ROEST L100 Plus

If you want to learn more about the ROEST, visit our FAQ page in the Coffee Library, and also see the PDF documents in the Downloads tab above.

Have some questions or want know more about buying one? Send us a message at [email protected].

I thought I would write something a bit more personal about how we came to use — and now distribute — the ROEST Sample Roaster, so here it is:

It took us two years of daily use of our ROEST Sample Roaster to finally have the bright idea of, "Hey, maybe we should talk to them about a partnership!"

Why didn't we think of that sooner? Well, we are a business focused on home coffee roasting (and with Coffee Shrub, supplying micro-roasters). Selling $8000 machines isn't really in our wheelhouse. At the same time, we have constant demand in our own coffee labs to evaluate samples. It would be great to use home roasting machines to do that, but it's just not feasible. For the volume of samples we evaluate (sometimes its 60+ per week) and with our need for very high consistency and repeatability, a coffee lab needs something more.

For years that has been a vintage three barrel Probat sample roaster. Roasting three coffee batches at a time certainly meets our needs, and with skill and focus (a lot of focus) the results are uniform and consistent. But increasingly the real life struggles with old style sample roasting started to rear their ugly little heads. 

While you can turn out a lot of sample batches per hour, it takes 100% of your attention. You really can't do anything else but roast. While it's not that difficult in theory, it takes quite a long time to really master a particular sample roaster. (Just think of how long it takes to teach someone else ... not just to do one batch, but to turn out 30 uniformly roasted samples. It takes time...). And increasingly we found that with various distractions, conversations, calls, little business issues, we were blowing more roasts and needing to do them over.

At first the ROEST became our go-to option when just a few samples came in, or for a late arrival when we didn't want to take 30 minutes to heat up the Probat (or 1 hour to cool it down). The ROEST is ready to in under 5 minutes, and cools in less than 15 to shut off. 

But over time we found the reasons to go to the ROEST over the Probat, even when we had 15-20 samples, more compelling. First of all, the old drum roaster has no profile we can realistically apply during the process, especially when running all 3 barrels. Even if we could, that would be rudimentary changes to air flow and small heat changes. With the ROEST we were designing specific curves using the 5 sensors, and in particular using the automated First Crack Detection to automatically determine development time and end the roast.

Once we had the curve we wanted for a particular coffee (we primarily are using and Inlet Air Temperature-based curve we created for 100 grams of washed coffee), all we needed to do was put the green coffee in the roaster, and remove the roasted coffee from the tray. We set it for 1 minute 40 seconds development time starting after 2 audible cracks (the machine almost never misses the sound too!) and the ROEST does the rest. It automatically ends the roast, releases the batch into the cooling tray, and is ready for us to put in the next batch immediately. Cooling while roasting means a lot of throughput, and makes up somewhat for only roasting 1 sample at a time versus the Probat.

Although the ROEST is using a temperature based profile, not time-based, if we had similar sets of samples, say 30 washed Guatemala coffees, the roasts are finishing in an incredibly tight range. If we get 7:38 on an initial batch, we would see times within 10 seconds of that, batch after batch after batch. That meant that the sensors and OS processing the data were dead on accurate, with no discernible time or temperature creep occurring no matter how long we ran the machine, or other variables like ambient temperature etc. 

This has also made a huge difference in the quality of my work day. If I get distracted by something or someone, not a batch is lost. If I get pulled away for 10 minutes, the machine is there waiting and ready for the next batch. If I need to send an urgent email or take calls, I can see the batch automatically end, and the ROEST is ready when I can get back to it. I mean, I like all the focus the Probat roaster takes, but it's taxing, and on some days I find a whole bunch of roast errors on the cupping table I have to re-roast. That doesn't happen with the ROEST. It's really the ultimate user-friendly machine.

We started out simply using the basic program for 100 grams that ROEST has loaded on the machine. There's no need to get into it more than that initially. That is a Bean Sensor based curve. I liked it, but some coffee with different physical characteristics, say a Sumatra vs a Colombia, would roast differently. So I simply duplicated that curve and changed it to an Inlet Air Sensor curve. I just clicked a couple buttons, and loaded that new curve to the machine. Later I made a few changes to some of the set points in the temperature profile. It took a couple minutes ... I never had to come up with anything from scratch, I simply took the curve from a roast I liked, cloned it and Voila! Later I made one for decaf with some lower temperature targets and extended finish, just by dragging some of the set points around.

And I took the original curve and made one with milder heat ramp for doing 50 gram and 80 gram batches. All of this was intuitive and send to the machine via the the online interface. Plus I could share them with Dan in Seattle, who by this point received our second ROEST L100 Plus in black/aluminum material. So now we had calibration in our roasting between Oakland and Seattle, could develop roast profiles easily for different coffees and know we were tasting the same roasted material. 

Lately I have been trying to "model" the roasts from other machines on the ROEST, which is the only sample roaster I know of where it is actually realistic to think you can take 100 grams of coffee and reasonably create a Loring or a Probat profile. With 5 sensors and 3 fans to control, it seems you can go pretty deep into playing with variables like drum air pressure in a way that wouldn't be possible in other roasters.

There's a lot more I could say but I think that sums up the basic ways the ROEST has made my life easier, saved me from a lot of "DOH" moments and small frustrations, and allowed me to get other things done while still roasting samples! I'm usually on the opposite side when it comes to technology, automation, and machines taking on more stuff that used to take trained and skilled workers. (Think super-auto espresso machines that never go on strike). But I just can't deny that ROEST has really improved my work and our operation, and that we're excited to offer them here to anyone else who thinks they might benefit from adding this machine to their coffee operation.