Roasting coffee is fun, enjoyable, and surprisingly easy. You might not achieve the “perfect” roast on your first try, but you should be able to consistently roast a drinkable coffee with some practice. All you need are some basic supplies, green coffee and a little knowledge.
You Can Use a Variety of Equipment to Roast Coffee
Home roasters are ingenious people and have used a wide variety of equipment to roast coffee. If you search home roasting forums, you’ll find people using the following items:
- pans on stovetops
- cookie sheets in ovens
- toaster ovens
- old air popcorn poppers
- home coffee roasters
For several reasons, we recommend starting out with an old air popcorn popper, which was what we roasted our first batches of coffee on.
First, you should at least start out roasting outdoors. A lot of smoke is produced, especially if you burn the beans, and you probably don’t want that smoke in your home. (Your family or housemates certainly don’t!) For this reason, using a pan on a stove or a cookie sheet in an oven isn’t the ideal way to try roasting coffee. Once you’re familiar with the process and know how much smoke is produced, you can roast coffee in your kitchen if you’d like. Until then, though, we suggest staying outside, or at least in your garage.
Second, old air popcorn poppers are affordable. Older models from the 1960s are better than newer ones, so the best place to find one is on Ebay. Prices change constantly, but there are usually affordable models for sale. You may want to upgrade to a home coffee roaster eventually, but there’s no reason to spend hundreds of dollars on one until you know you want to pursue home roasting. When first starting out, an old popcorn maker will work fine. Additionally, when you graduate to a coffee roaster, you can have the pleasure of passing it on to someone else who’s curious about home roasting.
Third, toaster ovens are also portable and inexpensive. Many toaster ovens, however, don’t get hot enough for coffee roasting. During roasting, beans can reach 400°F and even higher temperatures. Many toaster ovens have a maximum temperature of only 400, 425 or 450°F. These aren’t the temperatures that your coffee beans will reach, though. Depending on the ambient temperature, there may be a 20- to 50-degree difference between your toaster oven’s setting and the temperature of the beans. Thus, a toaster oven that has a maximum setting of 450°F will barely be hot enough to reach a light to medium roast. A popcorn popper, however, can get the beans much hotter because it operates at a high temperature, and it keeps the beans closer to the heat source.
Sweet Maria’s and Local Roasters Have Green Beans
There are two main places to go for green coffee beans. Most home roasters who purchase their green beans online get them from Sweet Maria’s, which also has a wealth of resources on home roasting. If you’d rather purchase green beans in person, look up a local roaster near you. Few roasters advertise green beans, because there’s not much of a market for them. Most roasters will gladly sell you a pound or two, though, and they’ll relish the opportunity to talk with a fellow enthusiast about roasting.
The First and Second Crack Are the Hallmarks of the Roasting Process
When roasting, your beans will go through several stages, but the two most prominent ones are the first and second crack. Because these are clear steps in the roasting process that happen at precise temperatures, roasters often base their roasts on them. For example, a roaster might take a coffee 10 second beyond the second crack (if they’re roasting an extremely dark roast).
The stages are:
- Yellowing, when the beans change from green to yellow and emit a grassy smell.
- The First Crack, which is identified by a pronounced cracking noise that sounds like popcorn popping. The sugars in the beans are beginning to caramelize, and the oils are starting to move towards the surface of the beans. The chaff will begin to become loose around this time.
- The Second Crack, which is identified by a faint cracking sound that sounds like Rice Krispies in milk and is a much more subtle sound . The smoke will become more pronounced and may appear blue.
- The Mythical Third Crack — if you reach this, you’ll be calling the fire department.
When you’re first starting out, don’t worry about aiming for a specific roast level. Simply try to get the roast somewhere between the first crack and the second crack. After you can consistently keep the roast level between these two points, you can begin to try for a specific level.
With home roasting, it’s particularly important to stop the roast a little before your desired roast level. Cool the beans off as quickly as possible, so they stop roasting. Between the time you turn your roasting device off and cool the beans to an ambient temperature, they’ll roast a bit more. Home roasters refer to this as letting the roast “coast.”
Finally, make sure to let your coffee degas before trying it. Try it 2 to 5 days after roasting.
If you’re exploring home roasting, we’d love to hear about your adventures. It’s how we got started, and now roasting coffee is our profession. Share your experiences with us in the comments, and follow us on Instagram. We post lots of pictures of roasted coffee, and matching roast levels to pictures of properly roasted coffee is a great way to learn how to roast coffee.