Cold Beans
by Keith Tomlinson, Head Peace Coffee Roaster

In the winter, the green coffee beans get cold too. This last Friday Beth and I helped to unload a truck full of coffee beans. Eight countries worth of beans converge in New Jersey and then find themselves traveling overnight in the back of a truck with not much more of a cover than a burlap sack. So, how do they get warm? We roast them.

Our roaster is a Primo, and that isn't just an adjective, it is the name of the machine. There are three stages to the roasting process: the drying phase, 1st crack, and 2nd crack. The typical roast lasts between 14 and 18 minutes long.

Step by step, here is what happens. The green beans get weighed out. We roast in fifty pound batches. Fifty pounds of green coffee yields around forty pounds of roasted coffee. The weight loss can be accounted for in the chaff that we give away and the particles that we burn off with our afterburner, which runs at temperatures between 1100 and 1500 degrees. The beans are placed in a hopper and then dropped into a rotating drum at a high temperature, somewhere in the four hundred degree range. Under the drum we have heating tiles that disperse the flame and create an even heating source making the roast more uniform. The first part is the drying phase when the bean is taking on heat. The speed with which the bean is given heat helps to determine what happens during the next two phases. It is what we do during the first and second crack that assists in determining the final outcome of the coffee. They are called cracks because the bean makes an audible sound, similar to that of popcorn, as it is expanding. This is also an indication that the bean has temporarily stopped taking on heat and is now giving it off. It switches from exothermic to endothermic and then back for the second crack. Not all of our coffees even make it to the second crack. Our light and medium roasts get pulled just before, and our dark roasts get pulled just as they are getting into it. This all happens in the upper four hundred degree range. After it gets pulled from the drum, it goes into a cooling tray that is sucking air through it and circulating the coffee at the same time. The cooling process takes around five minutes.

One piece of the final product is the quality of the green bean itself, the next is the roast, and the final is how it is brewed. Throughout the whole process of roasting we take temperature and time readings and plot them as a curve matching them to what we have done before making our coffee more consistent from batch to batch. But, roasting is much more than just matching a curve. It is about craft and intuition, it is about the smell and color and sound of the bean. It is about keeping it warm, so that it may in turn warm us.

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