Recently I have been working on making a lighter roast profile for a natural processed Brazilian I have. I started experimenting with dropping gas pressure extremely low (.5 kPa) once I hit rolling FC, then letting the exothermic reaction drive it to drop temp. I'm sure this will be mentioned so I'll confirm now, the roast never did stall. Was wondering what you guys think. At the end I'll share my cupping notes.

Here's the graph. Notice how much it plateaus during FC.

Bean info and weight start/end.

Lastly, this is everything I did during the roast.

CUPPING NOTES:
-First off, this VERY good. I have roasted and cupped this bean at all roast levels and this was by far the best. Great acidity and flavor, heavy mouth feel topped off with a lasting, non bitter aftertaste. Oh and the dry aroma was to die for. Not too intense, maybe a 2/3, but amazing aroma.

Sorry if I missed this but is your HUKY configured with the solid or the perforated drum?

Solid drum, faster motor variant.

Nice looking roast. If you love the flavor, you got a winner. But you should set Artisan to show BT rate of rise. It revels a lot of info not easily seen in your graph. Also set the font size a bit bigger. It's kind of hard to read.

I also roast on a Huky. I have the perforated drum, slow motor. I like to drop in a little hotter to shorten the drying phase so that I can get a longer ramp phase. To do this, I drop 350g in at 410f with full gas and 50% fan. Then at about 3-4 minutes into the roast, I drop the gas way down to 30%, and fan down to 15%. Then a few minutes later, gas goes way down again to 10-15%. At first crack my rate or rise (ROR) is even lower than your 15f per minute. I end up with a ROR of 7-10 in development which allows me to end my roast way down at 410-415f, but because of the slow, longer development, it tastes about as bright as your 425f end temp. Just a thought. Fun to try. It seems to change the style of the brightness to a softer more delicate brightness. I recently got an amazing dry processed Brazil roast using these parameters. It's basically a fast start, slow finish style roast. Like 3:45, 4:10, 2:10. Ending 410f in 10:00. In spite of your slow down at first crack, your roast is more of a slow start, fast finish style.

That's pretty crazy you can drop at such a low temp without under development. Would you mind sharing some of your logs if you have any on hand?

Nice roast, sounds tasty. You can end at a lower drop temp. by managing the ET, getting it closer to BT during the last leg of the roast. I step the gas down on my solid drum Huky, 4kpa, 3kpa, 2kpa, 1kpa, .75kpa, .50kpa, roasting 1lb. It doesn't appear the Huky ET probe has much bean contact, which I find to be very useful. The analogue ET gauge is junk and should be tossed and replaced, or just get it swapped out for free on a new machine.

hipporun wrote:That's pretty crazy you can drop at such a low temp without under development. Would you mind sharing some of your logs if you have any on hand?

Keep in mind that the perforated drum/slow motor HUKY is an entirely different beast than the solid drum/fast motor HUKY. Aaron is using the perforated/slow configuration (as am I), and with that configuration everything happens differently. I tried and tried and tried to emulate the profile of a friend with the solid drum and we spent a long long time speculating as to what was wrong with my HUKY until it finally dawned on us (as a result really of a graphic that Hank shared of the different airflows) that they were such entirely different roasters.

Even if you do exactly what he does you will not get the same results he does....It's all those holes in the drum....)))

Here is the roast I was describing.

Aaron, is this the first roast in a session?
Or is it a follow-up roast?

If it's your first roast, how do you prepare/warm up for the charge?
I ask, because my MET never exceeds ET or BT until after I have charged the roaster. Up until Charge, BT is the highest temp, followed by ET and tailed by MET. After charging, they change places.
Your profile shows MET way up there from the get go and so I'm wondering how bring the roaster to charge temp.

This roast is from a cold start. Ambient temps in the 70's. I warm up with shutter and damper open, 15% fan and 60% gas. Nothing special. That's odd about your MET, or is it my MET that's messed up? Did I notice some probes had different placements depending on how old the Huky is?? All my roasts show a similar MET curve.