Hi,
Does anyone else get this small crash after first crack? It happens with a variety of bean, power, and batch sizes for me.
When I look at other people’s graphs, I’ll see a smoother trajectory.
If you do have this, are you satisfied with your roasts?
I’ve tried settings that make the curve look like others, but I get baked flavors when I do. So, I’ve had to keep returning to what the machine seems to naturally do, but that dip after FC also seems to be partially responsible for uneven flavors.
Here is a screenshot of the FC bump and dip nature:
*I added the white arrows to exaggerate the curve.
The temperature RoR lag or dips seem to happen when the most moisture is coming off the beans after yellowing and most notably after FC.
The only way I can avoid the crash is if I add heat back in. Reintroducing heat into a roast is generally considered a bad thing, but it does seem to help with those sweet FC aromas.
Is anyone else getting this same issue? Do you have to introduce heat after FC? What did you do to remedy it?
Here is a roast with P7 and 8 used preventing a slump in RoR.
The red line is the airflow temperature, and about 10% cooler readings that the IBTS. These are not accurate temperatures of the air inside the stump, just the temps near the bean chute it does however help convey what the air is doing. You can see exothermic reaction during the start of FC, but then a rapid decline in ROR held up by increasing power. It doesn’t matter if I hold at P9 or steadily drop power into FC, I get a bump and slump reaction and have to add power back in.
Does anyone have any guesses as to a cause? Is it really just the way I am applying power or fan?
Given that no one has replied all these weeks, it seems like no one else has experienced this behavior?
I have seen another roaster getting similar results, but I forget their roaster name here. Also they appeared to have done it intentionally, so I doubt it is exactly the same.
This is for an 800g batch.
Anyway, I see those coffeemind profiles and have never been able to replicate them. Just curious if anyone else has issues trying to copy those profiles?
Ran some natural anaerobic coffee through the machine, and that one roasted very easily with a very “coffee-mind” like roast curve and Power application.
Typically I’ll roast washed coffees, or naturals that roast a bit more like a washed perhaps.
So is that it? Are you all just roasting naturals and anaerobics? No one doing washed coffees?
Interesting. Was just having the same issue with an Ethiopian bean (washed). Seems to happen no matter what I do. Will give the extra heat a try.
Thanks for the reply!
@paulheinrichslxs5
At least the way it seems to be behaving on my Bullet, is that FC releases heat, but also steam, and since the airflow is either too cool, too or too fast, it may be cooling things down after the initial reaction. (The alternative of slower fan might help in some way, but does not allow proper drying throughout and there is a lot of smoke and chaff build up at lower fan speeds)
I’m not sure if adding heat helps or not yet. Just started doing that. There is a sweet aroma, so I’m hopeful it is doing something good. Will cup or brew by this weekend.
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It looks like you’re maintaining a drum setting of 9 throughout the roast, is dropping your drum setting to 8 an option?
I’ll try the D8 setting. Thanks
Anyone else getting this behavior at FC for washed coffee?
