Contributing Editor: Will Johnston

Roasting Coffee Beans at Home with Air Popcorn Popper


In this article we’ll teach you how to roast coffee at home. It’s a great way to both save money and produce a coffee to your own liking. With some experimentation you can create your own ‘signature roast’. I consider myself a coffee snob and was paying $12 a pound for one of my favorite blend and roasts. Now that I’m roasting my own I’m paying $5 a pound and have a roast which is every bit as good, if not better than what I was drinking before. I also like having the ability to create a light, medium and dark roast in the save session and have each available for the mood I’m in.

Starting out you want to locate a source for green beans. It can be tricky and we recommend Sweet Maria’s out of Oakland, California. You can order a few pounds at a time, if you consume a fair amount of coffee. They have a range of bean sources to choose from and the prices are very good. Green beans can store in a dark and cool room for up to two years without any compromise in flavor or quality.

Next you’ll need an air popcorn popper. You can pick one up at a thrift store or inexpensively at a local Target. You will only be able to roast around 1/2 a cup of beans at a time, but it only takes a few minutes, so you can roast a pound in twenty minutes or so. You’ll want to place a strainer or colander at the exit of your popper, to capture chaff and beans which escape. Start your popper and pour in the beans. You will want to cover the area where the beans are roasting to ensure they don’t pop out. You’ll begin to notice the chaff loosening and floating out. The beans should be jumping and swirling as they roast. You’ll begin to notice a smell of roasting, which has a slight burning odor. Don’t worry, just let the beans continue to roast. You’ll next notice that after around two minutes the beans begin to turn yellow.

Let the beans continue to roast until you hear a cracking sound. The cracking is called the ‘first crack’ which means that the beans have achieved a palatable roast. This is a light roast and will result in coffee which is subtle in flavor and high in caffeine. The first crack took place in the first 3 minutes. You can continue to roast for a couple more minutes to achieve a medium roast or more for a dark roast.

Medium Roast

Most coffee consumers are familiar with medium or dark roasts. Lighter roasts are popular among coffee purists, but may not be to everyone’s taste. There is a ‘second crack’ which is typically when you achieve a dark roast. The second crack takes place around the fifth to sixth minute. You’ll notice if you listen for it and are trying to achieve a dark roast.

Dark Roast

When you achieve a roast which you think will work for your first trial, remove the beans and shake them in a colander. This will remove the remaining chaff. After shaking them well, you want to place them in a container which can breath and allow the beans to out gas their CO2.

The next morning your roasted beans should be ready to grind and make coffee. Be sure to continue testing your roast level. Keep in mind that different bean origins and blends will give you different and unique flavors. Enjoy!