I started roasting coffee recently. Click here for the larger size; very cool shot. Unfortunately, looks better than it tasted. I chose a Sumatra decaf green bean from Yeah, me too on Indianola (Columbus, OH) for starters. For roasting equipment I used an unmodified Hamilton Beach Poppery II (scored for $2.99 from Ebay) and roasted 1/2 cup of green beans for 10 minutes.
I conducted this outside at about 50 deg-F for a timed 10 minutes. Despite the satisfying color of the roasted beans, I think I under roasted them. After roasting them, I cooled them in a cast iron pan (to dissipate the residual heat; halting the roasting by removing residual heat is supposed to be effective) and waited a couple hours before grinding them for a cup of brew in my drip machine.
The final coffee had nice color, reasonable taste, but was a tad winey-tasting. I suspect they were a tad underdone. I also spoke to some friends about my results and they agreed the ambient outdoor temperature* was too low to get a good rich roast outside in only 10 minutes.
I'll be trying this again soon. It's fun, Frankie likes to watch and the final results are never wasted. I think I just need a more reliable endpoint to shoot for. The first crack was faint and barely detected and I don't even know if I made it to the second crack.
Results will be disclosed as experiments continue.
*I did this outside because of warnings from friends about big plumes of smoke when the beans start to achieve a dark roast. I never noticed this. Again, possibly indicative of too cold an environment to get the full roast.
I repeated the roasting indoors (ambient temp ca. 64-deg-F for a full 12 minutes. I was hearing the second crack when I stopped the roasting (first crack around 5-6 minutes). Dumped the batch (1/2 C) into cast iron and it was all shiny and dark. Here's the final product. Tasted as good as it looked.