Rob,

Your book was a paradigm shift for me in the way it organized a lot of thoughts rattling around in my head. The time and attention you're taking to address questions raised here, as well as on your (planned?) blog add even more.

Thanks,
Rich

Hi Rob,

I just finished my copy of your book last night (#26). I really enjoyed it and thought that it's a great resource for intermediate roasters like me. (You skip over some of the basics, which seems reasonable.) I thought you were spot-on with a lot of the observations (e.g. tradeoff between clarity and complexity+body in Maillard phase, bitterness arising from overly fast development interval). Some of the science you brought in was also very cool and, importantly, was actually relevant and applicable.

Anyway, I have a couple questions for you, honestly mostly just about the Loring. There aren't a lot of roasters using it, and probably mostly for that reason, I haven't had many good roasts from one. Theoretically, it seems incredible - repeatable, not prone to roast aromas or scorching, tons of power, no afterburner or cleaning...

(1) What are your thoughts on the nearly pure convection of the Loring? How easy do you find it to generate caramelized flavors without the super hot drum? (2) Also, how does the development phase work with it? It seems that a sealed design might have trouble shedding heat, and indeed I've had a number of baked or aggressively bitter (that overly short development time defect you mention in your book) roasts from Lorings. And, finally, (3) do you notice any qualitative flavor differences between the Loring and more traditional roasters (e.g. a double-wall Probat)? (By the way, you might find a video on this page ( http://nordicbaristacup.com/2014/11/nrf-2014-videos/ ) about differences in reactivity in anaerobic roasts interesting.)

Again, thanks for your writing, and I'll need to order some Nossa Familia coffees soon to see what you and your roaster are capable of.

robhoos wrote:I wanted to take a few minutes to talk with you on HB about your questions. But I also noticed that you live in Portland OR. If you have the chance you should totally stop by the roastery and come talk to me for a bit. If I haven't met you then I would greatly enjoy that, and if I have I am sorry I don't remember it (I'm much better with faces than names). Bottom line is come by M-F 7am-3:30pm and lets have a coffee together!

Hi Rob,

Yes I'm in the Portland area and I'd love to come by sometime to talk coffee! I really appreciate the kind offer and your thoughtful and thorough response to my post and questions. It definitely helps me to understand your book better.

Weekdays are a little challenging for me with work but next time I'll have a day off I'll try to stop by - I'll make sure to send you a PM first. I did have the opportunity to visit Nossa Familia on the HB cafe crawl a little while back and had the pleasure to see your roasting setup and sample some great coffee. Unfortunately you weren't there at the time so we haven't met, but I do look forward to meeting you soon!

Best regards,
Ken

Rob, the following is a particularly helpful clarification that simplifies this aspect for me and seems correct in my limited experience. Regarding airflow, the effect

robhoos wrote:... has more to do with heat transfer and profile shape than it does the flavor of cup, and at the end of the day, flavor attributes that come from different air-flows can be explained through profile changes they cause in my opinion. I know this may be a controversial stance, but in my experience roasting on tons of different systems, and doing flavor profile matching across those systems, airflow affects heat transfer which affects profile which affects flavor.

That explanation suggests why many people have success with a heat gun/bread machine roaster where you're measuring bean temperature and can track it via computer. Heat is applied on the fly, combining fan speed and heat setting, and such roasters are extremely responsive.

Your breaking down phases of the roast by flavor attributes is a much needed contribution and should shorten my learning curve a lot. Thank you also for sharing that Brazil profile. There are also enough profiles posted here and elsewhere by accomplished roasters to get a good idea of where to start, then use what you've written to tune flavors.

So my take is going to be specific to the Behmor with the new board. I've been experimenting using Joe's basic 'recipe' for manual roast, with full heat and fast drum until the start of first crack where the heat is dropped fully and the drum speed slowed for 30 seconds or so when the heat is bumped back up to 50% or so until you get the level of roast you are shooting for. If I read right I'd be better of to smell for the grassy odor and drop my heat a bit, to draw out the 'yellow to 1C' period. This would promote complex flavors over my current attempts. I just got done with 5# of Guatemala Patzun from Sweet Maria's and will likely try 10# of Java Blawan from Happy Mug next. I'm doing 12oz roasts, two at a time, one targeted at espresso and one at drip, so should have lots of opportunities for tests.

I'm also going to be in Portland Monday or Tuesday next week, so may drop by NF if timing works out.

Rob,

I'm going through the book a second time, highlighting and annotating. I'll probably have to go through it a third time and maybe fourth time before incorporating all the relationships. Any chance you'll make some sort of e-book or pdf available before I completely destroy my physical copy? It would be nice to keep tasting notes in the same file as the book.

Happy Easter,
Rich

Hi Rob.

I read and enjoyed your book. Thanks for publishing it. Many of the roasters on this forum and elsewhere have far more experience and knowledge than I. I am fairly new to home roasting and use a heat gun and bread machine with a thermocouple in the bean mass. For people like me (and I am sure there are many), a little more guidance would certainly be helpful. I know there are different roasters, controls, etc, so it is impossible to provide a "one-size-fits-all" profile. I'm mostly interested in roasting for espresso. The below, from one of your earlier posts, is helpful.

So, for the good folks here at HB, here is a general light roast Brazil profile... take it as you will.
Beginning 360 F 50.2lb Charge, Turn Around 145F @ 0:45, Pale white 300F @ 4:00, Yellowing and Hay-like 320F @ 5:00, Brown and Bready 340F @ 6:00, FC 398F @ 9:20, drop 414F @ 11:40. Though I have the data on those roasts specifically, I think this should get you a general ball-park idea of where I am coming from.

In your book, you mentioned you didn't want to tell anyone exactly how to roast, which I appreciate. But frankly, that is why I bought your book and I need some guidance to get into the right ballpark. Some general time ranges (and if possible, temperature ranges, with appropriate qualifiers) would be very helpful. For example, I suspect the Drying Phase can be way too short or way too long, in general, which would lead to obvious defects you mention in your book. Can you provide a typical, reasonable time range for the drying phase (e.g. 4 minutes minimum to 7 minutes maximum)? And the same time ranges for MAI phase and Development?

You also mentioned that dividing the roast time into percentages had some merit. Can you give some approximate percentages for Drying, MAI and Development as a starting point?

I'd still work at using your guidelines to tailor the taste to my preferences. Since you have worked with many types of roasters and have so much experience, I assume some reasonable starting guidelines are possible. This would save a lot of time and help get me on track faster.

Thanks,

Lou

Rob will have a better answer than me, but I'll chime in. A HG/BM can't be charged at high temperature unless you've somehow sealed it for that purpose. Mine just has a lid I lift off with the HG propped in it. Sure, you can pre-heat the bread pan, but that doesn't have much thermal mass compared to other roasters. So your initial stage will be different as you'll be heating up the beans from cold. That hasn't gotten in the way of my getting some tasty roasts off of mine. Other than that first stage once you hit turnaround you could try to emulate roast profiles such as the one he posted and see how they work in your device. It's common that you get to know your own roaster with practice, and that will help you guesstimate how to tweak others' profiles to fit yours.

If you search through the april through September 2014 roast and learn threads, you'll find plenty of profiles I posted using a HG/BM. I generally preheated mine to get a faster start, for what it is worth. Depending on the bean, I would generally spend somewhere between four and six minutes getting to 300F, which I marked as an arbitrary "yellowing, start of Maillard phase" point because I was using a sealed design in which I couldn't look at the beans without dropping the heat way down. Ramp from there to first cracks usually lasted between 3 to 4.5 minutes, and development times ran from 1:30 to 3:30 depending on what I was going for. So hopefully that should give you some boundary parameters within which to explore.

robhoos wrote:Beginning 360 F 50.2lb Charge, Turn Around 145F @ 0:45, Pale white 300F @ 4:00, Yellowing and Hay-like 320F @ 5:00, Brown and Bready 340F @ 6:00, FC 398F @ 9:20, drop 414F @ 11:40. Though I have the data on those roasts specifically, I think this should get you a general ball-park idea of where I am coming from.

It does. But raises some other questions. With a 2:20, 16F Development, RoR through Development and especially from endothermic flash must have been very slow.

• When did 1stC end?
• No issues with stalling?

Rich