Dang Samuel - dropping some knowledge on me! THank you!

I think my first couple roasts I was using pretty dense beans that needed alot heat. Ironically, I just got done roasting a more "normal" bean in the quest - colombia timana principal lotes (before reading this post). Coincidentally, I ended up using Samuel's suggested amp range for both these roasts. First one I actually was carrying too much energy through first crack - I'm guessing thats gonna be a little dry. 2nd roast I was able to manage the energy much better by backing off the amps and applying more fan earlier. We'll see how it cups.

175g charge on both roasts. Tried to use low fan (2.8-3.0). Only going to 4-5 midway through maillard. Amps were in that 8.5-9.5 range in both roasts. Got to 300 well before 5:00.

sidenote - the sumatra aceh ended up brewing a little too roasty. However, when I combine it with one of the "lighter" uganda roasts I did, its actually a pretty satisfying cup!

I did 4 roasts last night, with different profiles, and I cupped them all this morning. Here are the results.

This is a Washed Ethiopian Yirg, from Happy Mug.

The first profile is my standard style, the only difference is I was actually using the trier and looking for an even bean color during development, which lead me to develop long then I probably would have. I was a bit worried I would get overly roasty notes.



For my next roast, I had been chatting with Thepilgrimsdream, and he described his roasting method on his gas roaster as follows:

"I charge my roasts with 25% Gas(or heat application). Between 1:30-2:00 I add 100% of my highest heat application for that roast. I don't touch the gas until about 20f after my coffee turns yellow(unless my roast runs off course). Then I back off slightly. I back off about 12-15f before FC and don't usually touch the gas again. So I make 3 adjustment every single batch." - He uses a fixed airflow.

You can see my MET went much higher then normal so I was concerned there as well.



Next, I tried a "set it and forget it" style. On my quest, I know that 77 amps is the lowest amps I can go to not stall through first crack. So I put my fan on 4 and let it ride. It was interesting to see how the MET spiked at the end, but due to my small probe, you can see my BT flattened from 1C.



Last, I've been doing a lot of browsing on Crown Royals coffee. Jen, posts her roast profiles. So, I went to a washed Yirg that she roast and attempted to follow her graph. I started by looking at what her first crack was, and what mine was. I saw my reading were 31 degrees lower. So I did the math and adjusted accordingly. I saw she goes through the drying stage quite quickly, and I knew I would need to up my charge temp to mimic that. I know she uses a fixed air flow as well, so I set mine to 5. I was extremely pleased that I was pretty much able to nail the profile and it also looked good with a steady declining ROR.



..........................................

Morning time and tasting.

I was very excited to try my new roasts, but I knew that I would have bias, so I cupped them blind. Here were the results.

Cup 1 (Jen style)
Immediate astringent bitterness. some subtle sweetness on the finish, medium acidity, muted origin flavors.
I was really put off by the overwhelming astringent bitterness here. I rated it at a 1.5/5.

I was pretty surprised and kinda disappointed. I will probably try this again, but lower my airflow. I don't consider 5 to be too high, but maybe im wrong.

Cup 2 (Pilgrim)
Bitterness was a tiny bit astringent but much less then cup 1. This cup had the most acidity, and a clean finish. Very compact cup. Hits you up front with a little bitterness and pronounced acidity, some fruit and flower mixed in (most origin flavors), then goes away.

I liked this cup as a tasting cup because it had that pop of acidity, but It was very compact and sharp. I dont know if I would want to drink an entire cup of it as it would probably be a bit to acidic. Also I would like the flavors to stretch out more. You can see the middle phase/ramp phase was super short, so I would try to stretch that out more.

Cup 3 (set and forget)
Thinner body, slightly watery, but not too much. Medium to high acidity. Subtle sweetness and a clean finish.

This cup while flatter, was the least offensive lol. It was a bit watery, but it had enough acidity to keep it interesting. I guess it had the best drinkablity, however, I would prefer more body, sweetness, and clarity of origin flavors. I did not get too much astringency here, maybe I should keep my airflow at 4. I gave it a 4/5.


Cup 4 (My way)
I hate to say this, but the origin flavors/acidity taste reminiscent to cat urine. It's kinda broth like too. It wasn't very sweet, and kinda flat. It did not taste burnt or over roasted at all. I rated this one as a 2.5/5. With those descriptors, you think it would rank lower, but I guess they went as over powering as some of the other off flavors.


Oh well, I will need to review this post before roasting this coffee again. I think I will lower my airflow, and try to stretch out the middle phase a little bit more. And, I'm not sure when to drop. lol.

Very interesting post... so many questions. partly because my initial testing from the quest is so different than what I've been used to on the huky.

Take this with a grain of salt because heck what do I know... but I'd actually STRONGLY advise you to not try to mimic profiles from other roasting machines. Your quest operates so differently from a gas machine. And one gas machine operates so differently from another gas machine. Heck even with my huky - the same temps and curve result in dramatically different cups depending upon just the amount of airflow I'm using.

I haven't used my huky since I got the quest but they are SO different - the "rise" in temperature during development on the quest is so shallow in comparison to what a gas machine such as the huky prefers (IMO). SPeaking of which, can you adjust your artisan logs to show what you really dropped the roast at? What I mean is if I'm hitting first crack at 388-393 on the quest... going much past 410 seems to really make the bean chalky tasting. On my huky, I'd hit first crack at around that same temp, but if I dropped at 410 or really anything less than 415, it would be amazingly underdeveloped and gross.

Before I got the quest, I would look at other quest profiles (like yours for example) and see the total temperature rise from first crack to drop is like 3-5 degrees - um what? How can that result in anything beyond tasting like hot dot water. Now that I have a quest, those small temp increases in dev actually seems to be preferred. I wish other quest users would join this thread because this "low temp rise" from fc to drop has me completely baffled, I don't understand the science behind it. IF you look at common roasting resources like sweet marias for example, the time between FC and even a light roast like city/city+ should have a MUCH greater temp swing.

https://legacy.sweetmarias.com/library/ ... gree-roast

Those numbers DO compute pretty similarly to roasting on the huky.


WHat mods do you have to your quest again? Reason I ask is because you hitting dry at 3:18 is equally baffling to me - my quest couldn't dream of hitting dry that fast. You hit dry that fast with 8.0 amp and 5.0 fan? My lord that's crazy. Even in this case where we both have quests, I don't think our profiles would even match up because its obvious we have QUITE a bit different quest m3 machines...

I'd like to see Pilgrim's profiles that he's done on his quest (not his pro gas machine). His roast theory is interesting and we've chatted before as well; I believe Deaton Pigot spoke of a similar concept. It worked well on my huky, making for much sweeter and vibrant cups but I now realize I was using too much airflow on my huky. It'd be interesting to revisit with a lower airflow level, more like what Henry Chang has advised.

I use the same roast formulas for production and sampling(on the quest).

I have the new style drum and the vent by the fan bent out, so I'm thinking my airflow is higher than yours (my MET is lower).

Anyways, is the bitterness an acid bite? Or is it more smoky?

If it is smoky, I would recommend increasing the airflow. The MET suggests your airflow is lower than mine.

If the acidity is too bright/sharp, you could wait a few days to brew (I generally like 7-12), but increasing your brew ratio helps too (17:1 drip), (2.5:1 espresso).

On the quest - What is your air flow during drying/maillard/dev?

What time are you generally hitting FC at?

How much is your temp rising from FCs to Roast end?

This would be super helpful for me if you could comment on that - thank you!

I've moved to high fixed airflow thru my whole roast. Variable airflow is more forgiving, but fixed is more repeatable. You just have to experiment

Dryness/low aroma = too much air
Round but smoky/dirty finish = too little
Sometimes too little can lead to underdevelopment

I generally hit FC between 8:00 and 10:00 dependant on the coffee. And then maybe 0:45-1:30 of development dependent on the coffee.

I go up usually 7-15f past FC. Maybe 14-16f/min avg. for more fruit. 10-14f/min more caramel/muted acidity

I'm moving away from Deaton's roast theory of increasing gas, but I think we both end up approaching FC at 20-22f BT delta. This is important to achieve desired sweetness/acidity.

I've tried Deaton's theory and recently have been chatting with one of Tim Wendelboes roasters. The result has been ending up with a more linear profile with still a constantly decreasing ROR, it seems to get better development with more fruit/clarity.

Fascinating.....

To slam into FC at 20-22F ROR I'd need my quest to be at 10A (at least) and I believe I'd have to have increasing ROR at around 300F. I'm actually not even sure that's possible as I'm dropping to 20F at the end of dry. To sustain the energy required to hit FC at that temp and still have a decreasing ror, I think I'd have to be hitting FC at like 6-7mins. I'd love to visually see one of your artisan curves if you actively log your roasts. I also think high airflow in the quest would result in too low of MET and I'd struggle to even have enough energy/heat to complete a roast, let alone slam into FC with that level of power.

High airflow = over 7? Over 8?

Final question - what kind of water do you use with this roasting style?

For what it's worth when I was using higher airflow on the huky - it made the roast curve approaching first crack like a raging bull, constantly trying to tame the temp fluctuations. When I started using low air flow, it was FAR easier to have a controlled drop and dev phase. I believe if you do use high airflow, you need to have high heat to develop thecoffee properly. When I did the low air flow huky roasts, I didn't need nearly as much heat to produce good flavors.

The quest - I have no idea what's going on lol.

Remember, the Quest has a little dinky computer fan. It's a pretty low airflow unit to begin with. Probably a lot lower than the Huky. So 7 or 8 isn't unreasonable. And yes, I use a lot of heat applications and smaller batch sizes. I finish with close to 40-50% of my total heat application usually.

If you don't apply much heat til around 1:30 it gives you a lower turning point, from there I slam it with a lot of energy. Giving me a high BT delta while still stretching out the drying phase. Rao talked about "soaking", in one of his recent blog posts, we might do it for slight different reasons though. Works for me.

I've been experimenting with Third Wave Water and the recipe Matt Perger posted. Sometimes I use Poland Springs if I'm lazy.

Honestly, I mostly just sample roast with the Quest 100-120g batch sizes. And I log with paper. I'll maybe snag an amprobe and bring it home with me to record some Quest batches

Are you describing your quest roasting in this post, or your gas roasting? Sounds like gas roasting. ex: hitting the"heat" at turning point isn't going to do anything on the quest for a little bit because of the obvious lag in electricity vs gas. The quest doesn't have enough power IMO to have low heat until turning point. The quest fan is dinky, but so is it's corresponding heating element. Using the quest at a fan setting of 7 or 8 is going to drop MET so much that the roaster isn't going to retain enough heat to be able to drive energy into the beans IMO. Huky's fan has a broader spectrum of "power", but so does it's heating element (gas stove).

When you say you finish, do you mean when the dev phase starts? or when you're dropping the roast?

I haven't tried a quest roast at lower than 150g. I've been doing 180g charges. Would love to see the curves with your quest. It's fascinating that you can use similar roasting methodology in the quest because it seems far far different in operation and results than a traditional gas roaster, or even a smaller gas roaster like the huky.

Remember, the Quest has a little dinky computer fan. It's a pretty low airflow unit to begin with.

This is an interesting thread which I've only been lurking on, mostly because I long ago gave up trying to understand the nuances of my Quest MK-2 after finally getting my roasts to the point where I like them. Indeed, I've even given up Artisan, using only my EricS probes and the bare data logger as a readout. I really appreciate this quote...took me ages to figure out why the Quest flavours were so much different than those of my air roasters, from which I moved to the Quest. I believe this is a very important statement in understanding the original Quest (heavy drum, trier on the left) and the Mk-2 (lighter drum, trier on the right). These are predominantly conduction roasters through which there is not much air flow. The air flow is just enough to remove chaff and smoke when cranked up to high, and fine tune the ET...that's about it. The dinky little fan draws a vacuum in the drum at the end of the charging chute, and what little air flows is drawn into this vacuum at the front and the back drum gaps. You can't compare profiles on this roaster to Quest-S (perforated drum), or modified Quests (with drilled or shortened drums). And one most certainly cannot compare any of these with larger roasters with beefy fans. It nearly drove me crazy trying to regain the brightness that characterises most fluid bed roasts, until I figured out that conduction roaster roasts are simply different. To me, at least, there is a characteristic flavour difference between different kinds of roasters, the fluid beds at one extreme and the conduction roasters at the other. Once I gave up trying to duplicate the 'recipies' and profiles posted by others, and just manipulate my Quest until I found roasts that I liked, I was a much happier fellow. Until then, I almost gave up on the Quest. I'm glad I didn't.