amh0001 wrote:

Adam sent me two coffees, I believe these two to assess. I figured I'd just post here so there's more feedback and people working with the Quest (especially with BT2 rather than BT1, since BT1 is way more common) can have more reference points. By the way, I haven't looked at these graphs until now - I was assessing blind.

I brewed up both as Perger-style v60-01s, 12:204, 204F, bloom 40s, first pour @40s, second pour @1:15. Both finished at around 2:20 (2:21 and 2:19 for the Colombia and Costa respectively). Both batches' beans broke pretty easily and looked reasonably well-developed internally.

The Colombia TDS'ed at 1.27, for an extraction yield (EY) of 20.1%. Sweetness was well-developed, and the coffee's not baked. I immediately noticed a cigar-distillate flavor - I don't think this is scorching, but rather just a roast that went too dark (for my palate, and I think for Adam's based on his comments). It's a little lemony, and there's a fermenty-berry thing going on (a green coffee issue/bonus, depending on your perspective). I'd probably just try roasting this slightly lighter - back off on heat a bit faster in development, and you'll get rid of the smoky character.

The Costa TDS'ed quite a bit lower at 1.14, for an EY of 18.1% - probably this coffee is a bit underdeveloped in some sense, or at least it's not very soluble. It's also quite sweet, and cleaner than the Colombia - that smoky-cigar-tobacco aroma is present but very minimal. It's a simple cup, but a good one. I think that's just the green coffee, not roasting. This one is slightly the opposite of the above - probably needs to be pushed a little harder than the one above.

It's pretty interesting how little increase in temp BT2 shows in development - it's a really light probe with very little thermal mass. When I've worked with it, I was surprised how BT1 could show a very pretty roast when BT2 - with less smoothing, in some sense, since it's so light, and less momentum - would show a sort-of stall.

Perhaps also try experimenting with fan settings? Though if you've already done the Rao lighter trick, you're probably close enough. That's just another potential source of smokiness.

I actually think these roasts are pretty competent - I've been served worse on many occasions. I'll update this post with further thoughts over the next few days.

amh0001 wrote:WEll,

After about 7 roasts, 3 of them in the trash, I'm getting pretty frustrated. I haven't had a good homeroasted cup in a while either.....

Tried to follow happycats instructions.....tough because of my alt BT probe, If it give it more heat in the middle im getting FC around 6 mins, roast smells smokey.

Tried following Jim S instructions...scorched and crazy graph.

Tried doing some of my own ideas.....meh

I just dont understand what is so different about my quest, and why it is so hard to get a good roast out of it. Hopefully I get this figured out before I throw in the towel.

Thanks everyone for all the help........

Sorry it didnt work for you.

Point of clarification... Is power off between charge and turning point? My power is 10 preheat, off after charge, 10 at turning point, then bleeding off after peak bean temp. That doesn't seem to match your description of "more power" half way through.

I do light roasts so they are never smokey.

I bet if you were able to get together with a local home roaster things would become clearer.

Yes are there any roasters in the North LA area?

But I do have some good news! This morning I had a 4.5 out of 5 cup! Here is what I've figuring out.

MET: Seeing as I have BT2 and I get different readings. I decided to follow MET rather then "8 amps here, 6 amps there". I also realized then when people were suggesting a hot charge IE 400+ BT, I was actually much hotter because my BT2 sits lower in the drum. Focusing on MET helps with all of this.

BEAN QUALITY: Even though a lot of the unwanted flavors I was getting I attribute to the way I was roasting. You cant expect amazing coffee with meh greens.

This morning I had some Ethiopa rated at 92. During cupping it tasted like Brisk lemon Iced Tea. Tasting in pour over, it is chocolaty, sweet, and has lemon tea in the background. I was really happy thinking this cup. Here is the sloppy graph. I think I did use some fan in this roast, and I'm not sure how important that was. I find fan is a good way to move heat around and make your amp changes happen faster. I need to keep experimenting. I roasted 6 coffees in a similar fashion. There was little to no Tobacco flavors present. Some where papery and dull, but I feel thats because I'm still getting control of the process. I am going to keep roasting this way and see what I can find out and report back.



I don't feel as if i'm completely THERE yet, but I feel like i'm getting closer. I really appreciate everyone that continues to read and has offered their wisdom.

AssafL wrote:Sometimes smoky notes come from burnt skins accumulating under the drum. Perhaps see if it needs cleaning?

+1

After I found a very high wattage vacuum cleaner that I can insert in the small hole in the back of the drum I have had a dramatic decrease in smoke, much cleaner roasts.

amh0001 wrote:Yes are there any roasters in the North LA area?

But I do have some good news! This morning I had a 4.5 out of 5 cup! Here is what I've figuring out.

MET: Seeing as I have BT2 and I get different readings. I decided to follow MET rather then "8 amps here, 6 amps there". I also realized then when people were suggesting a hot charge IE 400+ BT, I was actually much hotter because my BT2 sits lower in the drum. Focusing on MET helps with all of this.

BEAN QUALITY: Even though a lot of the unwanted flavors I was getting I attribute to the way I was roasting. You cant expect amazing coffee with meh greens.

This morning I had some Ethiopa rated at 92. During cupping it tasted like Brisk lemon Iced Tea. Tasting in pour over, it is chocolaty, sweet, and has lemon tea in the background. I was really happy thinking this cup. Here is the sloppy graph. I think I did use some fan in this roast, and I'm not sure how important that was. I find fan is a good way to move heat around and make your amp changes happen faster. I need to keep experimenting. I roasted 6 coffees in a similar fashion. There was little to no Tobacco flavors present. Some where papery and dull, but I feel thats because I'm still getting control of the process. I am going to keep roasting this way and see what I can find out and report back.

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I don't feel as if i'm completely THERE yet, but I feel like i'm getting closer. I really appreciate everyone that continues to read and has offered their wisdom.

Adam,

Great to hear you are getting close to that 5 level roast, and I'm commenting to help bump this thread back up, as I am really enjoying reading along and trying all the great suggestions.

Funny, I have just finished 6 batches of a SM Colombia and used the same hot charge roast you show above in your graph. Very excited to cup it later to see the results, but it is the best declining RoR I have ever had.

Interestingly, I have a print out of notes from Another_Jim's old original comments from how to use the Quest, with settings , times, event points to use as a guide. I had always had trouble hitting those markers. But I noticed my roasts today hitting them one after another, a good sign!

Keep up the posts on your results, I enjoy testing the suggestions along with you.

Bak,

Thank you for the kind words. I am very happy to hear you enjoy the thread and are roasting like me! Please do report back with tasting notes and graphs. I am currently roasting some batches, but I am changing my charge size down to 125 grams to see how that will affect the results. I found that a drying phase of 450 was good to not scorch the beans as much, but also was heating a bit too slow hitting 300 around 5-6 mins.

Rgrosz,

I understand why my graphs look different in that aspect. It is because I am using a very thin prob that in through the bolt in the sight glass window. No Stream talks about this in a post above. I was worried about it in the beginning but now I know its because of the probe. I am actually probably going to order the BT1 probe from Eric just to have some reference to other users.

I will post some graphs and updates soon.

Just an update of where I'm at.

I have at least stopped most my roasts from having that tobacco flavor. I believe the causes were two major things. Too high of temps. My BT probe is much lower in the drum and I cannot compare that to people with BT1. I try to focus on MET. The other factor is green coffee flavor. I had bought 5 lbs of Guatemala to practice roasting, and I think that on top of getting too hot, I just didnt care for the coffee.

I am after a specific flavor that I got in a green coffee from maui (that 5 of 5 cup). Overall sweetness with a touch of acidity that tightens the tongue just enough to make your mouth water and comeback for another sip. WIthout any bitterness or burnt flavors. Also I have been getting really good coffees from Eithopia (yirgs) that have amazing florals and fruits, however I am not roasting them the best to bring out those flavors correctly.

Most my coffee has been over roasted leading to burnt flavors, and muted flavor notes. For instance here is a La Minita Coasta Rica coffee. I have been trying to focus on getting a nice declining ROR and a nice decline after 1C. I was really happy with the look of this graph! I tried holding my MET at 490, because of how it influences my ROR.



I felt that this graph hit a lot of points that are suggested for a good roast.

1. declining ROR
2. 300 BT around 4 mins
3. Total roast time around 10 minutes
4. a development time around %20

The graph looks pretty nice. The problem is the cup tastes super FLAT (like the MET line). I dont get overly roasted flavors. I dont get baked. I just get muted flavors that leave the cup tasting super flat and boring. Underneath in there I can taste there is greatness in this coffee, it has hints of the sweetness and acidity im looking for. I tried messing with my grind to see if that would make a difference, I got a TDS of 1.4 (using a brix refractometer from my homebrewing days, multiplied by .85). I can tell the coffee is not under or over extracted, just flat boring.

I think this makes sense as there is not really a RAMP in the roast. I'm not too sure how to make this better.

I would think in order to give the coffee a RAMP I could dry around 450 and ramp to 500(MET) to finish out the roast. This is has been my go to method trying to emulate NoStreams graphs. But I find I get sagging in the middle with ROR, and an anemic 1C, with overly roasted flavors. I wish I could just get this Ironed out and get that great cup.

Here has been some of my other roasts.



This is a Ethiopian Yirg, from Sweet Marias. A 92 point coffee. I tried charging at 450 MET and then ramping at around the 3 min mark, then hitting with some FAN while keeping it under 500 MET. backed off the amps during first crack to get a declining ROR during development. I think once again its a nice looking graph.

Tastes in the cup, SO flavors are muted and flat, overly roasted with some burnt roasty flavors. hints of florals and fruits in the back, but not sweet or clear.

Im really interested to see what peoples thoughts are.

Cheers
Adam