Measure out 1/2 cup green coffee beans and pour into the popper where you would normally pour the popcorn kernels.
Turn on the air popper. Place the bowl in front of the machine where the popped popcorn would exit, to catch the chaff. Watch the beans swirling around in the machine. They are not going to pop out the way popcorn would.In a few minutes, as the machine heats up, you’ll see the beans turning brown. Next, you’ll hear the beans starting to making a cracking sound. At the first crack, you will have reached City Roast, which is a light roast.The longer you let the beans roast from this point on, the darker the roast you will achieve. You will hear the beans pop like popcorn for several seconds. Then the sound will taper off.The next stage is when the beans start to sound more like Rice Krispies crackling in milk. This is called the “second crack” and signals that you have reached what is called a Full City” or dark roast. While the beans are roasting you'll see chaff flying off either into the bowl or box or into the air. This is normal and another reason you want to roast outdoors.
The minute you have reached your desired roast, turn off the air popper very quickly and pour the beans out of the popper into one of the colanders. Careful! The beans and the popper will be very hot. At this point, you just cool them quickly or they will continue to roast.
To cool the beans fast, you can pour them into one colander, shake them around, and then pour them into a second colander. Continue to toss the beans back and forth from one colander to the other until the beans are just warm to the touch.
Place the beans in a container that has a tight-fitting lid. However, do not apply the lid at this time. Freshly roasted beans must be allowed to “de-gas” for at least two hours, up to overnight, to achieve their full coffee flavor. If you were to grind and brew beans immediately upon roasting, you would be very disappointed. The beans are not ready to be ground and brewed until they have rested for at least a few hours, to allow them to de-gas and develop to their peak of flavor.