I started roasting some of the pounds of coffee that we consume last year after reading an article in one of my self-sufficiency magazines and then doing some further research on the web. I ended up picking up a Poppery II hot air popper at a garage sale for a couple of bucks to do my roasting. (My son tells me that the older, heavier duty models like mine were selling on e-bay for $60+ last year! He got his at a resale shop for under $10.)
My eldest son used to work for Starbucks and Caribou and has a father-in-law who invested in a home-size coffee roaster, so he had knowledge of coffee and had done some roasting. We roasted the first batch together. I had already read about the first and second crack and what the beans would look like for a light, medium, and dark roast. It still was good to have the support of someone else when doing something new.
The hot air popcorn popper is a fluid bed roaster like the big ones commercial roasters use only on a mini scale. (Mmmm—sounds like a lot of other things we do here on My Little Farm in Town.) The (1/2 cup) beans are cooked on currents of superhot (about 400°F) air inside the popper. The machine blows off the chaff (outer skin of the green bean) during the first part of the cooking time at and around “first crack”and the nibs during the second part at “second crack” (if you are going for a darker roast). The first crack sounds like popcorn popping. The second crack sounds more like Rice Crispy breakfast cereal after you put the milk on it!
We like a really dark roast, so I usually cook my beans for about 10 minutes. (You would cook them less for lighter roasts.) The beans deepen in color as they roast. A dark roast gets very brown and shinier as the oils start to emerge. The cooking beans smell like toast that is on the burned side. There will be some smoke—so roast outside or under a cooktop hood. Some people rig elaborate exhaust systems out windows or roast in or in front of their fireplaces with fans blowing the smoke in the correct direction.
Air temperature and humidity vary the roasting times. I’ve learned the hard way that a hot air popper can’t generate enough heat for a dark roast when the air temperature outside is 41°F with a wind blowing! (I had to finish that batch indoors!) Another thing I’ve learned from an expert is that is that you will want to let the machine cool a little between multiple batches so you can wipe it out with a dry paper towel or you WILL eventually have a fire!
You should let your beans “age” for at least 24 hours after roasting (if you can resist that long) because there is enzyme action that takes that long for full flavor development. Happy brewing! Begonia.