Good news: I finally got an outstanding Vienna roast out of the Sumatra
Classic Mandheling! It is sweet, the "earthiness" is nice yet not
overpowering, and the body is excellent. And no ashy taste!
Bad news: It was completely undocumented because it was done on my lunch
break as and emergency "I have to roast now or I won't have anything to
drink tomorrow" roast. Fortunately, I know broadly what I did different.
Now I finally understand why others like this bean so much. I think in the
past I have just messed it up by roasting too quickly. The total roast time
in my Modded Poppery II was around 11 1/2 minutes, so it was still pretty
quick...But I was doing the whole roast in around 9 minutes. Also, I think
extending the drying phase a bit helped. The thermometer in the bean mass
read about 360-365F from about 2 minutes to 5 1/2 minutes, and then I
brought the fan speed down to ramp up the heat & induce the first crack
around 6 minutes. Continued ramping the heat (turning the fan down) a little
through the end of first, then backed it off to keep the thermometer around
450F for 4 - 4 1/2 minutes till the thermometer went up on its own, and then
ramped it up a little to jump start second crack. Stopped the roast about 35
seconds into second. (that is vienna right?)
I am sure there is room for improvement, but the cup (French Press) is
excellent with 21 hours rest.
-today is one of the really great days. Normally they are just great.