farmroast wrote:I have changed my approach and have been liking the results. Lower and slower ramp to 300f BT. Ending up with a lower ET at 300f BT. At about 285f BT I'm increasing my heat input much more making a steeper ramp 2nd leg but still ending up with about the same ET at 1st crack. I did a city+ roast of Ethiopian Bonko DP and pulled a shot yesterday with the Cremina. Sweet and totally fruit jammy, the lemoniness was just right. By far the cleanest, most balanced, lighter DP roast I've pulled.
cheers,
farm

Ed,
I was just getting ready to start this thread when I saw your post. Nice observation.

I changed my drying phase method from a low charge temperature and slow drying ramp up, to a higher charge temp and faster ramp, hitting 300 degrees at 4 minutes. The results were a poorer tasting roast. The other problem created by the high ET charge and fast drying phase ramp was bean color often seemed to go from a greenish yellow to a light brown without ever hitting bright yellow.

Fullsack wrote:Ed,
I was just getting ready to start this thread when I saw your quote. Nice observation.

I changed my drying phase method from a low charge temperature and slow drying ramp up, to a higher charge temp and faster ramp, hitting 300 degrees at 4 minutes. The results were a poorer tasting roast. The other problem created by the high ET charge and fast drying phase ramp was bean color often seemed to go from a greenish yellow to a light brown without ever hitting bright yellow.

Doug,

Did you see that at all finish roast levels, or were you working at a particular level?

My observations to date have been similar to yours--worse taste with roasts where the initial ramp to 300°F was less than 5 minutes. I think that had me drop the charge temperature about 25°F or so, at least, but I'm not sure as I made the switch just about the time I added thermocouples to the hottop. Previous charge temperatures were based on the hottop display vice an internal thermocouple--which is why I'm not exactly sure.

Chad,
The ideal time for the drying phase is going to be bean specific, the same may go for charge temp. Shorter ramp time for the dryer beans, so I wouldn't use time as a guideline, but rather use the bright yellow bean color. To make the point clearer, I should have stated slower ramp to bright yellow staying under 300 degrees bean temperature.

Depending on bean, my general approach now is the darker the roast the shorter the time to 300f and the higher charge temp. Conserving more moisture for the darker roasts only. Extra drying and lower charge temp. for city+ or lighter

More isn't always better I pushed the drying period to 5:30-6:00 minutes, to yellow and got 2 flat batches of Brazil and sour and grassy Harar and Sumatra. For my roaster, 4:30, 295 degrees is the drying phase sweet spot with these beans. It seems to be the case, even though these beans have different moisture contents. Not sure why that is.

For the charge temp, I changed to 250 from 300 degrees. Maybe a 275 charge will be the ticket.

Good point Jim, my assumption harder beans would hold a different moisture content than softer beans is off base. Porosity isn't really the issue.

This has been a great topic. Using an RKDrum, I have not been pre-warming the drum for fear of scorching the greens. But I guess that this will not happen as long as the charge temp is around 300 F. I am also a little cautious because the drum is not spinning while being loaded. However, I will try this for some roasts as I have found that my lighter roasts do taste flat, grassy.....baked? Nowhere near the fruit tastes as others have found.

So, how would this sound for something like Ethiopia Idido Misty Valley:
1# in drum charged to 300F
Proceed back to 300F over 4-5 minutes
Increase heat to start FC at 8 minutes and done by 10 minutes
Continue for about 1 minute for a city+ roast at 435 F bean temp

Any feedback greatly appreciated.

Dave