You can roast a coffee shorter or longer to the same medium roast level. Length of time does not determine the roast level alone. Temperature over time determines the roast level.

brettpavia wrote:Right, I'm agreeing with you.

So besides using time and/or changing the roast level, how does one manipulate the complexity level in medium roasted coffees?

Grasping a better understanding of what drgary is saying and accurately applying, and in so doing having the knowledge and experience to control the roast so you can apply the advice given is the point you need to be at. If I told you how to do it for one coffee not knowing now that another coffee is going to be different, let alone that you didn't mention how you are roasting the coffee(hardware). And lastly the answer to your question is so advance I think money should be involved to find out.

I also recommend buying Scott Rao's roasting book and memorizing it.

drgary, you, or anybody else has not actually addressed the questions i am asking.

i know how to take the same green coffee and make it a fruit-subtle, fruit-forward, or fruit-bomb and do the same with showcasing earthy notes.

However, i have never seen anybody in published works or on-line talk about manipulating the complexity level of medium roasted coffee. Nor have a seen anybody talking about how to map that our for any even coffee. Do some have a wider range of complexity than others? How does one know if the coffee they are roasting is at its max complexity or if they failed the coffee if max complexity is the goal.

these are easy questions to answer for fruit note and earthy note coffees, the general roast profile concepts are basic. For manipulating complexity while keeping the same body-notes, this is a completely different type of thing. While changing the flavor profile more radically is so easy its from amateurs, keeping the same basic profile but changing the complexity is not.

If your actually doing this regularly... please share about your experience. which recent coffee have you done this with. which body-notes stayed the same, while at the same time what other supporting notes disappeared or become more vivid? Doing all of this without it becoming a medium-light or medium-dark, but staying as a medium roast.

Not asking for your roast profiles, just examples of how you manipulating the complexity while not changing the basic roast level.

Would actually like to taste three examples on the cupping table... not sure you can do it.

brettpavia wrote: ....So besides using time and/or changing the roast level, how does one manipulate the complexity level in medium roasted coffees?

You buy it in the green in my opinion. The roast profile will obviously yield different attributes in the coffee, but you can't polish a turd either.

A specific coffee that immediately comes to mind is the Juan Pena microlots from Ecuador. As long as you don't blindly make horrible mistakes in roasting it, it's very hard to get anything other than amazing complexity and depth of flavor. Many great coffees still only pluck one string or two at a time. Juan Pena grows symphonies. It's like having an amplifier that goes to 11.

From my limited roasting experience, it seems like complexity and depth can also be manipulated via changes in the delivery of heat.

Increasing conductive heat in relation to convection seems to increase complexity. Which means playing around with the air flow, another way would be adjusting the drum speed, decreasing drum speed would also increase the contact time thereby increasing conductive heat.

is there any work done on calculating AUC? Taking into account the bean mass that was roasted might help comparing roasts (like in AUC per 100g, or whatever other amount)...just a thought, it'll never allow taking into account all variables but it perhaps can help translating sample roasting to larger batches in an easier way and might allow playing with other variables that don't show up in AUC like drum speed and allow to 'isolate' those parameters. Will do some searching on the net.

Edit. Of course, sure enough...Artisan already includes the AUC will start playing around with that function.

brettpavia wrote:drgary, you, or anybody else has not actually addressed the questions i am asking.

these are easy questions to answer for fruit note and earthy note coffees, the general roast profile concepts are basic. For manipulating complexity while keeping the same body-notes, this is a completely different type of thing. While changing the flavor profile more radically is so easy its from amateurs, keeping the same basic profile but changing the complexity is not.

roast profiles, just examples of how you manipulating the complexity while not changing the basic roast level.

I tried asking a similar question about chocolate in the cup a little while ago. People were nice and replied but did not answer my question completely. Or to the best of my understanding. As an homage I will try to best explain that what your asking requires more than a grasp of understanding. I can liken it to any master craftsman but the truth is there still a lot of art that is making up for the lack of science, in this trade. It's not that your question is too complex is that the answer is specific-dependent. On what coffee green you are using, what roaster etc etc. for example if you are on a balance beam and you stick out your leg, you have now altered your weight distribution and need to compensate in order not to fall. Each of us here may have a different reactions on how to do that (keep the balance) one may simply need to stick out a pinky, I might have to do more or less. It is all essentially about transferring heat through the roast, how much at what time making/causing things to become available or whisk away. Is all dependent. If you already have the know how and understanding of how to alter your roasting than this is just something to keep in mind as you roast and the intent you wish for each roasted outcome. If not than read both books listed, devise experiments to test hypothesis and collect data, analyze your findings and apply what you've learned. Lastly there are inherent quality differences and resting/storage all play a factor to find the target that always feels like it's moving around. I apologize for not answering you question better.

Given the subjectivity of interpreting experiences, I would love to have a tasting session with HBers where we have people record their interpretations and we see them side by side in a matrix. I've spent years reading descriptions from people with whom I don't share a common experience. Ie. How do I translate complexity?

Rather than a top down positivist argument, we could have a bottom up qualitative exploration. Are there any themes? What do the people with similar reports have in common?

I know my wife tastes different things in my home roast coffee than I do. But she's from a different country and culture. And I think my sense of smell might be impaired. And we also argue over what colour things are.

Whenever I have doubts about my own work, I go sample work from other people to situate myself. A bunch of people roasting the same coffee and showing what can be done with it where I can compare what they say to what I taste... that would be amazing.

What i find quite fascinating is being in a conversation where I realize people are using the same word for different things, or different words for the same things. Then we clean it up.

this might be a good read, what a great coincidence TomC posted this just earlierCommon Roast Defects: Morten Münchow

happycat wrote: A bunch of people roasting the same coffee and showing what can be done with it where I can compare what they say to what I taste... that would be amazing.

It would be fun to take the old Roast and Learn format one step farther by having participants mail 1# of their best roast to the next person in the group, they take a bit, try it and remail it a day later and so on. So if there were 6 people participating, there would be 6 mailings each round and the coffees would circulate throughout the entire group and everyone could cup or takes notes to their hearts content.

The post office would love it.