All roasts coming out bitter?


I just roasted 5 different profiles on a wet processed Ethiopian and every single one came out very bitter. I am posting this as a “live update” my thoughts and how I am going to move foward. And if people have a similar experience. I’d hope this is a thread where we can share those experiences.

So there have been problems with the update recently. But I am not sure that can be the source of this problem. What I think is the most likely source is the drastic weather change, it is 20F cooler and 20% less humid. (80F,80RH vs 60F,60RH). In order to test this. I’m going to re-roast the same profiles (it’s still as cold, actually a little bit colder 53-60F, with a batch sizes of 45g instead of 55g. And then I’ll roast a 3rd set with a flat fan setting of 80%. 4th set with 76% flat fan and a 5th set where I turn of the “time calibration” setting, using the orignal profles where I used a higher fan 84-84 to compensate.

The reason I am not going to change the profiles, is becasue I arrogantly have full confidence in them. And this test will cost me most of my 5lb bag of washed Ethiopian. But again they are coming out super bitter…maybe it’s the bean, I’ll also be testing other beans and contribute those results later.


The average roasting ambient temperature in the UK is cool and rarely humid and have never had a problem with the Marshall Etheo.

I wonder if it is the beans? Interested to find out what you discover


Are you getting super distinct fruit, because on a good day/roast for me the profiles would give me such clear tastes. I just want to make sure because when the temp drops here I always have problems with the roast.

After doing a little bit of everything and not using up like 4lbs, I feel more comfortable but not 100% in saying that it is the weather again. Mostly because my temperature marks on my makeshift thermometer are coming in slower, 1C is coming later. But I think the bitter is coming from the bean itself. I did the Sum Man 5.17142 (I know I should name my profiles better, working on it) on a Guatemalan and it seemed a little light and was just shy of 2nd crack when I was expecting it happen.


I find the Marshall Etheo needs a general raising of the profile for my cooler less humid conditions. I run it at +5C ( all points) from the original one you posted.

I always get the fruit notes from naturals from it, which is why I always try it as well as a few other profiles I like to run with naturals. I can’t remember a single failure from it in terms of flavour.

A couple of beans (especially an Ethiopian Guji) were maybe denser than normal ( we don’t get density info on beans in UK or at least I never have) so it struggled to reach 1C. These were slightly underdeveloped but the fruit was certainly there and still pleasant to drink. The body a bit “bready”

Do you think that the current fan issue could be a factor?


Raising the points by 5* is a very good point. I can’t believe I didn’t remember that before.

I thought it could be the fan but as I taste and roast more (I thankfully don’t have the cooling fan problem, I think) it seems a weather issue. The weather was a lot warmer last night when I did another round and the beans started tasting closer to what I was expecting not the blooming of fruit as I expect in warmer weather . These are also wet processed beans so I’m not expecting them to taste like DP. But I’ve used these profiles on another Ethiopian WP and was trying to gain a familiarity since so many variables were changing at once.

Density is easy to measure and one you can do at home. Take a shot glass and fill it up with bean and weigh the beans. Then compare that bean weight to other beans. You can find the actual density by measuring the volume of that glass and divide bean weight by glass volume. The volume can be found by filling the glass full of water and then weighing it. 1 mL of water = 1mg of water.


I did try the relative density measurements a while back on Bourbon from various origins and didn’t find much difference. It didn’t help me with the roasting. African Bourbon and Central American don’t like the same profile even if the density is similar. So I stopped doing it. More out of laziness.

Is it a washed Yirg that you are roasting? The washed Ethiopian’s I’ve tried tend to be much more subtle in the fruit department but you can get interesting florals and tea notes.

I’ve just finished a batch of Kochere G1 which was much nicer (imo) than the Ikawa greens we got with the roaster. They did really well on the Kochere Debo profile. Peach, lavender, bergamot.

I find washed coffees from Burundi and Kenya to be hugely fruity - often more so than naturals.

I was away for a few days past and tried filter coffee in a couple of cafes - one an Ethiopian natural the other a Kenyan. While they were both decent, the roasts had really muted the coffee of their vibrancy. Probably a commercial decision.


That’s an interesting find about the density. This is the coffee I’m roasting, it wants to be chocolate

Drinking a couple of the roasts, I am findings that the acidity didn’t get developed enough and still retains that raw Ethiopian flavor, drinking the In Search of Sunrise 3 it was like eating those chocolates filled with liquor. The chocolate was a rich milkchoclate with cherry and the liquor was the Ethiopian juice. The Hassan U3 is super deep rich caramel. I really want to find those peaches and apricots though. I think I’ll raise the profiles by a couple degrees and do another round. I have some family in town for the weekend so it might not happen until Monday. But it’s seems the bitterness has diminished, hopefully.

Personally I always blame the roaster (the person lol). Because I’ve roasted coffee where no matter what, I just couldn’t mess it up by brewing. And so when I go to a shop it’s out of desperation and I expect nothing. Usually when I travel now I just bring some tea and buy a cup of hot water. And believe you me, the water can be bad too. :man_shrugging:


Well that sounds like a great coffee. I can’t recall tasting an Ethiopian like that at all. Multi dimensional.

What great info you get from Sweet Maria’s. Over here HasBean are the only one that comes anywhere near providing decent info.