Prior to leaving for the SCAA conference in Seattle this year, things were really hectic in the roasting area. New coffees were coming in and I was working to transition to new lots of several coffees. This involves roasting small batches of each coffee, pulling several samples of each, tasting each sample, repeating that process if necessary with adjustments until a sample is found that tastes right, roasting a test batch to check that I really do have the right profile, and if that coffee was used in a blend that blend must be checked and possibly adjusted. Most of the effort focused on the new Yemen Mocha Sanani, Rwanda A, and to a limited extent the next lot of Brazil Mogiana. These were worked out without much difficulty, though I still need to work on some of the blends to get them to use the new Brazil. I spent a lot of time working on one other coffee: Kenya AA.
I'm a big fan of fine East African coffees in general and good Kenyan coffees specifically. I really love the intense, vibrant acidity and sparkling clean taste of a top quality Kenyan. The latest lot was disturbing. I was able to make it taste slightly sweet and extremely mild, sharp and intensely sour, or dull. That is not how I want my Kenyan coffee to taste, but after five test batches and thirty-seven distinct samples, those seemed my only options. If I could tone down the sour sample and bring in some sweetness, I would have what I wanted, but I couldn't figure out how to do that. I went to the conference without having a Kenya profile I could be happy with.
At the conference I tried to learn as much as I could, so I took some of the more interesting sounding skill building workshops. One was Organic Acids & the Chemistry of Coffee. This was largely a lecture on some of the acids found in coffee and how the amount of these change during a roast with a tasting that involved trying a coffee and trying that same coffee a few more times, each with a different acid added. I found it interesting and would recommend it to other roasters, but what really got my attention was the sample with acetic acid added. I didn't like it, but more importantly, I recognized the taste as something I didn't like in the latest lot of Kenya AA. If I could, through some trick of the roast, reduce that without going too dark, I thought I might have something. In my head, I started to work out a possible roast profile. I needed to roast the coffee darker, but not too dark, and the roast needed to be fast to prevent the destruction of chemicals I wanted to keep. The resulting profile is odd, but haviing tasted it today, it is clearly the correct way to roast this lot.