Consistency problems with Ethiopia Yirgacheffe

[BikeNerd]

Has anyone had any issues with creating an overly acidic yirgacheffe? My charge temp is and has always been at 420 for this bean. The completed roast is around 12 min ending at 415, in the middle of first crack finishing in the cooling tray. I'm wondering if my charge temp is to high? I've also used the same profile and achieved amazing results. I'm roasting on an electric 3k us roaster with airflow all the way open for the entire duration of the roast.

 

[MSM]

If you are experiencing more acidity than you like by ending first crack in the cooling tray, try pushing it to the end of first crack in the drum then dropping it into the cooling tray. This will help balance some of the organic acids with the natural sugars. Citric acid in coffee is usually maximized just before first crack. So keep that in mind as you push it into a stage of sugar caramelization or organic degradation beyond first crack.
If you are experiencing too much acidity, it simply sounds to me like you are not developing it long enough. It really wouldn't take much. You can start with going 30-45 seconds further in the drum. It does depend on your rate of climb once you hit first crack, but I would recommend going to 420 at first and tweaking it from there.

 

[peterjschmidt]

Good advice MSM.

 

[CoffeeJunky]

When coffee is under roasted, it will have higher acidity. When i was in Chicago few weeks ago, most of the roasters were pushing for the high acidity and they called it very fruity. I didn't like that but I guess many of the small artisan roasters pushing that taste in their coffee these days.

 

[RedCup]

I charge Yirg at 380 (5.5 lbs Diedrich) and pull at 410 which for me is right between 1st and 2nd. I get much more of the "Blueberry" aroma if I push it past 1st crack than I do if I pull earlier. A faster roast seems to work better than if I prolong it.

 

[BikeNerd]

Thank you guys for the replies. I will try some modifications today and play around with charge temp and drop times. Thanks everyone.

 

[JumpinJakJava]

Good advise above. I get best results at around 422*-426* finish temp(fruitiness is there). Depending on the batch size you are
roasting, you may want to drop down your charge temp. I use a 10k propane roaster, and leave air flow damper closed until I get
to turn temp(then depending on batch size), I will open full or to 3/4 open. You may want to try to extend your roast time to at least
14-15 min. I think 12 min. is a quick roast. I like the 3min. window from 1st crack to finish(dump).

 

[delimacoffee]

Once you go beyond a 40 color (Agtron) that acidity begins to fade and starts to turn more caramel (burnt sugars). Higher than expected acidity may be caused by an extremely green bean. We get beans in sometimes that don't seem mature enough that give us very high ph readings.