Sweet Maria's Behmor Roaster Guide - v 1.0
1. Features, Purchase 2. Using the Behmor 3. Roast Quality, Roast Curves 4. Maintenance, Longevity 5. Summary
We spent time doing a variety of roasts, the full gamut of batch sizes and settings. We have been impressed in general, and find that it compares well to our Probat commercial roaster. (My sense is that if I had my old Diedrich roaster, I might find even more similarity in roast taste, since both are highly convective/radiant, whereas a Probat is more conductive in its heat transfer).
Our recommendation with the Behmor, out of the box, is to stick to P3, use 1/2 Lb or 1 Lb batches, and attend to the roaster carefully, especially in the later part of the roast. Note: Beginners might be better off using P1 until they feel comfortable idnetifying what First and Second Crack sound like. Visibility is somewhat limited, so the most important skill you need to use the Behmor is to know the sounds of the roast (1st crack, 2nd crack) and to hit the Cool button at the right point. Sure, the roaster is automated and will do that for you ... but you will rarely hit the target for the exact degree of roast you want by letting the roaster complete its automated cycle. Just like a pro does on a larger roaster, you need to use your senses and past experience, and judge the roast for yourself.
But there's another issue: let's call it "coasting". Like a big roaster, the coffee continues to roast itself after the air cooling cycle starts. You don't stop a roast on a dime, you stop it over a length of time. (Hey, a rhyme!) The coffee stays inside the drum for the cooling cycle - so cooling is not rapid. You need to learn to anticipate this, and stop your roasts BEFORE your desired degree of roast. This is why the rule with the Behmor is, "Don't exceed 10 seconds into 2nd crack." If you do, your roast will end up much darker than you may desire. (The other reason for this is safety - if you roast to a rolling 2nd crack, and add this coasting effect, you may come very close to combustion! FIRE!)
In terms of roast quality, the common wisdom for a roast curve is to warm up the coffee from green to yellow to brown at a rate that allows for even heat transfer within the bean and within the batch. That means no scorching and no "hotspots" in the drum. You also don't want to see excessively slow progress, baking the coffee rather than roasting it. Too much energy in the roast system at a later point in the roast is not good either, as the coffee will quickly pass from 1st crack to 2nd crack, making it difficult for the operator to target the right degree of roast, and affecting the development (and reduction) of certain compounds that result in good cup quality.
The fact is, the P1 Behmor warmup stage results in an even transfer of heat to the coffee, and not too fast or slow. The issue is that the coffee enters 1st crack with a bit too much energy, and the beginning home roast operator might have trouble getting to the Cool button at the right moment. We think that's worth it, because there are other combinations of roast settings that will fail to reach your desired roast level, even with maxing out the time "ceiling" limit on the Behmor. We have cupped the various roast profiles, and feel that P1 rates as well as the others with the majority of coffees. (With the exception of Brazils perhaps ... for those we like P2).
Interested in what Behmor users are saying about this machine? Check out the Using Drum Roasters section of the Sweet Maria's Forum.
P1: Full Power. We recommend this for your initial roasts.
P:3: Seems effective but I prefer P4 for this type of progression
Here are some results from temperature logged roasts, various settings at 1 Lb. (click on chart)
P4: A slower roast curve that seems effective but you might bump up against the maximum roast time limit occasionally
P5: This is the slowest roast and often maxes out the maximum time limit ceiling of the roaster. Use with caution.In general, I would have this criticism of the Behmor roast curves ... they don't offer a true variety of roasts, and they don't make a lot of sense. By that I mean, they seem to have been created rather aribitrarily. They make for some confusion in that regard. But with that said, they offer some avenue for user manipulation of the roast, and we may yet discover some interesting results for various curve/time combinations, probably with the collective effort of the home roasting community.
Behmor Roast Results
We have images of the results from many roast settings, and notations for each will follow. Remember that these images, photographed under strong light, might underrepresent the color of the roast. So if you see a dark, even -surface image, it is probably FC+ or darker, even Vienna. And a patchy surface might be between C+ and FC, whereas in other lighting it would look a lot darker. A few images here, especially the 1/4 Lb batches roasted on the 1/4 Lb setting, were seriously underroasted. That's why you see a set of images of 1/4 Lb roasted on the 1/2 Lb setting.
For example , this is an FC+/Light Vienna, even though it looks lighter. This is from a 1 lb batch at P1/A
And this 1/4 Lb batch on 1/4 pound at P1/A is a light City roast.
- Interested in what Behmor users are saying about this machine? Check out the Sweet Maria's Coffee Home Roasting Forum for more conversation about this home roasting and other home roasting topics.