A couple of things to begin with…
Make sure that your kitchen is well ventilated. The last thing that you want is to set off your smoke detector, or worse, your fire suppression system!
Keep odor in mind. When you begin roasting green coffee beans, they will emit a grassy smell that will begin to smoke and develop into the familiar coffee-like odor. This odor can be a bit much, cloying, in fact, and you should decide before you begin to roast your own coffee if you can live with the smell, as it is intense and will linger. And linger. And linger. I actually roast my coffee out on my back deck. Just so you know!
The length of your roast will depend on the color of the beans. The darker the bean, the fuller body the resulting cup of coffee will be. Here’s the rainbow:
- Light brown – Under roasted. The coffee may be sour.#Light medium brown – Full body, slightly sweet.
- Medium brown – Full body, strong aroma, slightly sweet.
- Medium dark brown – AKA Light French or Viennese roast. This has full body, strong aroma, and is sweet.
- Dark brown – AKA espresso or French roast. This has a full body and is sweet.
- Very dark brown – AKA Spanish roast. This has a weak body, mild aroma, and is not very sweet.
Listen for the cracking sound. When coffee begins to roast, the water inside the beans begins to evaporate, causing a cracking sound. This is called “first crack.” Once the coffee rises further in temperature, there is a second crack.
Once your beans are roasted, you will want to use them fairly quickly, as coffee goes stale in short order. It’s best to roast your own beans in small batches. It’s also best to store them in an airtight canister. (Link to Amazon canister here)
The oven method
You will need a perforated sheet pan with a lip (link to Amazon here) to roast coffee in your oven.
- Preheat the oven to 450F.
- Pour the green beans onto a perforated sheet pan with a lip. Make sure that the beans are in a single even layer.
- Place the pan in the oven on the middle rack.
- Roast the beans for 15 to 20 minutes, stirring the pan every couple of minutes to help them roast evenly.
- Watch them carefully, as the difference between perfectly roasted and burned can be as little as a few seconds.
- Remove the beans from the oven when they reach the desired color.
- Pour them into a colander and stir them around. This will cool off the beans and keep them from over roasting. This will also help remove the chaff.
The air fryer method
The air fryer method produces a very even roast, due to the convection technology they employ. (Link to air fryer on Amazon) Most hot air roasters come with instructions on how to roast coffee. The basics are:
- Heat the appliance to 450F
- Place green coffee beans in the basket in a single layer
- Roast for 15 to 20 minutes, keeping a close eye on the color of the beans.
- Remove them from the roaster and pour into a colander and stir to cool down.
The stovetop method
This method calls for an old fashioned stovetop popcorn popper (with a crank handle). (Link to Amazon here) This method works well, but you cannot stop cranking, so know that you will be tethered to your stove for 15 minutes or so. You can also use a cast iron pan, but this method is prone to burn. And you have to keep stirring. Also be aware that the beans can burn more easily with this method than the oven or air fryer method.
- Preheat the corn popper on the stove, to medium heat. We’re looking for a temperature of about 450F.
- Add no more than 8 ounces of green coffee beans at a time.
- Close the lid and start cranking. Don’t stop cranking.
- Listen carefully for the “first crack.” This should take between 4 and 7 minutes.
- Make sure that your range hood fan is on high. It might also help to open a window.
- Once you hear the first crack, begin checking the beans after 1 minute. Keep a close eye on them until they reach the color you want.
- Pour into a colander and stir the beans to cool them off.
Now that you’ve know how to roast coffee beans, it’s time to grind them up and make a truly homemade cup of coffee!