So I watched Rao's Basics of Roasting the other day. Interesting stuff. Trying to smooth out my ROR per his method. Here are a couple of graphs. I'm not sure how they are going to cup yet but I'm thinking I'm going to need a bit longer of a roast time for most espresso and 398F seems quite light.

I changed the sampling from 1 second on the 408F to 3 seconds on the 398F, just too noisy.

Neither are as smooth as I think they can be but the crash got a whole heck of a lot better.

Need a little advice on getting to First Crack with a little more energy so I can get a bit more development/final temp/color before the ROR bottoms out.

Jonathan - care to share 1 or 2 key principles he's talking about? Or rather, why are you trying to have more energy when entering first? Does he advise getting into FCs with alot of energy and then just letting the BT ROR drop off and end the roast? Would you like a higher average ROR in dev? Curious what you're trying to play with there....

I think it would be best if you cup and pull some shots before deciding that you need to enter FC with more energy to achieve a higher drop temp. I'd want to taste that 398 is "too light" before letting 398 as a recorded drop temperature inform me that the roast is too light.

dale_cooper wrote:Jonathan - care to share 1 or 2 key principles he's talking about? Or rather, why are you trying to have more energy when entering first? Does he advise getting into FCs with alot of energy and then just letting the BT ROR drop off and end the roast? Would you like a higher average ROR in dev? Curious what you're trying to play with there....

A couple things I took away, beside the constant/smooth declining ROR:

40% Gas @ Charge
80% Gas @ 1:00
60% Gas...
50% Gas...
40% Gas...
30% Gas @ 45 seconds before FC starts
15% Gas @ 45 seconds after FC starts
10% Gas
5% Gas
0% Gas if needed
Those were a starting point, not set in stone.

No gas adjustments in that 1 minute 30 second window around FC.

Also, set your air and forget it. If you're gonna play with it, don't mess with it after the first few minutes.

A couple statements that made a lot of sense were. To prevent the crash, you've got to control the release of moisture/such during the crack. The other statement, a flat period in the ROR before FC will almost always lead to a crash. You don't have to have a flat spot to have a crash but you pretty much always have a crash with a flat spot.

So the reason I'm looking for a bit more energy is that I prefer medium roast for espresso and to get to 410 - 420F and still keep a declining ROR, I think I need a bit higher ROR at the start of FC. I'd also think that I'd want to get out into the 10 -13 minute range for these roast as well. Scott did say that you can keep a declining ROR and hit the 20-25% and get to second crack, it just take some skill to achieve it.

mojoit wrote:I think it would be best if you cup and pull some shots before deciding that you need to enter FC with more energy to achieve a higher drop temp. I'd want to taste that 398 is "too light" before letting 398 as a recorded drop temperature inform me that the roast is too light.

I certainly will, just need to let it rest. I did brew my wife a cup of the 398F today, she said it was decent. It's a little fresh yet but at least she didn't spit it out.

Interesting. I hate his 20-25% DTR window. That took me down so many rabbit holes of trying to fit roasts into that guideline. There are TONS of people on here roasting at 10-15%. Not for second crack though obviously.

Its weird that on my quest, I rarely have the FC crash, if ever. My huky, I definitely had FC crash ALOT. I always theorized that the crash was caused by keeping too much moisture in the bean and its just getting dumped out at FC and throwing your probes off. I don't really cut heat too much on my quest (because the little guy doesn't store heat like a big boy roaster) but I want to try doing it. Certain roasts recently I've cut heat a good bit towards the end and not a whole lot happens; I almost want to do that earlier and let the roast cruise out to my drop. I actually think me keeping heat on could contribute to the outer bean developing too much and not leading to even flavors (particularly cause the quest is quite conductive).

Yeah, I think that's the challenge of us home roasters trying to use theories developed for machines that weigh hundreds of pounds more, roasting exponentially larger batches.

He did say that when roasting smaller batches, the DTR can shrink. Again, that statement is developed for big machines.

What is DTR?

Development Time Ratio, the percentage of time the roast spent in the phase that starts at first crack.
i.e. 10 minute roast, first crack starts at 8 minutes, 20% DTR.

Got it, Thanks! For some reason it's the 75%-80% to 1C that always stuck with me. It seems a lot harder for darker (or super-light) roasts. I'm surprised he said you could still meet it going all the way to 2nd crack.

The only way I can see getting to second crack with a constant declining ROR would be to charge lower, hit the heat hard and coast it down slower. Thought proposition!

I just don't think the initial ROR can't get up into the high 30s or low 40s.