another_jim wrote:I'm sort of fixed on
0 - 1 min to 250F (basically top speed)
Top speed of course is relatively to ones setup! If I went top speed with the Rosto (~132v to heater, ~144v to fan) and my 1/2# batches for a minute it'd shoot past 300f. For whatever arbitrary reason I've chosen 200f as my 1min mark, 250f two minute mark.
1 - 4 min to 300F (drying phase, an absolute must)
Same target temp @ 4min
4 - 7 min to 380F (top speed again, the longer you're here, the worse it tastes)
Here again top speed with a qualifier you've mentioned in the past, top speed while maintaining even bean color change.
With my over sized slow moving 1/2# Rosto batches faster than 4 minutes to start of 1st from 300f usually results in too uneven going into 1st. But agree too slow will/can result in a dull
7 - 11/12 min to the end, 11 for brewing, 12 for espresso (balance fast vividness and slower sweetness)
But I'm now experimenting with an extra step, slowing down to 10f per minute through the first crack, and speeding to 15f/min afterwards. I'm hoping this will produce a better tradeoff of vivid and sweet. It'll take a few months before I can decide.
I've come to the preliminary conclusion my current ~6min start of 1st to end of roast too long. Not baked, but not enough acidity definition or vividness as you describe I believe.
Did a roast of my espresso blend today changing two stage parameters from posted above: increased 300f to 400f ramp rate for 4min total time (was 5 min, 4min is actually my norm
for most non-espresso roasts already), decreased start of 1st to end of roast from 6 min to 5 min using straight 10f/min ramp 400f to 450f end of roast. Likely won't test resulting shots 'til Sunday young 3&1/2 days rest then will adjust the three test roasts to split and send half of each to Abe next week accordingly. Of course could have should have done two roasts today each with only one changed stage but where's the challenge in figuring out the results from that!
Mapping today's roast profile realized I haven't done any serious profile experimenting since Dec '05, date on my current profiles sheet! Man time flies.