Nordic Light

[nrdlnd]

EDIT: I have made many modifications to this profile and it's a long thread. Please look at https://kaffelogic.com/community/viewto ... t=30#p2822 where I have put all together and recommend my last variants of the profile and also some safety recommendations. Always check the movement of the beans in the beginning and don't let them stall!

Hi,
I have worked with a profile that I wanted to mimic Nordic light roasts but still be well developed inside out. It should be a fast roast with a relatively short development time. I've looked at some of the profiles from the more expensive Norwegian Roest roaster. I've looked at Benjamin Fleons excellent Raost profiles for the KL. Some of them are fast intense roasts. I have set the preheat level higher and I have changed the zones and concentrated on the development phase.

I have used rehydrated beans after measuring with a moisture meter and adding water to get about 16% moisture in the beans before the roast. My batch is 95g and if a bean has a moisture of 12% I add about 5g of water to get 16% of moisture. The beans are left to absorb the water at least 8 hours but not more than 20 hours to avoid unwanted growth of microbes. I think the profile should work well without the extra hassle of rehydrating the beans. Please try! My modifications are described in the profile. Default level with a rehydrated bean is around 2.5 and that is a light roast. When and if you try the profile set "L" to around 3.5 and then stop the roast at the DTR or temperature that you want to achieve.

L=2.4 gave a Tonino measurement = 112 and that is on the lighter side of Light (Very Light is more than 115 and is called with the Tonino "Cinnamon"). First crack comes early at around 205 deg C and is very defined. The end weight with this kind of fast and intense roast is higher than with "slower" roasts at least with rehydrated beans. Power requirement is normal well below 1.4 kW. If you want to achieve "Cinnamon" you can try a lower DTR and end temperature. It's not possible to try to achive the same end temperatures as for example the Roest roaster as the temperature is measured differently. The KL has a higher fan speed so the "bean temperature" will be higher as it measures more of the hot air! Neither is more "correct" as it's not possible to measure the temperature inside the bean!

I show the log of a L=2.4 roast. I tasted it 1½-2 days after the roast and it had a balanced acidity, a lot of aromas and sweetness. It's not "baked"! I tried it as "drip" coffee. The bean used is a Sidamo Wendo Gr2 high altitude and washed. It's a hard relatively small bean. More delicate naturals may need a lower preheat.

220716_SidamoWendo_NordicLight_2.4.png (77.54 KiB) Viewed 8988 times

This is the profile. It may need more work with zone 2 and 3 at the end depending on the bean. Please give feedback if you have tried the profile!

NordicLight.kpro

(2.79 KiB) Downloaded 505 times

[Mohamed Anwar]

Thank you so much for the effort you made with the profile. I have a question please. the coffee I'm using is a fermented one, cracks at 215C always. would you recommend using that profile with it to achieve a light roast for filter? and which level should I aim for?

[nrdlnd]

Thank you Mohamed for your kind interest!
I actually don't know. I've had a fermenterad from Colombia and FC varied depending on the profile from 207°-214°C. I never really liked that expensive bean but I may have some of it left and I may try it again but as rehydrated! I couldn't measure moisture by then. My experience is that FC tends to come earlier with a bean with a higher moisture but not always. Interesting if you try the profile with a batch not bigger than 100g as it depends on the batch size also. You could try a DTR around 22% and an end temperature around 214°-215°C. I think that's about L=2.5 with this profile. The roast degree is very much up to your own taste preference. I haven't tried the profile with a higher "L" so I don't know. It's open for your own experiments.

[Mohamed Anwar]

Thank you so much. Please join us in the discord group. We are a big community of owners there.

The link of the group is on the facebook group of KL.

[nrdlnd]

I'm sorry but I rather don't want to join another group. I don't use Facebook either because of their policies.
This KL forum is enough for me and it's also possible to contact each other privately within this forum. I think the development of the KL roaster is more benefitted in this open forum rather than in a closed group. I'm "old school" and I may be wrong. If you think so you can always try to convince me!

[nrdlnd]

OK Mohamed!
I should thank you for the invitation! Forgive me for my comment above! I still prefer comments in this forum that I use to follow. But if you want me to join the group on Discord you must send me an invitation privately. If I can be to some help I'm open for that and of course I could also benefit from the the group.

[nrdlnd]

I must show you this example how a small modification can change the result at least "on paper" as I haven't tasted it yet. My initial thought was that the best was to just supress a flick at the end but then let it go without modifications and let the exothermic reaction do it's work. The roast I made with Nordic Light a couple of weeks ago (picture above). The taste was ok but it still had a flick at the end on the ROR curve.

I roasted it today again but now I extended the negative zone 3 to 5:40 to supress the flick. This is the result:

220802_SidamoWendo_NordicLight_2.6.png (81.74 KiB) Viewed 8685 times

The ROR curve looks even "better"! The bean is not a single origin. It's an Ethiopian Sidamo Gr 2 washed high altitude but of decent quality. Heirloom. High altitude and a hard bean. I had rehydrated it to 16% moisture. L was 2.6 and in this case it's a light roast. It's developed with a DTR around 21%. I haven't measured the roast degree yet but it's light visually.

The profile is the same as above but with this small change added. It works with this bean but another bean may need other modifications. Here is the profile but you could as well just extend zone 3 to 5:40 if you have already downloaded it. The profile has the same name as before so if you downloaded the first version it will be overwritten if you don't change the name.

NordicLight.kpro

(2.85 KiB) Downloaded 359 times

[nrdlnd]

I have a comment about the profile. I have tried it with some other beans. A washed very high altitude SL-28, SL-34 from Uganda and also with a single origin natural from Guatemala. These two beans need changes of the zones. The Uganda setting zone 2 to zero (no zone) and the Guatemala natural maybe also without zone 2 and also especially let the zone 3 start later to avoid a dip. The profile MUST be adapted to different beans as everything is happening very fast especially at the most important end of the roast.

The profile worked very well with the grade 2 Sidamo Wendo as I've showed above. For naturals (and maybe also for bigger beans) that seem to need a more gentle and longer roast I still have the best results with my modified D-Light profiles called DLightR3fanmod (https://kaffelogic.com/community/downlo ... hp?id=1212) and DLightR4fanmod (https://kaffelogic.com/community/downlo ... hp?id=1229). I think the original Damian profile is equally good if you have enough voltage. My modification of his profile is mainly a modification of the fan so it needs less voltage. It still has a rather high fan speed. Most of the time I rehydrate my beans before the roast but the profiles seem to work equally well without rehydration.

[nrdlnd]

Hi again!
I've had some success with this profile but it's not for all beans. A safe bet is the common washed Grade 2 Ethiopian beans from the Sidamo region. A similar bean I've had success with is the Limmu Kossa Sakka from the Limmu region. It's also a Grade 2 and washed. My regular batch size is 95g and I moisture them to about 16% moisture. That usually means from 5-7g of water (dependeing of the moisture of the bean) at least 8 hours before the roast and not more than 20 hours before the roast.

These beans are on the smaller side. I had an accident with a bigger bean. I got a fire or actually a glowing in the chaff collector. This was because the fan speed was not fast enough in the beginning of the roast and the bean movement stalled. I made some changes to the profile. I raised the fan speed in the beginning and I lowered the preheat. Now the movement is better. Another possibility could of course be to have a smaller batch size but I didn't want to change that.
This is the modified profile now called "NordicLight3". I recommend it instead of the earlier variant. I usually start with a L=3.5 and register 1st crack and stop at a DTR around 20-23%.

NordicLight3.kpro

(3.11 KiB) Downloaded 303 times

A couple of examples of roasts I made today with an Ethiopian Limmu Kossa Sakka and an Guatemala Antigua. I blend these roasts fifty-fifty. I'm still drinking a roast I made two weeks ago and it's very nice. It's a light roasts on the Tonino scale almost very light. I drink it as filter coffee. Comment: Zone 2 and 3 has the same negative value. I could have used just a single zone but left it as it is was as it makes it easier to make further compensations. The first log looks very nice but the second Antigua may need some small changes at the end then it's good to have two different zones to play with. Edit 221105: Since a couple of days I'm drinking a fifty/fifty blend of the two roasts below. They are not "single origin" but from a region. Both are from high elevations and washed. I measured the roast degree of the blend with my Tonino. It was 111. More than 95 is a light roast and more than 115 is a very light roast (Cinnamon). It's very nice as filter coffee. In the same time sweet and with a nice acidity. Maybe not so much "body". No bitter aftertaste. Very easy to drink!

221030_LimmuKossaSakku_NordicLight_2.2.png (70.59 KiB) Viewed 7708 times

221030_GuatemalaAntigua_NordicLight_2.8.png (72.87 KiB) Viewed 7708 times

For more gentle beans and if they are bigger I still use my less power hungry modification of D-Light with a lower fan speed. I've found out that the fan speed still was too high at the end of the roast so I've lowered it a bit more. It has still a high fan speed. I'm calling it "R5" now and it's my preferred variant of my modifications of D-Light. If you still run out of power at the end of the roast (depending on your voltage) it's possible to lower the fan speed even more at the end of the roast. I have roasted some exquisite naturals from Ethiopia and Guatemala with this profile and blended them fifty/fifty. I've got high ratings for these blends. It depends not only on the profile but more on the raw coffee. The Ethiopian was a Guji Anasora natural and the Guatemalan Finca El Socorro also natural. Both single lots and highly rated. They worked well with "R5". For what it is but a chef on a gourmet restaurant where I live tasted this coffee and said it was the best coffee he had ever tasted! I may try these beans with NordicLight3 above with it's lowered preheat and raised fan speed in the beginning of the roast and compare.

DLightR5fanmod.kpro

(4.58 KiB) Downloaded 293 times

Edit 11th of December 2022: The above roasts I blended 50/50 (washed Ethiopian Limmu Kossa Sakka Grade 2 95g + rehydration 6g and washed Guatemala Antigua 90g + rehydration 5g) has tasted very good - one of my best. Because the Antigua is a bigger bean I lessended the batch to 90g for this bean to make the initial movement of the beans faster. I measure the moisture of the beans and in my case the amount of water I rehydrate 8-20 hours before the roast varies between 4,5 and 6,5g. About blends: The above blend has been very successful for me and taste better as a blend with a fuller richer taste. Sometimes a blend taste worse than the single coffees. With a recent blend I got a bitter aftertaste that I couldn't find in the single coffees. I can't explain why!

[nrdlnd]

I have got more experience of the profile now and I have also tried on bigger beans from a lower elevation. My first attempts were with smaller harder beans from Ethiopia and fully washed. The first variants worked best for them with a higher preheat and with a lower fan speed in the beginning. This is an example from today with a washed Sidamo Grade 2. I think the ROR looks OK and I don't think it's a crash. It's fully developed with a DTR around 22,5%.

230102_SidamoGr2_NordicLight2_2.png (76.68 KiB) Viewed 7038 times

This is the profile:

NordicLight2.kpro

(2.93 KiB) Downloaded 263 times

The last changes of the profile version 4 with lower preheat and a higher fan speed in the the beginning has worked well with bigger beans and from a lower altitude. This is an example:

221220_IndiaKalledavarapura_NordicLight4_3.png (73.94 KiB) Viewed 7038 times

This is a washed bean from India from an altitude 1150-1400m. The batch was 90g instead of 95g with the smaller bean above. The preheat is also a little lower and the fan speed higher in the beginning for better movement. It got new life as a relatively light roast. I think this could work with beans from for example Brazil. This is the profile:

NordicLight4.kpro

(3.11 KiB) Downloaded 301 times

Caveat! I haven't tried these lighter roasts as espresso only for filter coffee. They are sweet and not bitter. My grinder is an Option-O P64 with MP burrs (Unimodal). I think these roasts could work well for espresso if you like light roasts.

I have not modfied the L-scale so it doesn't give the correct roasting degree. I measure the roasts with a Tonino and they are almost always light or very light. I start with a "L" around 3.5 or sometimes more. I register first crack and aim for a DTR around 20% or sometimes a little more and stop the roast manually. End temperature is around 215 deg C or sometimes a little more. The development is fast around one minute and 15 sec sometimes even lower.