Below is my standardized, not bean-specific, generic recipe that I try to follow for a 1lb (about 454g) batch, especially when the bean is new to me. An example chart is below.
Preheat (about 15 minutes for day’s first batch) to 464F, P7, F2, D9. I start lowering the power one step at 330F (IBTS), another step at 360F, and then decrease power and/or increase fan as needed while trying to achieve slowly decreasing RoR (trying to control spikes or drops) and a low RoR (around 5) at the target end temp.
For light/City roast I target 395-400F, City+ around 405-410F, Medium/Full City around 415-425, and then higher for Full City+ (rarely go higher than 430F end temp).
Usually I reach FC at around 385-395F, in between 7:30 and 8:00 minutes. Finish roasts in around 10 minute mark depending on the roast level.
Does anyone have this type of standard (not bean specific) recipe to share, or any comment/improvements on my process above would be appreciated!
No, most of the time I get pretty good result. I am still learning and just wanted to see if anyone has any suggestions, to make sure I am on the right path at least. Random commentary is welcome!
I tend not to use a recipe per se when it comes to a bean I am unfamiliar with. I prefer to create targets and aim for them… Typically, I start with “how long do I want my roast to be, for this particular variety of bean?” Then I try to decide on my end temperature as a guideline, but I usually use color and smell to end a roast more than temp. The temps just give me an idea of where the roast should end. Once I have that set, I try to figure out my drying time, Maillard time, and development time I want. For those transition points, I have generic numbers/temps where that usually occurs for me. Once I have that, I know what times I am trying to hit particular temperatures. The last thing is charge temp. For that, I usually just use the guidelines in the manual, with higher temps for denser beans and lower temps for less dense. Once I get that first roast done, I’ll make adjustments based on my cupping experiences.
Thank you for sharing your thought process. How do you go about lengthen and shorten those phases (drying, Maillard, and development)? Lengthen by decreasing power or increasing fan, and shorten by increasing power or decreasing fan? Do you plan out those adjustments before roasting, at least roughly?
Yeah, power and fan are pretty much what you have at your disposal to make adjustments during the roast. Before you start the roast, there is charge temp and batch size too, which would influence those numbers as well. Familiarity with your machine and the beans helps you make good guesses as to what to do when.
As far as planning, when I make adjustments, I have a rough idea - EG, I usually step down my power when IBTS reaches 150C or something… but exactly when is more based on an observation of what is happening during the roast and keep an eye on Rate of Rise, etc… If I am supposed to hit FC at 8 minutes, which I expect around 198C, I’m 6 minutes into the roast , Temp is reading 178C and my RoR is 15 or 16C/min and declining slowly, I’m probably going to hit FC sooner than I want… RoastTime has a nice little “Predictor” curve you can turn on too, to help with those estimates.
And on another note, I try not to make a ton of adjustments in short succession either, as those don’t help make predictable, repeatable processes.
