NoStream wrote:FC-start temp: 391 F (approx. 10 F higher than usual).... I was attempting something like a slow start, fast finish profile, something which I haven't really attempted before. Anyway, I wound up being a little too generous with heat at the start (around 5 amps vs. maybe 3 or so), so drying was a little fast.

More than a little. In addition to power, your Charge temp was way too high for what you were trying to do.

For small Charges like you're using, you want a lower Charge temp in general, and especially for pulped naturals, honeys, and the like. 325F is a good starting point for these type of processes. I slow/fast/slow nearly all my roasts -- Charging at 300F -- but that might not be a profile you want to play with until you've had a little more experience with the Quest.

You can use a low Charge temp and a high power setting to push the time to Turning Point and EOD -- but those are things you generally don't want to do. I suggest a very low power setting at Charge, then increasing a little after the TP. Use power and air to help you hit your EOD time target. Don't settle for letting the roaster's settings carry you along -- participate in the roast by riding them.

Last, I'm not a Quest user, so take it with a grain of salt, BT is a vastly more important metric than MET.

Rich

Thanks for the suggestions, Rich. Those were exactly what I was hoping to get from participating here.

It definitely seems like a good idea to charge a little cooler and then apply more power. I had enough thermal inertia that I would've basically needed to coast through EOD with no power.

I guess I'm trying to figure out just how low, since I want enough energy to get through the turning point. Also, my Quest has a bit less thermal mass than your roaster, and I'm getting MET, not ET (should really replace my thermometer ET with a thermocouple), so it will mean I have to charge a little hotter. So maybe around 375 F for this coffee? After cupping this, I'll probably try an espresso profile based on your recommendations.

Just based on your Dry/Ramp/Development ratios, it seems like a slower start and a faster ramp are in order, at least for the kind of profile you want to execute. Charging cooler, and then applying more heat to keep up the pace after turnaround, seems like the way to go.

Absolutely, agreed. I will probably do 375 charge, increase power a little through dry to get around 5-5:30 to EOD, floor it to an MET of around 460-480 where I think scorching will set in, getting a ramp of around three minutes, and back off into 1c, dropping at ~410 after ~2 minutes of development.

I think the biggest problem with this first roast was that I charged too hot and applied too much early heat, and then I couldn't catch up later.

[creative nickname] wrote:Thought provoking as usual, Tom. 7:15/3:45/1:30 is a pretty radical espresso profile; I generally want at least 2 minutes of development before I'd consider a roast a good candidate for espresso, as most coffees have too much acidity to be tamed without more development than that. But you are probably right that this particular coffee might pull great shots with fairly light roasts. Now I'm curious to experiment with something like this myself.

On small roasters like the Quest, roast development ( from 1C to drop) happen proportionally faster than any commercial roaster I've ever used. A minute post 1C even at tip-toe'ing heat/airflow is equivalent to 2+ on pretty much any coffee I've sampled off larger roasters where I monitored the profile firsthand. And I'm not referring to just an artifact of stretched out 1C phenomena due to larger charge of beans, I'm simply talking about bean color, texture and expansion and how it cups.

NoStream wrote:Very interesting profiles. Would you mind either posting slightly larger pictures or listing the numbers? Also, could you clarify what the black line is? I'd assume MET, but those numbers are higher than my MET probe reads, and higher than I believe they are in other roasts of yours that I've seen. Or maybe it's just due to fan settings.

Thats just my MET, which should be taken with little consideration. It's highly positional (as are all my probes except for my new exhaust air temp that I'm loving, which isn't shown on the graph). You'd have to extrapolate what MET you need to see on your system in order to achieve the BT development waveform you want, at specific time/temp landmarks.

Even insulated, the little Quest has such small thermal mass and slow electrical elements that it has to play catch up if you crank the heat and fan at the same time at EOD. So, on my profiles, nearly always, you'll notice a little dolphin fin hump mid profile usually starting around 280-290BT I crank the heat to max for 20-25 seconds to re-establish/build up my MET before even touching the fan. It's a useful way to ensure that when you're hitting the gas pedal on a roast that you want an aggressive ramp, that you're not lagging behind (because the fan just sucked out all of the little available heat you had).

Its one of the niggling little downsides to the Quest where any gas powered roaster doesn't have to fight to re-establish the heat they want. But knowing it, and learning how to predict how the roast/roaster reacts, I can sidestep any problems. I've actually found doing this beneficial in the cup, since doing so seems to allow the greens to linger ever so slightly longer in the early onset of the EOD phase where they're light tan. On most Quest roasts, beans can go from green to straw to tan extremely quickly, but then cup out tasting somewhat thin in the middle. Not lacking development per se, just weaker. Anecdotally, I've found what I'm doing above to give me better tasting coffee, more resonant flavor intensity. I'm currently enjoying a La Mula Geisha I roasted a few days ago thats like drinking perfume it's so intense.

Tried my first roast this evening:



Started lowish and ramped aggressively through 390* and then backed off a little on the bottom conductive heat to cruise through FC. Dropped at 3:00. Roast looks very nice. Clean bean. Tick-Tock...

UPDATE: I tried a cup this morning on 12 hours rest. Not bad. It needs another day, but it was very approachable. I nice round, laid back acidity. Nothing offense. Not the chocolate burst I expected.

Espresso pulled with this bean is quite pleasant and extremely sweet. I picked up some very interesting Colombian greens from Red Fox Importing that will likely also shine in the mix.

(Proposed)

• Roaster: JGR (Jolly Green Roaster), a USRC 1lb Sample Roaster;
  Charge Wt: 400g;
  Charge T: 300F;
  Profile: 6:00, 4:00, 3:15;
  Drop T: 432F (eight snaps into 2d); and
  Finish: FC

Is Chris Schooley still involved with this? I bought 10lbs of beans with the idea of using his experience as a starting point, but guess I'll have to start without him.

In my limited experience with them, since Natural Brazilians don't have a lot of acidy flavors, and can do with some roast character, they're good candidates for going darker than the usual C and C+ many of us use for wild Africans and character filled SHG Centrals. So far, though, I'm seeing low Drop temps in this thread.

While I'm not advocating for Vienna... Anyone taken this into 2Cs yet? I'd like to know how FC works for espresso. Presumably it's going to be right around 40F greater than 1stCs, which -- given my familiarity how some of the roasters used for results already posted here compare to mine -- will mean a 1stCs @ ~390F; and -- extrapolating a typical ~40F delta from 1stCs to 2dCs -- a 2dCs @ ~ 430F in mine.

Putting together the things Chris has already written about Brazilians (on the Shrub website) with our recent interest in Rao, I think a 6:00, 4:00, 3:15 profile to first eight snaps of 2d should work pretty well for Brazilian, Declining RoR and 20% - 25% Development Ratio. So that's what I'll shoot for (either today or tomorrow). Without a preliminary "roast event" roast, I won't be able to anticipate milestones very well and probably won't approach my ideal profile very closely on my first attempt -- but will try anyway.

Rich

boar_d_laze wrote: Is Chris Schooley still involved with this? I bought 10lbs of beans with the idea of using his experience as a starting point, but guess I'll have to start without him.

I've checked in with him several times. Last word was when he received his greens and was in the process of his first roasts (last week). I originally held off with my commentary on the coffee until some time had passed and I just chose to post what I had so far.