Is it even possible to underdevelop the bean interior relative to the exterior on a Huky? - Page 2

July 19th, 2022, 2:30 pm

Marcelnl wrote:I too start off with 4-4.5 KPa, get to FC at a similar temp my drop temp is a lot lower (404-407 ish) and my roast also minutes shorter.
Never seen insides much darker than the avg outside color.

Oh wow you drop in a <7-10°F -ish after first crack? For the longest time I was afraid of dropping before first crack was almost completely over (around 425°F). +17°F is the lightest I've done

#12: Post by **Marcelnl** » July 19th, 2022, 2:41 pm

I do,

this a weird one, with a TP temp much higher than usual, I suspect the outside temp has some influence.

FC is at 198 or so (=388F)
drop at 208 (=406F)

#13: Post by **olutheros** » July 19th, 2022, 3:10 pm

Trjelenc wrote: Oh wow you drop in a <7-10°F -ish after first crack? For the longest time I was afraid of dropping before first crack was almost completely over (around 425°F). +17°F is the lightest I've done

You can always slow down your momentum prior to first crack and get the same amount of development time but with a lower end temperature. +10f past first crack is a pretty reasonable endpoint for a light roast provided you spend enough time there (like, I do not think it will taste as good if you hit +10f in 30seconds and drop then, but +10 in 90 seconds might be a perfectly nice light roast)

#14: Post by **rmongiovi** » July 19th, 2022, 4:21 pm

I think the only way to get the interior hotter than the exterior of the bean is to roast with microwaves.

#15: Post by **mkane** » July 19th, 2022, 4:26 pm

#16: Post by **baldheadracing** » July 19th, 2022, 4:30 pm

I'm not familiar with a Huky, but this sounds like it might be internal scorching - perhaps try the solutions from this thread: Internal scorching is kicking my behind. Ideas?

As an aside, "internal scorching" is the name people give to the phenomenon of darker inside than outside. Actual temperatures and physical reasons - the outside of the bean is physically different from the inside - are a separate discussion.

July 19th, 2022, 4:41 pm

rmongiovi wrote:I think the only way to get the interior hotter than the exterior of the bean is to roast with microwaves.

It's not about the interior getting hotter than the exterior. It would be heat quickly getting to the interior and developing the interior compounds farther than expected

#18: Post by **mkane** » July 19th, 2022, 5:05 pm

Soft beans

#19: Post by **rmongiovi** » July 19th, 2022, 6:07 pm

Trjelenc wrote:It's not about the interior getting hotter than the exterior. It would be heat quickly getting to the interior and developing the interior compounds farther than expected

Maybe we're arguing semantics here, but in a normal roaster heat energy is delivered to the outer surface of the bean via convection and conduction. From there it has to travel by conduction in towards the center of the bean. Since the beans are much more an insulator than a superconductor the exterior just has to develop more than the interior. The goal of the steadily declining RoR is to maximize the development of the interior while at the same time minimizing the development of the exterior so that you can get sufficient development of the interior before you exceed your desired development of the exterior.

You can certainly develop the interior more than you desire, but I'd expect the exterior to be even more developed. I'm not certain you can really judge development just by eyeballing the color. The eye's response to color is notoriously context dependent. You'd require a standard D65 illuminant and a controlled surrounding environment to really make meaningful comparisons.

July 19th, 2022, 7:50 pm

Yes it's true that you have to drive the heat through the outside of the bean to get into the interior, but a coffee bean is not homogenous from surface to interior, like a steak would be, so if there's more sugars, acids, etc in the interior than exterior, the level of temperature that will brown the exterior can brown (and degrade, react, etc.) the interior even further. Which is why this issue bothers me: I'm seeing an obvious darker color in the interior, which tells me it's possible I'm degrading flavors I'm looking for