I'm after a darker roast

[Craig]

I'm new to roasting and I'm trying to get a roast as dark as the Jeds #5 or #4 I usually use.
The beans I'm using are suitable for espresso and I'm using level 5.9 but the results are more like med-light - not shiny, not very dark and no oil.
Do I try different beans or should I try creating a new profile? Would roasting a smaller batch help?
I'd like to achieve a darker roast with the minimum trial and error as I'm starting to get the caffeine shakes.

[kaffelogic]

The default profile should start showing oil on the bean surface by level 4, so I'm not sure why you are not getting any when you push it to 5.9. Can you post a log file to help me see exactly what is going on in your roaster? Also let me know what beans you are using - that will help me replicate the problem for diagnosis.

[Craig]

Hi
I have tried "Euro Espresso" and "Riviera Blend" from here: http://homebaristashop.co.nz/shop/1kg-g ... an-blends/

I have attached a log from this morning - 100g of Riviera at L5.9 results look similar to the previous roasts which were Euro Espresso

I've also attached a photo of the Riviera roast at L5.9 and some Jeds #4 and #5 (mixed)

Thanks

[kaffelogic]

Thanks for posting both the photo and the log file. That makes it very clear what's going on. There's bad news and good news: the bad news is that you have reached the limit of darkness available on the default profile and the roaster is performing correctly. The good news is that a profile can be created that will meet your expectations. The maximum temperature the Nano 7 will go to is 240⁰C. The default profile reaches that point in 12 minutes and then stops. You need a longer roast period, probably 15 minutes. That is something that I am not very familiar with, but I will consult with some other roasters for some suggestions about the shape it should take and get back to you in a few days with a new profile that you can try.

[Craig]

Hi Chris
That sounds very promising -thanks.
In the meantime I may even develop a taste for lighter roasts.
Cheers Craig

[Simon]

Hi all,
Just joining in to say I would also be interested in a profile specifically for dark/city roasts. Or some guidance on creating my own profile for dark roasts.
cheers
Simon

[kaffelogic]

I am posting two profiles designed to give access to darker roasts. Firestarter does this by lengthening development time, and Steady&Dark does it by delaying first crack. Both profiles will take the roast out to over 15 mins, while Firestarter puts more energy into the roast before first crack. I haven't had the chance to experiment with these profiles so will appreciate your comments and comparisons.

[Simon]

Thanks, I'll try those once my sack of green beans arrives.

[Craig]

Firestarter at L5.9 has a similar look to the Jeds #4&5. It looks good and I'll try tasting some tomorrow.

Steady and dark L5.9 is still quite light.

I have photos if you'd like them - I'll need to use my PC to post them.

I did find about 50 whole beans mixed with the chaff in the chaff collector after completing the above two roasts.

But all in all a great result-thanks.

[kaffelogic]

The beans in the chaff collector happens because the bean density is lower for the dark beans. The same thing happens when roasting de-caff - a fair proportion get into the chaff collector. There are two fixes for that (apart from picking them out of the chaff by hand). One is to make a taller chimney and chaff collector, and the other is to use slightly less fan speed for the cool down. Cool down fan speed is specified in the profile file. Slightly less fan speed should have minimal effect on flavour. The correct fan speed can be worked out using manual control of the fan in timer mode while the roasted beans are still in the chamber, and then modify the profile accordingly.