Drastic First Crack Temperature Difference

Just thought I’d post to ask the community what the highest first crack temperatures are that they’ve experienced. I roasted a natural 18 Rabbit coffee from Honduras today and didn’t hit first crack until around 407°F (according to the IBTS). The Black Honey processed version of this same coffee hits first crack at around 392°F. I’m very surprised at the extreme difference considering these are the same coffees. Have you seen any similar behaviors in coffees roasted on the Bullet? What’s the highest first crack temperature you’ve seen?

To clarify, I’m defining first crack as the time when I get at least 2-3 pops in quick succession, ignoring initial outliers. I also noticed that first crack tends to go on for a very long time with this coffee. I had to drop after 2:18 due to reaching 425°F and not wanting to roast this as a dark roast. The beans were still popping in the tray! I may have to go into dark roast territory just to see when first crack ends.

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I’ve not experienced that yet.

I’d say normal. You also have a Brazilian, which is not known for density, cracking at 404. I don’t know if you clean your IBTS regularly, but it could be responsible for these, I’d say, small differences. Also, using newer firmware that helps keep IBTS clean is a good thing.If not, the coffe from the same farm is not actually the same coffee. It could be incorrect storage. Maybe you know how it was stored when it got to you, but it might have lost some moisture along the way. Maybe the grainpro, ecotact or what have you, bag got a little punctured or ripped. It happens. The processing might have affected it but, even if all this turns out to be not true, and there really is a difference, I would not worry about it. I’ve had these differences between beans with different density, but never had 2 differently processed coffees from the same farm.

I’m not too worried about it, but thought it was interesting that it seems to have a very high FC temperature and a FC that goes on for much longer than usual. Oddly enough, even though the black honey processed version is about 6% denser than the natural processed version it cracks at a much lower temperature. I think this is a good example of why every coffee needs to have it’s roast “dialed in” even if the coffee comes from the same farm and elevation from around the same time. It’s amazing how much of an effect the processing method (or possibly storage) seems to have!

All that said, the coffee turned out great. It’s fruity and complex as many naturals are. Surprisingly no roasty flavors despite reaching 425 :grinning:

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