Now that we know the origins of coffee, how does coffee turn from a green bean into the complex brown one trapped full of flavor?

It is all in the roasting. According to National Geographic, “Coffee roasting coaxes golden flavor from a bland bean. Unroasted beans boast all of coffee’s acids, protein, and caffeine — but none of its taste. It takes heat to spark the chemical reactions that turn carbohydrates and fats into aromatic oils, burn off moisture and carbon dioxide, and alternately break down and build up acids, unlocking the characteristic coffee flavor.”

Photo taken from Jeremy Parnell

Coffee roasting is not just a complex process, but often referred to as an art. There are several key steps in the roasting process that vary based on the roast that is trying to be achieved.

Once green coffee beans and the proper equipment are acquired, the roasting process can begin. Coffee first turns yellow as it bakes, then it begins to steam as its water content dissolves. Roasting begins around the “first crack”, which is when the bean breaks down the center; sugars begin to caramelize, and bound up water escapes. After this, the roasting process can be called complete at any point depending on the roast preference. If roasting continues, sugars caramelize more, and the bean’s color becomes darker — usually considered a medium dark roast. If darker roasts than this are preferred, then the bean is taken into the “second crack” stages where it becomes a dark roast, with very dark smoky characteristics. If beans are roasted beyond this point they tend to char, loosing all of their caramelized sugar flavors.


We got in touch with Jeremy Parnell, the owner and head roaster of Hatchet Coffee, and asked him a few questions about how he accentuates certain flavors while roasting Ethiopian beans.

What sparked your interest in roasting coffee?

- I did not appreciate coffee until later in my life. I had it once as a kid and pretty much wrote it off until about three years ago. Once I dove into the coffee world, I wasn’t settled with just brewing coffee. I wanted to know everything about it. So the next step for me was roasting. I was fortunate enough to become good friends with a local roaster, bald guy. He briefly covered the roasting process. I wanted what he had, but there wasn’t much of an opportunity there for me. So me and my good buddy Jeremy Bollman started hatchet coffee. I’m definitely still a rookie when it comes to roasting coffee, but I’m doing my homework and learning as much as I can about the process.

How long have you been roasting coffee?

-I started roasting coffee about a year ago. I started off on a home popcorn popper. It was fascinating to see the process happen. Then in February of this year I stated roasting on a small sample roaster, I was on this roaster for about 7 months and then in August we upgraded to a 5K commercial roaster.What got you interested in roasting coffee?

What do you think makes Ethiopian coffee unique?

-Ethiopia being the birthplace of coffee makes it unique right out of the gate. For me, my first eye opening cup of coffee was a wash yirgacheffe from counter culture coffee. It literally blew my mind. I thought I was drinking fruit juice. Generally Ethiopia has more fruit/citrusy forward profiles, which is so different that what coffee “should” taste like.

What are the characteristics you try to pull out of Ethiopian coffee when you roast it?

-I want to bring out those inherit juiciness/fruitless/floral/ sweet characteristics. To achieve this, roasting lighter is key. Light roast is such a broad term and I hate to use it so loosely but that’s the idea at least.

How do you achieve this?

-Depend on the bean really. If it’s a washed coffee, I try to dry that bean out as quickly as possibly. I want a quick drying phase to bring out that fruit like acidity. If it’s a natural, my roast are slower and lower. The bean is not as dense therefore it does not take much to dry it out. I keep my temps much lower.

Thank you for the incredibly informative interview Jeremy! If you would like to try Hatchet Coffee, go ahead and do yourself a favor and check out the link to their website below.

http://www.hatchetcoffee.com