Behemor roasting profile curve

[seijinn]

Hi there,

I am receiving my behemor 1600 this week and I'll start testing when I get it, I've noticed John provide recommendations on roasting per beans but I cant figure how that can be translated into a roast profile on the behemor.

let say as an example for the Belize beans indicate: The profile curve associated with the spider chart is 10.5/2.5/3 @ 255 F. 

how would you setup the behemor to achieve that?

Thanks

Luc

[Chip]

I think one of the things we do as chocolatiers (amateur) is overthink things.  The Behmor is an excellent roaster for cocoa.  Just put it on 1 pound (for 2 pounds of cocoa beans), push P3 (profile 3) add time until it reaches 19 to 21 minutes, listen to it pop, smell the amazing aromas that come off, and then make your chocolate.

[Ben]

Chip's right that the various preset profiles on the Behmor do a pretty good job. That being said, the Behmor 1600 Plus (undoubtedly what you're getting) has the ability to do manual control, so you can theoretically match John's profiles. The problem is that there's no way out of the box to measure the temperature of the beans. I found a couple posts on some coffee forums several years ago that show how to hack in a thermocouple that will let you do so. John mentions it in 'Ask the Alchemist 191', too: chocolatealchemy.com/blog/2017/1/19/ask-the-alchemist-191

A quick google search didn't get me the posts I read back then, but I'm sure they can be found with a bit of digging.

[seijinn]

thanks both! appreciate the response!

it is so true we tend to overcomplicate on our pursuit of perfection

Luc

[mark]

The Behmor's built in thermocouples only give you chamber temperature and exhaust temperature. If you want to follow John's profiles, you'll need to install a thermocouple that gives you the bean surface temperature. John has a video showing you how to do that here: www.youtube.com/watch?v=aT3ZFSfyex0

There's also an ATA specifically about how the Behmor's chamber temperature relates to bean surface temperature: chocolatealchemy.com/blog/2017/4/20/ask-the-alchemist-202

Happy roasting!

[crabloaf]

Hi

I have a few related questions

1. Is the purpose of adding the thermocouple to the Behmor simply to have surface bean temperature and be able to chart the temps a minute at a time? Other reasons?
2. I can’t quite figure out how to copy a roast profile by programming the Behmor. Let’s say I’m going for 10.5 / 2.75 / 4.25 @258f. It just seems like trial and error over and over. As you’ve already said, it’s overthinking in a way. It just seems that I might have to experiment 20 times and still might not hit the profile.

Thanks

[mark]

Regarding your questions:
1: Yes, the probe gives you bean surface temperature which is key if you want to reproduce the roast profiles John and many others use.
2: If you have the probe installed and wish to reproduce a given profile, you will need to "drive" the Behmor in manual mode. You'll need the Plus model for manual mode.
While this may sound daunting at first, you'll actually find you can follow a profile after a small number of attempts. Be sure to record the bean temp reading regularly, I'd suggest every 30 seconds.

How to start? Load in 1 kg of beans and select 400g P5 22:00 and hit start. Note 22:00 won't be the actual roast time, you'll most likely stop before that.
Right after you've hit start, press P5, this will put the Behmor in manual mode (P5 blinking on the display). You can now control the heater (P5=max, P1=min). Also hit the D button, that will double the drum speed, I find that works well.
Let it run full blast on P5 until you get close to the end of the drying phase which is when you want to pull back a bit. Initially, you might want to go to P4 at 88 C and maybe P3 in the mid 90s. I find I don't have to adjust the power level after I hit development / finishing, it just coasts nicely on P3. When you get to your target EOR, hit COOL, open door and wait for the cooling cycle to complete.
While you're waiting for the cooling cycle to complete, you can now look at the roast you've just done and compare it to the profile you were trying to follow. If you adjust the temps at which you went to P4 and P3 you will see that you can quite quickly get to where you want to be (assume the roast profile you are attempting to follow is "normal", ie has no crazy rate changes). Also, remember ten seconds more or less is not going to have a dramatic impact, so don't sweat it if your dev is 2:40 instead of 2:30 for example. Same with EOR, 258 or 257 will be very, very similar.

Hope this helps.

[crabloaf]

Mark.
Wow, what an amazingly helpful answer. I can’t wait to try this. I’m going to immerse myself in all of your advice.
Thank you!

[mark]

No worries that's what this place is all about, right?

[przemsay]

Do you think it's possible to use the same batch of 1kg beans just to practise the curve on Behmor to avoid wasting multiple 1kg batches? Obviously this 1kg will be then useless, but at least we could practise it without stress of wasting 10€ every time

[Ben]

You'll have roasted out most of the moisture during the first roast, so my guess is that they'll act different in subsequent roasts.

[crabloaf]

Przemsay
Maybe you could practice with just a half kg? Then it’s only €5. 😁