How to Roast Green Coffee Beans in a Popcorn Popper
After about 3 minutes you should see some husks coming off into the bowl. If you like a light roast, a 5 or 10 minutes should give you a fairly good roast. Pour the beans in to a bowl or colander and shake them around for a while to remove additional coffee bean chaff and help cool them off. Let them cool for 24 hours prior to grinding and making coffee.
I like a dark roast, but in my experience, a popcorn popper alone does not give me a dark enough roast even when I leave the beans in the popper for an inordinate amount of time. Another option is to follow up the popcorn popper roasting with some stove top pan roasting. 
After you remove the beans from the popper and get rid of extraneous husks, place the beans in a frying pan and pan roast the beans over high heat, keeping the lid on most of the time. Shake them around often. You can optionally spray a mist of water on them to prevent them from drying out too much. Pan roast them until they are nice and dark. Then let them cool for 24 hours and enjoy.
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