Roasting Profiles for Espresso? - Page 2

[another_jim]

This is where I'm confused. If 7-10min to 415f from start of 1st @395f, a 20f temp rise, and experimenting with 10f/min ramp doesn't fit the 3 minute 7-10 minutes!? Also if I understand correctly, you're using a total time of 5 min from start of 1st to end of roast for espresso roasts? (Which happens to be what I just shortened mine down to from 6 min with good results.)

The final ramp(s) starts at 380F; look at the chart. I want to slow the beans fdown ahead of the first, since the colors get uneven there. The speed up after the first is based on the same theory: "go as fast as keeping the colors even allows."

[another_jim]

Jim - is this a preblend? I have both of those in my stash, I'd love to see if I get similar results.

Actually; it'll probably taste beeter to take the Cenaproc to the first pops, while pulling the Idido a little ahead of that. Use a lower dose and finer grind than your usual for these lighter roasted blends.

[miKe mcKoffee]

The final ramp(s) starts at 380F; look at the chart.

Duh, so I need glasses!

[Martin]

I want to slow the beans fdown ahead of the first, since the colors get uneven there. The speed up after the first is based on the same theory: "go as fast as keeping the colors even allows."

I've been using these benchmarks for some time. IMO, it's the most convincing argument for on-the-fly (instant-response) control. Conversely, it argues against any set-and-forget programmed roaster unless the electronics are very sophisticated, one has lots of experience with a particular bean/crop, and environmental conditions are stabile from roast-to-roast (which, basically, applies to a tiny percent of home roasters). Absent these conditions, most folks would do well to sit and watch---- with their hand on the throttle. This "ramp-rule" may also explain a portion of the bad rap small-batch air roasting gives to air roasting generally-----thinking here of very fast roasts.

I'd add that the "speed up" when 1st is about to get going helps shorten or compress the duration (for most beans) of 1st c., and it therefore allows a longer gap between 1st and 2nd, if that's what one is after.
Martin

[miKe mcKoffee]

I'd add that the "speed up" when 1st is about to get going helps shorten or compress the duration (for most beans) of 1st c., and it therefore allows a longer gap between 1st and 2nd, if that's what one is after.
Martin

That's one profile approach, like my profile #3 current profile roast comparisons. Currently both Jim and I were experimenting with the opposite though for espresso roasts: slow through 1st then speed up after 1st to end of roast (not necessarily to 2nd.)

[Martin]

That's one profile approach, like my profile #3 current profile roast comparisons. Currently both Jim and I were experimenting with the opposite though for espresso roasts: slow through 1st then speed up after 1st to end of roast (not necessarily to 2nd.)

I'll be interested in the findings from these experiments. Admit to my post drifting a bit. As you might assume, HG/DB is not an finely tuned experimental tool; however, it can follow roasting principles that have been established over time. To me, the key is to translate those principles into roasts. That #3 (I guess) is, IMO, rock solid for many beans.

Martin (a man of few principles)

[miKe mcKoffee]

I'll be interested in the findings from these experiments. Admit to my post drifting a bit. As you might assume, HG/DB is not an finely tuned experimental tool; however, it can follow roasting principles that have been established over time. To me, the key is to translate those principles into roasts. That #3 (I guess) is, IMO, rock solid for many beans.
Martin (a man of few principles)

While I'd been using mostly fast-slow profiles start of 1st to end of roast for quite some time (variations of #3 being tested) been recently having excellent results with slow-fast (like #2 but 3:30 total time) for beans like WP Yirg'. With WP Yirg' my theory was going for a complete bean City+ with a kind of intra-bean melange effect darker FC outer bean only. I really like the results in the cup, but this isn't for straight shots but rather primarily Americanos and cappuccinos. If WP Yirg' meant for primarily straight shots I'd take the total start of 1st to end of roast time longer than 3:30.

[another_jim]

My results are in. The roasts wth the speedup after the first crack were brighter, despite going to the same roast level in the same time. If you check barista techniques, you'll see this no longer bothers me; and the resulting shots taste substantially better. The nougat from the Cenaproc and the florals and apricots from the Idido are all there, but the oddball to annoying green tea bitterness from the Idido is not (green tea has its place, but, IMO, not in espresso shots).

[HAL9000]

My results are in. The roasts wth the speedup after the first crack were brighter, despite going to the same roast level in the same time. If you check barista techniques, you'll see this no longer bothers me; and the resulting shots taste substantially better. The nougat from the Cenaproc and the florals and apricots from the Idido are all there, but the oddball to annoying green tea bitterness from the Idido is not (green tea has its place, but, IMO, not in espresso shots).

Wow! I wouldn't have expected that. Not that I am an expert or anything....

Am I right to conclude that based on this you don't see much value in "stretching" between first and second, but rather only during first, and then want to race to the end?

Also, when you say these roasts were "brighter," I am assuming that, though they were brighter, they still sweetened up, which I guess would be the whole point for you (and incidentally, for me too) given that I gather you like the sweetness, and quite a breakthrough. Just looking to clarify. If that's the case, I'll try that right away.


Thanks Jim, very interesting!
Paul

[Martin]

Wow! I wouldn't have expected that. Not that I am an expert or anything....
Am I right to conclude that based on this you don't see much value in "stretching" between first and second, but rather only during first, and then want to race to the end?
Also, when you say these roasts were "brighter," I am assuming that, though they were brighter, they still sweetened up, which I guess would be the whole point for you (and incidentally, for me too) given that I gather you like the sweetness, and quite a breakthrough. Just looking to clarify. If that's the case, I'll try that right away. Thanks Jim, very interesting!Paul

I'm also no expert, but I have opinions anyway. With my degree of cupping skills, I find it extremely problematic to distinguish between degree-of-roast "brightness" and ramp/duration brightness-----especially with limited roasts of particular SOs or (forgetaboudit) blends. I'm also struggling with some water softness/hardness-brightness issues since direct plumbing and locking into one grain or under.

I've learned to pay close attention to Jim's analyses. And I'm looking forward to this current line of thinking after, say, another year. Until then (or, who knows? something more definitive) I'll stick with my default 10 oz, 6-7 minutes to first; 7.5-8 to 9.5 quiet; and maybe some slow second. Coaxing primo brightness will have to remain a function of degree-of-roast for those beans that offer distinctive brightness as well as going through the trouble of post-roast blending.

Martin

[another_jim]

My post here on the new profile are a work in progress. I've switched grinder and machine since I came up with the old roast profile, and the quality of greens available to home roasters has also jumped, with SM, Terroir, Paradise and a few others selling COE, auction, and relationship greens. All this change requires a reexamination of my roasting practice, since it seems likely that my old style might not fit the new setup.

The whole beauty of home roasting is that one can gradually adapt every part of ones coffee making process to all the other parts. Most people don't make a big production out of this; and they may be right. After all, it happens all by itself. But I have academic pretensions; so I need to come up with justified reasons for doing what I do; I feel naked without them. The only justification is that my musings inspire other people to try new things, and this advances the state of the art.

[Martin]

But I have academic pretensions; so I need to come up with justified reasons for doing what I do;

. . .and that's why I pay attention. "Justified reasons" not being so far from "theory." And theory is quite some distance from much of what's available, which are descriptions of momentary, ungrounded (pun-aware) instances. It's only with the greatest respect that I say that I'm waiting for a fuller discussion of the observations reported and the generalizeable reasons why.

Given the relationship among "every part of ones coffee making process to all the other parts" and the idiosyncratic differences in each of our kitchens/labs, it's the theory that connects individual efforts. I've a few academic pretensions of my own, and I know where (not here) I'm creating knowledge and where I'm simply trying to use it.
Martin

[Rainman]

Jim- what grinder are you using now? I noticed in the "bench" forum it looks like Teme is wondering how the M3 is holding up. I just ordered a Kony, so I'm a little curious, too.

[another_jim]

Jim- what grinder are you using now? I noticed in the "bench" forum it looks like Teme is wondering how the M3 is holding up. I just ordered a Kony, so I'm a little curious, too.

The M3 bearings are holding up so far. The straight through design remains very convenient for experiments -- put 12.0 grams in, and get 11.8 to 11.9 out, and no coffee from the last cup. The way the bur carrier is locked for grinding, just a screw, is not so hot -- it's not very repeatable at fine grinds. For that, I think the Mazzer springloaded design is best, since it puts even pressure all around the burr-carrier's thread.

It looks like the Kony, the Macap, the Max, and maybe the Compak, will become more easily availble this year. It'll be interesting to see how they fare.

[HAL9000]

Still curious Jim, bright and sweet? Or bright and not so sweet?

Paul

[cafeIKE]

For that, I think the Mazzer springloaded design is best, since it puts even pressure all around the burr-carrier's thread.

Has anyone with academic pretentions actually measured, say with a nice lazer interferometer, the supposed improvement in the spring loaded Mazzer. Springs can be nasty things, storing energy and releasing it at the most inopportune times.

I measured the backlash in my M4 upper burr carrier with a dial gauge and it was about 2 tenths. 1 wrap of .004 teflon and it is now 0 with a 30lb displacement force.

Not sure if any improvement results as I cleaned the grinder at the same time. I did back out the grind 1 complete revolution on the worm adjuster from the pre-cleaning mark.

Thus far the missus has not mentioned any decline in the taste of her cappa's

[TimEggers]

1 - 4 min to 300F (drying phase, an absolute must)

Hello Jim,

I don't want to intrude on this very interesting and educational discussion, however I would kindly ask you to elaborate (if you would be so kind) on the importance and affect of the drying stage on the later parts of the roast and more importantly the resulting cup.

I have begun my attempts at understanding the drying stage and how it correlates to the other aspects later in the roast such as the conversion of starches to sugars and then the caramelizing of those sugars.

Could you offer me any information or refer me to some readings that may enlighten me in this regard?

Thank you very much!

[another_jim]

I have begun my attempts at understanding the drying stage and how it correlates to the other aspects later in the roast such as the conversion of starches to sugars and then the caramelizing of those sugars.

Maybe "drying" is the wrong term, and iot shoub be more like "even heating to 300F." The symptoms of too short a dry phase are chlorogenioc acid tastes (green-bitter/bright) in the roast, especially it's a light one, and inadequate caramelization.

Two things happen between 300 and roughly 380F. First the Maillard reactions start, these turn sugars and amino acids into flavor compounds. Secondly, the remaining water in thebean turns to steam, starting at the center, where the pressure builds to around 15 bar and working outward in a coherent front (this from Illy). The energy required to create the high pressure steam depressed the temperature at the center of the bean. If the temperature of the coffee is not equalized before this it gets extreme by the time the fiorst crack is reached.

The first crack is the point where this steam fron breaks out of the bean. It is also the point where sugars begin to caramelize, and fruit acids, including the chlorogenic ones break down. Even in the best roasts, the beans become uneven at this point, and one wants to slow the roast, so the beans even out in color by the time the first crack starts slowing down. If this is done, one can stop the roast at any lightness with good results. If the temperature differencs are extreme, as in too fast a start, the beans never even out unless one bakes all the flavor out.

However, one can overdry the beans. Water is needed for the Maillard reactions and for caramelization, so a very dry bean will get flat. In the experiment where we pulled iudentical profiles for air and drum roasters, the air roasted beans tasted flatter (an effct only apparent experts, so quite subtle). This is why four to five minutes, maybe even three, is sufficinet for this stage in an airroaster, while one needs around 7 minutes in a drum.

The safes way is to initially roast the beans by sight, and keep them ibelow 300F until they all are a uniform yellow, but no longer than that. I thinkl 4 to 5 minute is about right for most airroasters, although 3 might be the ticket for very dry beans (say old crop ones), and 6 for excesively moist ones.

[TimEggers]

Jim,

I must thank you very much for your timely and very informative response. I sincerely appreciate the time you took to enlighten me. I will keep your comments in mind as I continue in my home roasting experimentations. I also especially appreciate your distinctions between air roasting and drum roasting as I do mostly drum roasting and I understand you do alot of air roasting.

Thank you once more!

[cpl593h]

Jim, I have to hand it to you... Your 50/50 Cenaproc/IMV blend roasted using your latest profile method is sheer delight as both espresso and drip. I need to tweak it a little more, but it's a winning forumla.