Matt Perger on Roast Development - Page 7

#61: Post by **N3Roaster** » March 18th, 2015, 3:20 pm

9Sbeans wrote:http://youtu.be/hDc72LpyBr0
In this video clip, Neal demonstrates his profile development process. Starting around 2-min, we can see his default profile, with the distinct re-acceleration after the first crack end, all the way into the second crack.

As a point of clarification, that isn't any kind of standardized default. It's merely the first thing that I tried at the lab roaster. By the time I'm doing that I already have a decent idea of what the coffee is and how I want to handle it. Based on cupping samples from that first roast I altered the profile and ended up with the attached profile. I've put the ROR in (red line, right axis, the blue and cyan lines are bean and air temperatures respectively and read off the left axis) and while you can still see a bit of accelleration coming out of first crack, it's less pronounced.

#62: Post by **9Sbeans** » March 19th, 2015, 6:08 pm

Thank you Neal for the clarification. I pointed it out as a contrast example, purely based on the math, not implying if a roast should pass through the second crack.

Work on the math, assuming a BT Thermo Couple has the first crack readouts at 390F, and with the second crack readouts of 440F. To get a Full City + or Vienna roasting level within a 4-min development time, the average RoR has to be at least 50F/4min, or 12.5F/min. If we want to reach FC+ by following Mr. Perger's suggestion (very slow RoR at the finish; a car constantly slowing down until it reaches a stop sign), we would have to blast through the first crack (probably 20F/min), and hovering around second crack temperature (440F) for 1-min to make the finish RoR small. I would say this is an unlikely scenario.

In other words, Mr. Perger's suggestion is applicable on City + to FC. However, if one prefers a dark roast, it should be easier to drop the bean once it hits the target temperature, regardless the RoR. What do you think?

#63: Post by **endlesscycles** » March 19th, 2015, 7:09 pm

The techniques for roasting coffee well don't apply to roasting coffee poorly.

March 19th, 2015, 8:04 pm

#65: Post by **TomC** » March 19th, 2015, 8:59 pm

endlesscycles wrote:The techniques for roasting coffee well don't apply to roasting coffee poorly.

Who's specifically roasting coffee poorly and why?

There's room under the umbrella for every taste. And every taste can be executed well, or poorly. But roast degree in and of itself does not objectively mean a poor roast.

March 19th, 2015, 11:31 pm

TomC wrote:Who's specifically roasting coffee poorly and why?

I'm certain each of these examples bring coffees to mind.

Matt Perger wrote: ""That coffee is light and well developed." - Hells yeah that sounds great! Bright, sweet, rich and delightful.
"That coffee is dark and underdeveloped." - Boo. This is the worst of both worlds. Ashy, bitter, no sweetness and savoury green flavours.
"That coffee is light and developed, but baked". - Ok. So this coffee is bright and light, but also suffers from some dryness or ashiness from the bake at the end.
"That coffee is dark and developed". - Potentially delicious. Probably not. This coffee could be intensely sweet and rich with minimal acidity and hopefully not too much ash or typical "dark" roast flavours.
"That coffee is a medium roast and underdeveloped". The most common Specialty roast. It has acidity and is kind of sweet, but isn't rich, unique or satisfying. It could be a little grassy and savoury, or in milder cases it might just be underwhelming and generic. You might also notice some of the underdevelopment identifiers I described above."

#67: Post by **TomC** » March 19th, 2015, 11:36 pm

That's useful to note. What you wrote could be interpreted as unexplained criticism of participants. Thank you for clarifying.

March 20th, 2015, 8:27 am

To all, that was not my intent and I apologize. I sometimes forget the environment I'm in. I own that I am critical of the dark, baked, and underdeveloped roasts that I taste at work but I don't mean that to extend to the online community's home efforts.