I have been roasting on a 2KG Buckeye roaster for some time now, and I finally feel like I'm getting the hang of it. I just thought I'd share some of my findings so far so that 1) I can get some feedback on whether I'm on the right track or not and 2) possibly help others who might be going through the same problems I've had.
So here it goes:
1) Start with the best quality beans. Oh man, I started with cheaper coffees, and for the life of me, I couldn't figure out whether the cupping results were a roasting issue or a green bean issue. Once I started sourcing strictly from Nordic Approach (which in China is the most reliable source for traceability and reliability without getting samples), I was able to deduce the issues. So as to eliminate variables, definitely get the most reliably good coffees you can source. If you're in the US, then you have tons of sources for this. Please do not skimp on quality. You will always pay for it in the long run
2) Roast curves all so relative. With my roaster which reads a ton of the faceplate temp (just like Tim Wendelboe's), I realized that I really can't follow any of the curves posted here on this forum or anywhere else. So then what's the solution? 1) Rob Hoos has really helped me a great deal. His emphasis on focusing on different chemical process points has allowed me to think of roasting in a transferable way. 2) Trial and error. Nothing beats the diligence of continually tracking improvement from roast to roast.
3. DTR% (development time ratio) as a concept is BS when comparing one person's method to another. Obviously, within a fixed system (aka Rao's, or Mark Michaelson's for that matter), you can think of development time as a percentage in a relevant way. But from roaster to roaster, coffee to coffee, style to style, the DTR is totally wrong. I messed up so many roasts because I thought the DTR had to fit within a certain window. Some of my roasts go to 25%, others go to 12%. They all taste good based on the coffee & taste profile I'm going for. Coffee roasting should be thought as much more fluid than many people want it to be for the sake of simplification.
4. It's all about your palette. Some like it light, floral, fruity; others dark, bitter, and roasty. Some prefer lots of sugar cane sweetness, others more caramel/chocolate. You are the master of your roasts, so don't let others dictate what tastes good for you. But if you know that there others who have attain your desired flavor profiles, do follow them.
5. Follow your palette to your source. I love lighter, juicier, sweet and fruity tasting coffee. That leads me to favor green coffee sellers like Nordic Approach. Others are more open and variable. I love Sweet Maria's/Coffee Shrub for this reason. They always give you the full gamut of what's possible with a given coffee so that you can buy what you like. Others don't necessarily do this. Find your desired profile and source accordingly.
Next post I'd like to post mainly on technical findings. Hope this helps others!