Roast Profiles, II

Yesterday I wrote down some largely incomprehensible thoughts about roast profiles I have been using. Let's see if today I can make things a bit clearer.

There is another popular option for roast profiles, which more or less says "crank the heat as high as it can go (482 degrees) until first crack, and then lower it until the end of roast". This is not a profile to use until you are fairly familiar with the Gene Cafe, since you can easily make charcoal (or a fire) if you are not tuned in to the sounds and smells of the roast, and it can be tricky to get things to slow down such that there is enough time between first and second crack for sufficient flavor development. This fast ramp can also reduce the amount of perceived body in the coffee.

However, this can be an effective method for high-altitude/dense seeds. Using this method tends to preserve a lot of acidity in the coffee, which can be good or bad depending on the coffee itself and what you are looking to accomplish. You can further combine this with my observations from yesterday on starting temperature to come up with some sophisticated profiles that can really dial a coffee in.

Let's look at some examples, and I'll refer back to previous blog postings.

#1 High-altitude, bright, Central American coffee. Here I'll refer back to the Guatemala Yellow Bourbon posting. Here I was looking for a light roast, and to ensure that the acidity wasn't too overpowering. Therefore I started at a somewhat higher temperature (350 degrees), and crept up on first through some intermediate temperature ramping.

#2 Low-altitude, low-acidity coffee. An example might be an Indian coffee. Since this is lower grown, I try and keep the temperatures more moderate, and again use some intermediate temperatures in the ramp to slowly develop the flavors.

#3 High-Altitude, medium acidity coffee. An example might be a Yemeni coffee.
Here I was looking to add some sparkle to the coffee, since Yemen can be a bit brooding, so I used a fast ramp up to first crack and then settled things down. I would use similar profiles for a Kenya coffee, where you can be aggressive with the heat due to the extreme seed density.

So there you have it. Depending on what you are looking for out of the coffee, you can choose how fast you move it along to change the amount of acidity in the coffee, and trade that off against body, etc. There are a lot of variables to play around with, and I'll try to highlight my thinking as I roast, taste, and post about these coffees.