I just found out this week that you can roast coffee beans in an air popper. An AIR POPPER!! Apparently people have been doing this for a while. I discovered this while I was shopping online for a home coffee roaster, and came across the air popper method by accident. I don’t need much convincing to make stuff just for the sake of making stuff (like bread, tonic water, and ice cream – just because they taste a whole lot better when home-made, despite, or maybe because of, the many hours they take to prepare and source the ingredients). Needless to say, I immediately dragged out my trusty old popper and threw in some green coffee that I got at my local homesteaders shop. Within 8 minutes the coffee was roasted to perfection, and the next morning Mark made the best cup of coffee to ever come out of our kitchen. I had made a nice medium roast, which as I understand, means a higher caffeine level. Which is great for parents of a teething 4 1/2 month old and owners of an ancient kitty (whose favourite time to demand cuddles by purring loudly like a gas-powered lawnmower in our ears or by pacing all over the bed, is 3-5 am) who are not always getting adequate sleep levels, and just really love a good coffee.
Home-roasted coffee is cheaper (the coffee we get is about $15/pound, and the green beans I got were $7.50/pound – bearing in mind that for each pound of green beans you’ll get about .85 pounds roasted coffee), tastes amaaaaazing, and is dead-easy. Thing is, it doesn’t stay fresh very long, so best is to make small batches often. Green coffee beans have a much longer shelf life than roasted coffee. Plus it’s pretty cool to be roasting your own coffee. It’s up there with making gin and spinning yarn.
Before I start, you should know that using your air popper in this method will likely void the warranty. There is also a risk that the beans and the machine will catch fire, or at the very least, send lots of smoke all over your kitchen. This risk is extremely small if you don’t leave the machine unattended while it’s on (in other words, do not attempt this if you are very drunk, tired, or distracted). You will probably also melt the plastic lid, and you may burn out the motor or the elements faster than if it were just used for popcorn. That said, you can find pretty cheap second hand air poppers at yard sales or thrift stores.
The type of air popper you use is important, it has to be the style with the vents around the base, so that the chaff will get properly blown out of the chamber and not catch fire. Also, some machines have an overheating shut-off feature, which means you might have to roast in shifts. Not sure how well this method works though. Mine is a Toastess that I got at a yard sale for $5 about 8 years ago, and it did a great job, all in one go. Position the vent either over a sink or large bowl so that the chaff can blow out. It will end up all over your kitchen anyway, but most of it will be somewhat contained. Did I mention this is a messy process? You may want to set up near a kitchen fan, because the smell can get a bit intense and will get all over your house. This is not necessarily a bad thing, but it does make it harder to wait for the coffee to be ready before jumping in.
The first time I roasted coffee, the grate on the plastic lid started to melt a little, so I MacGyvered a protective cover out of tin foil that I wrapped around the vent, and poked holes through. That seems to have done the trick. Doesn’t look too pretty, but the air popper isn’t that sexy either.
Next, turn on the popper for about a minute to get it nice and hot. Meanwhile, measure out the coffee. Each machine is different, so good idea to check your manual, but general rule of thumb is to make sure the beans are deep enough to cover the vents (this will help hold the heat in more efficiently, which means your beans will roast more evenly). It’s a good idea to weigh them as well, so you can fine-tune and predict the results for next time. I used 75 grams.
With the machine running, remove the lid, dump your beans into the machine and put the lid back in place. The beans should be moving in the chamber, but not too fast. If they aren’t completely covering the vents, add more beans. Start a stopwatch, that way you can tweak your results and make the perfect roast every time.
After about a minute or two, lift the butter cup (carefully, because the chaff will be blowing up by now and all over your kitchen, despite your best efforts to contain them) and stir the beans with a chopstick or the handle of a long wooden spoon (which will send more chaff flying. Don’t worry, just vacuum later). Put the lid back in place and watch as the beans change colour. I like to stir the beans a few times during the process if I’m noticing the beans are not roasting evenly.
After about 3-4 minutes, you’ll hear the beans pop a bit like popcorn. This is called the first crack (no Rob Ford jokes please). If you like a very light roast you can stop roasting now.
The longer you go the darker it will get. Keep checking in the chamber to be sure you haven’t gone too far (if the beans look black and smell burnt, you’ve gone too far. Dump out the beans and start again. Unless you like burnt coffee, which I guess might work for some types of beans.) It may start to smoke a bit (at first it’s just water vapour escaping from the beans), but as long as it’s not foul-smelling smoke, you’re doing good. I roasted mine 7 minutes 45 seconds (yes, you have to time it down to the second) and stopped it just as it started to pop again (this is called the second crack). Each machine is different, so you’ll have to rely on trial and error to come up with the perfect formula. Having multiple appliances plugged in to the same outlet can even make a difference in the timing, because the popper won’t get as hot, and might not be able to get hot enough to create a dark roast. If you’re eyeballing it, make sure to stop the machine just before it looks ready because the beans will keep cooking for about a minute or so. As soon as you stop the machine, take off the lid (with oven mitts – it will be hot enough to melt the plastic!) and quickly pour the beans into a sieve and swirl it around to get air on the beans, or pass them back and forth from the sieve to a bowl. The idea is to get lots of air on to the beans to cool them quickly and stop them cooking.
When they’re cooled, put them in a jar and let them sit for 24 hours to let the CO2 dissipate and the flavours to develop. It will be good right away, but will be even better if you can wait one day, or up to five days.
Keep track of the different timing you’ve tested on different beans, so that you will be able to create perfect batches every time. And you will impress all your friends when you show up for brunch with a batch of the best fresh-roasted coffee. No one will believe that it came out of your popcorn machine.