I did two roasts today and the expereinces could not have been more different. First, my setup. IR2 vented out the window with a dryer hose, it is cold and snowy and a little windy. No thermocouple, no fan to power air out the vent hose, and my personal 5 stage roasting curve (nothing fancy, just a steady ramp up in temps) My first roast was Aged Sumatra, 150 grams. I'm not sure if it was the hose, the wind, my voltage, or the amount of beans (I've done 150s before), but the fan was clearly struggling to move the bean mass around. The temperature came up slower than usual and seemed to stall at the end of each stage of my roast. I could not hear 1st crack real well, but the beans had clearly expanded, even though the cracks continued to faintly show up. When my IR2 went into it's last, highest temperature stage, the fan was clearly too low. A few beans popping out here and there. The color looked C+, but I was shooting for FC+ and was waiting on the break between cracks, then second crack to start. Suddenly I smelled smoke and saw a few oily beans popping out. I looked out the window and there was quite a cloud of smoke exiting my vent hose. I hit cool down, but felt defeated. This roast had fought with me the whole way and I feel like I lost. When I took it out of the IR2, it looked very uneven, some dark and oily, some more of a C+. I was feeling pretty dejected. I don't have nearly enough time to roast and the thought of ruining one was just depressing. An hour or so later, I went to do my second roast, Greenwell Extra Fancy Kona, 150 grams. I started up the beautiful green beans and hoped I didn't ruin another batch. Man do I love this bean! The temperature (on the IR2 readout) ramped up nicely. The color transitioned smoothly from green to yellow to cinnamon to light brown. I had a very clear, audible 1st crack. Bean circulation was great. When first ended, I gave it an extra 45 seconds to brown up nicely and hit cool down. They look PERFECT! I could not have been happier after this roast. I know Kona is overpriced and overhyped, but I have enjoyed every roasting (and drinking) experience with this bean! I'm glad I ordered 2 more pounds. I'm done with roasting today and I'm glad I ended on a high note. Homeroast mailing list Homeroasthttp://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.com
Seth, FWIW, I found that with my IR1 I could roast 150g... sometimes. Certain beans agitated well, but others didn't. I often found myself shaking the roaster to manually agitate the beans. Was it was something about the various sizes, densities, surface textures; the phases of the moon? I can't say for sure. I ended up doing all my roasts with 130g loads. It seemed to slow things down and I didn't see the hit-or-miss agitation problem. Might be worth a try. Bob
Bob, I've found that bean movement depends on air flow, which depends on the amount of chaff. Low-chaff beans (especially decaf) move a lot more than high-chaff beans (dry process). Also, peaberries are smaller and denser, so they don't move as much. Bean quantity is important, too. Less beans means less chaff, which means more bean movement. I always roast 4 oz, so this hasn't been a problem. Plus I get an even number of roasts from each pound of greens. Mike On Mar 1, 2008, at 3:03 PM, Bob Hazen wrote: <Snip> Homeroast mailing list Homeroasthttp://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.com
You might count the beans. Have you noticed that roasts where the numbe of beans is even are a little more predictable in movement compared to roasts of an odd number of beans? Brett On Sat, Mar 1, 2008 at 4:46 PM, Mike Sieweke wrote: <Snip> -- Cheers, Bretthttp://homeroast.freeservers.comHomeroast mailing list Homeroasthttp://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.com
My IR2 struggles with any more than 125g of Sumatra (especially Lake Tawar). I just figured it was the size of the bean; in my experience Sumatras expand a little more than other coffees in the roast.
Brett, Do you mean before or after the roast? It >may< be best to count before and after, then average the results. Unfortunately, if you include after-roast results you won't know what you should have done until it's too ate. -smirk- (geez... my BSD is clanging loudly) Bob
Whenever I count the beans, it is before the roast - you know, there's all those jumpers, and that messes with my math.... Actually the only counting I have ever heard of was when Les roasted a drum roast with the exact count of one bean.... Brett On Sat, Mar 1, 2008 at 7:57 PM, Bob Hazen wrote: <Snip> -- Cheers, Bretthttp://homeroast.freeservers.comHomeroast mailing list Homeroasthttp://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.com
On Sat, Mar 1, 2008 at 8:11 PM, Brett Mason wrote: <Snip> I think this follow the theory of the "missing sock in the dryer". You always seem to come out with an odd number of beans after roasting, even when you make sure there was an even number going in... -- Dave Kvindlog iHomeroast Cedar Rapids, Iowa Homeroast mailing list Homeroasthttp://lists.sweetmariascoffee.com/listinfo.cgi/homeroast-sweetmariascoffee.com