Preface: This is based on some of the open conclusions I have been slowly understanding. There are things I cannot physically have you taste nor know of how to perfectly apply it to your roaster. This is just a topic that will have to be mulled over, trial-ed (on your roaster) and generally a topic for thought an openness discussion. Saying words like "conjecture" would be a mute point so I hope we can have some clarity that we are speaking from our own references. So without further adieu...

I feel like there are actually three main areas for flavor development during the roast:

1) the charge, speed and length of green (creates the creamy coffee aroma in roasted bean, also where I add more or less heat based on Millard, too fast can cause tipping)
2) the Millard, speed and length (too short = pea/vague acid with no flavor, too long and hot = meat, long and not too hot = chocolate)
3) "Developement" (for clarity please refer this the phase beginning with a capital "D") too slow and coffee dies, too fast and coffee burns)

The umbrella topic: I would like to discuss how this all effects the "landing" of the roast. More specifically, the entry into Development. My ques for understanding a good roast is the development of flavors coming from my exhaust vent aka trier (I understand this is not a healthy option so I take quick sniffs). A great profile during the end of Millard or for some beans the end of Development I smell a fruit aroma, fruits are my goal. I used to chew on freshly roasted (directly after cooldown) and 10minutes rested beans and I could taste if there were fruit notes or others and generally how good or bad the roast was. When my roasts were landing (during the chaff release I call expanse, at the end of Millard beginning of 1C, I can smell either green notes (pea, cucumber etc) or fruit and generally try adding more heat before this on the next trial. If no smells I would readjust the total profile usually by adding more heat along the z-axis, since most of my profiling come from a low to high heat approach. (I am working from a roaster, Ikawa At Home, that only does preset profiles based on input heat) I use 1C sounds (loud or soft, lots of cracks or a couple and sometimes none. As an indicator for applying heat.

Recently I have taken to roasting (or reroasting some failed batches that didn't make it up to sniff (after resting in ziplock containers). I have noticed that if I stay along the course for a pea flavor with lots of heat and developing with a sharp roasted note this tastes exactly like most Starbucks roasts. This landing into and then developing that initial pea flavor turned into Starbucks, but usually I would have adjusted to get fruit on the nose (by enough heat from green and Millard) before Development, which to me and my profiling Development is just the area to make the bean more brittle and a good Dev would keep the fruit or (in the case of Sumatrans) create fruit (so I would be technically landing my roast for Sumatrans at the end of Development).

How do you, where do you "land" your roasts? Do you have indicators (what are they)? Do you agree/disagree with what I said?

I'm not sure what you are asking. Please try to narrow your question, if you can.

Hey Drgary, over the weekend I have been thinking about this concept and how to simplify it but I do not have the mastery of this concept to do so. "How am I landing this roast?" Is one of the questions that I ask myself while creating a profile. I understand especially with Hoos's book the concept of adjusting length of time during different stages effects flavor, but doesn't go into "speed + ROR". Tied with this: if I lengthen or shorten a phase do I also adjust the temps, or the speed? Since I have to create a profile before I start roasting and then make adjustments for the next batch, it requires a lot of pre-planning.

Maybe a better way to say my OP:

Do you conceptualize a roast plan before your roast?
Based on the concept of milestones; do you have certain ROR's during the different phases you like and hit for certain coffees for particular flavors?
Do you notice these effecting the end of your roast?

Are you saying how do you hit milestones and maintain momentum so you can land it without crash or flick?

Also there's a way the stages transition, so charge sets up end of dry, which sets up Maillard, which sets up development. I'm starting to pay more attention to ROR at the transitions from end of one phase to the next, if that helps.

Charge temperature is a starting point. On my roaster time of the soak before powering back on, ROR from end of dry, ROR going into 1C, and if needed ROR going into 1C sufficient to reach 2C. All of this is a tall order, and I'm still learning, hoping to make fewer adjustments as I anticipate better.

drgary wrote:Are you saying how do you hit milestones and maintain momentum so you can land it without crash or flick?

Yes, I am asking more or less asking how you do it. Avoiding crashing a flicking is a significant role for maintaining and keeping the flavor but how are you creating flavor?

So if you crash and flick you basically crashed, but how do you take off, fly and prepare to come in? To be aeronotical about it. Not looking just at how green/dry effects flavor but the hopscotch through all the milestones and how one phase leads and effects the next, and so on.

You've said you can set your charge temperature but you can't tweak the roast profile with your Ikawa Home model, but you can choose from pre-set profiles. That makes it difficult without getting specific to what Ikawa pre-set profiles to choose from your menu.

If you even had a heat gun/bread machine roaster to experiment with, we could compare approaches because you would be able to manually make adjustments. Does a HGBM exceed what you can get with the Ikawa or vice versa? No idea!

Maybe this might help your understanding of the Ikawa At Home http://www.vimeo.com/126287904
I buy my greens from SM and create my own profiles. I cannot make adjustments during the roast and with the Home model my charge (I consider) is the profile at 1-2minute mark. In the pro Ikawa the charge is like a normal drum roaster.

The Ikawa is simply a machine that sets a consistent temperature. I'm sure I can roast just as well on any machine that is able to reliably control temperature.

crunchybean wrote:Maybe this might help your understanding of the Ikawa At Home http://www.vimeo.com/126287904
I buy my greens from SM and create my own profiles. I cannot make adjustments during the roast and with the Home model my charge (I consider) is the profile at 1-2minute mark. In the pro Ikawa the charge is like a normal drum roaster.

The Ikawa is simply a machine that sets a consistent temperature. I'm sure I can roast just as well on any machine that is able to reliably control temperature.

Thank you. I'll take a look at the video while others chime in.

I'm guessing there's two points the OP wants to discuss.

1. I find that the smell just when entering the first crack is a good preview of the coffee. In the first crack itself, the acid vapors mask the coffee aromas, and later the caramels do.

2. Cutting the heat in the Maillard to get the right landing at the end depends on the thermal mass of your roaster and bean mass. On a 20 Kilo Probat, you're stepping down for most of the roast. On my little Quest with a 125 gram load, I turn back the heat 5C ahead of the first crack. This is purely local knowledge.

I think one source of confusion might be that much of the advice on roasting is geared for people who control heat input directly, rather than as mediated by a parametric control function. So when I start a roast I don't choose phase length, I choose heat level, charge temp, and then the timing of future changes in gas or air levels. If I have roasted a coffee before I'll know what to expect with phase lengths and can adjust accordingly.

In general I like to shoot for an approximately parabolic BT curve that tapers close to zero ROR in the last few seconds of a roast (which would correspond with a linearly declining ROR). So "landing" is a decent metaphor for that idea of slowing down to a near-stop just as a coffee has finished developing. But in practice it is good not to oversteer to achieve this, and I mainly just try and time adjustments to get phases of reasonable length and avoid a crash or flick, and then drop when the coffee smells right.

The best phase length and finish temperature will vary based on origin, bean type and other considerations. If you want to shortcut the trial and error process of figuring out which phase lengths work best on your roaster, consider buying greens where you can find publicly posted profiles by people using similar gear. In your case, you might want to check out Royal's Crown Jewel offering of small 22-lb lots (which you can then split with other home roasters if 22 lbs is more than you want). Royal does some of their test roasting on an Ikawa and they post the profiles with tasting notes, which might help get you started.