoscope in the tryer hole I’m not positive I heard 2nd crack; so, in the interest of not going too dark I ended it there.
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I haven’t roasted this exact Bali Blue Moon lot yet, but I’ve roasted the very similar Sulawesi Toraja Pango Pango on the Bullet R2 multiple times.
Second crack on these wet-hulled beans is often surprisingly quiet, but you will definitely hear it with the stethoscope (at least I hear it with my stethoscope, usually closer to 427+ °F).
If you want even more chocolate and body while staying in clean light-oil Vienna, I recommend dropping a bit higher next time at 430–435 °F IBTS and targeting a DTR of 25–28 %. Out of curiosity, what DTR did you get on your roast at 426.2 °F? At that temperature you’re still on the lighter side of Vienna. These beans definitely tolerate and reward higher temps.
I tried a curve that had been working for finishing at 410F and my DTR at 426.2F was about 29%. I did a second roast of the Bali three days ago and ended at 431.4F, using some different parameters and ended up with a DTR of almost 36%. I’m not used to going darker than about 415F, so my curves don’t look very good. Still, the coffee has come out tasting very good both roasts. I have linked the two roasts below.
Thanks for sharing the curve and the update on your second roast — really appreciate it!
Glad to hear both roasts are tasting very good already.
On this latest one ending at 431.4 °F with ~36% DTR, you’re getting solid results, but targeting a lower DTR (25–28%) will improve the cup even more with better balance and sweetness.
Looking at the curve, the development phase after first crack is running quite long. To drop the DTR, the roast needs to slow down a bit post-FC — on the Bullet the fan is your brake, so increasing F in the right places will do the job.
For starters, I’d recommend going to F4 at 10:15 / 394 °F and see how that works. After that roast you may need to increase fan even further to slow it down more if the DTR is still too high.
Curious to hear what your DTR ends up at on the next one!
I appreciate the suggestions. I’ve been wondering how to handle development time with darker roasts. I could make some simple adjustments and get good dry and Maillard times, but then getting up to 430F-435F in a timely manner would almost certainly require upping the power after first crack, and that would result in a huge uptick of the IBTS. I will try using the fan more in my next roast. And I will be sure to keep you up to date on how it goes.
That has been my experience too. A lot of the beans I roast actually need a power boost almost immediately after FC if I want to shorten the DTR and still get up into the 430–435°F range in a timely way.
So I would not be afraid to try it. You will usually see the curve swing upward, but in my experience that is harmless as long as you also increase the fan to keep it under control.
I’ve had very good success using that combination.
After looking hard at the roast curve, I elected to take a chance on AI and so I asked Copilot using this query: “timestamped RoasTime profile for a dark roast ending at 435 degrees Fahrenheit on a Aillio Bullet R2 Pro that keeps the dtr less than 26% using 8 ounces of Bali Blue Moon Organic wet hulled beans”. Well, Copilot came up with a profile; but it didn’t produce the kind of curve I had hoped for. Still, ending at 435F, even with a terrible looking curve, gave me a tasty cup of coffee. I will say that the description Copilot gave of the way the coffee should taste with that profile was pretty well spot-on. I have linked to it below. One thing I did differently than Copilot suggested was to preheat to 419F instead of 570F. Copilot said preheat to 570 then wait until the IBTS reads 420 to charge the beans. My Bullet doesn’t work that way, so I figured starting at 419 would have to suffice.
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Thanks for the update and for sharing the latest curve!
Glad the coffee still came out tasting very good at 435.6 °F even with the curve not looking ideal. These wet-hulled Balis are pretty forgiving.
Yes, the FC came way too soon at 7:30 @ only 380 °F — that’s significantly earlier than the sweet spot for this bean. You’re spot-on: the preheat of 419 °F was too high, which accelerated the pre-FC phases and pushed first crack early. That’s exactly why the development phase ended up so long (4:38) and the DTR climbed to 38 %.
Since your previous roasts at 347 °F preheat gave you a much later (and better-timed) FC, I’d suggest going straight back to that 347 °F preheat next time. Delaying FC this way also lengthens the Maillard phase, which is important for flavor development and really helps bring out the rich chocolate and earthy notes this bean loves.
Once FC lands closer to the expected 9:30–10:30 window, give it a solid P8 boost right at first crack to counter the big endothermic reaction (the sharp RoR drop when the beans absorb heat and release steam/CO₂). That should bring the DTR right into the target 25–28 % range while keeping the clean light-oil Vienna finish.
Having done lighter roasts before now, I’ve been wondering how to approach dry, and Maillard and then have enough energy to get to 435 in short order. I’m inclined to agree that going back down to 347 is a good place to start. If I can hit FC at 9:30, that would allow me to use up to 3 minutes in the development phase without going past 25%. So, the plan (loosely) would be Yellow at 5:30, FC @ 9:30, and EOR @ 12:30 with an end temp of 435F. If I can get close to those times I’ll be happy. I’m guessing F2 until 5:30, F3 until 9:30, and then F4 would be reasonable for the fan. I’ve got my work cut out for me, but with 3-1/2 pounds of beans left, I should be able to nail it sooner rather than later. Incidentally, I have read that a roast that doesn’t seem to change much with days of rest may indicate a fault related to flattening ROR, which based on my last curve is probably what I’m seeing.