We Went Through More Than 5 Pounds of Beans Testing At-Home Coffee Roasters
In my decade as a coffee educator, I regularly gave tours of the roasting floor so folks could see coffee turn from green to yellow to brown. Each machine was about as big as a car, could roast 200 pounds of coffee in 10 minutes, and had specialized probes that tracked the ambient temperature inside the drum and the surface temperature of the coffee. The roaster could then monitor the roasting progress and make minute adjustments to the flame. I was convinced that coffee roasting was best left to the pros.
However, for this review, I mustered up the courage to try roasting at home. For guidance, I reached out to Chris Kornman, the roaster I used to give tours with and now Director of Education at The Crown: Royal Coffee Lab & Tasting Room. But even with all his professional experience, he wanted to introduce me to a customer of his, Dave Borton. An avid home roaster for 18 years, Borton assured me that anyone could roast coffee at home and started off with some sage words: “Be patient. Use this as an opportunity to have fun, to learn, to expand your experience in food.” He also told me to make sure I had a fire extinguisher handy, just in case. Armed with those two tips (and plenty more technical advice), I selected eight home coffee roasting machines and set out to find which ones roasted the best coffee and were the easiest to use and clean.
The Winners, at a Glance
This air roaster was easy to set up, had customizable settings for fan speed, heat, and time, and roasted great coffee. Its settings were easy to tweak for better-tasting brews, and its catcher kept counters clean from papery silverskin chaff, while its glass roasting chamber was easy to clean.
Modeled after classic popcorn makers, Popper has settings for time and temperature so you can make easy adjustments based on your flavor preferences. I also really liked its automatic cooling cycle, which meant you didn’t have to babysit your coffee.
If you’re looking for a straightforward air roaster, the JAVASTARR only has three buttons: medium, dark, and cool down. It roasted coffee well, and I liked that the fans rotated the coffee from the sides rather than from underneath.
The Tests
- Roast Tests: I roasted two batches of coffee with each machine—one following the manufacturer’s instructions and the second with slight tweaks based on time, temperature, and color to improve the flavor profile. I also took note of different settings, how easy they were to adjust, and how long each machine took to roast a full batch.
- Taste Tests: I tasted each roast side-by-side to compare flavor quality between each batch and between each roaster. I evaluated each coffee for tasting notes, sweetness, balance, acidity, and aftertaste. I also took notes on how the adjustment to the second roast with each machine showed in the coffee’s flavor profile compared to the first.
- Usability and Cleanup Tests: I evaluated how simple each roaster was to set up, how easy it was to load in green coffee, and how straightforward each was to operate. I also looked at the different settings on each roaster and how clear they were to adjust, as well as how easy each roaster was to clean.
What We Learned
Why Roast Your Own Coffee?
With so many great coffee companies out there, roasting your own at home might feel unnecessary. At the same time, home roasting lets you pick from a much wider selection of green coffee options (through sellers like Sweet Maria’s or Royal Coffee) than any one coffee company can ever offer roasted. You can also dial in the roast profile that matches your exact flavor preferences. And while buying green coffee is around half the cost of buying roasted coffee, roasting your own takes a dedicated amount of time and effort. That is to say, it’s a better hobby for an aficionado than it is a cost-cutting measure—but if you’re ready to take the dive, it lets you fully customize your morning coffee experience.
The Basics of Roasting Coffee
When we brew coffee, we’re using the roasted seed of the coffee cherry, which grows best at high elevations around the equator. The flavor of a particular coffee comes from a variety of factors on the farm, how the seed was processed from the cherry and dried, and how the roasting process develops sweetness and complexity. Green coffee is full of starch and, as you apply heat, that starch breaks down into sugars that then begin to caramelize. “You’ll want to listen for the first crack,” Kornman says. “That’s when the last bit of moisture finally evaporates and the coffee pops open, kind of like popcorn.” The first crack, he explains, signifies the moment coffee begins to rapidly caramelize. Keep roasting, and coffee will experience a second crack when the caramelizing sugars begin to burn (which is where you get dark roasts). While professional roasters have access to high-end temperature probes and roast tracking software, Kornman’s best advice was to listen for the first crack and aim for about two more minutes of roasting. After that, the best way to tweak your settings would be to taste the coffee and then change the roast time or temperature to try to hit the flavor profile you’re looking for.
The Two Main Types of Roasters
There are two main types of roasters for home and professional settings: air and drum roasters. Air roasters, like the Fresh Roast, Popper, and JAVASTARR, use a high-powered heating element and fan just like air poppers for popcorn; they roast coffee purely through convection. Drum roasters, on the other hand, feature a horizontal rotating drum with a direct heat source applied to the outside. The Dyvee Coffee Roaster was the only drum roaster I tested, as most drum roasters for home are quite expensive. Most coffee roasting companies use large drum roasters and the roasting process comes from direct conductive heat from the drum itself as well as convective heat from the coffee being tossed into the air by the rotating drum.
Roasting Good Coffee Takes Practice
It took over 15 roasts before Borton was happy with his results. “Coffee roasting is both art and science. Learning never ends with coffee and that makes it fun,” Borton says. “You are going to drill through the same coffee, roasting it time and time again, to learn your roaster and begin to learn coffee.”
Tasting (and Tinkering) Were Key to Better Results
Both Kornman and Borton were clear on one thing: The only way to understand your roast profiles is to taste your results every time you make an adjustment and note how it affected the flavor. Along with cupping my roasts (a standardized way of tasting coffee), I also brewed pourovers of my top coffees to see how the results changed between brew methods. Though I never ended up with perfect results, it was clear that the Fresh Roast and Popper machines were the easiest to adjust, and I also saw the biggest improvement in flavor between the first and second roast on each. Even though I had decent results from using the Presto Poplite Air Popper, its lack of settings made it easy to rule out. I was surprised at how drinkable the coffee from the Nuvo Eco Ceramic Handy Coffee Bean Roaster was, but having to manually rotate the coffee over an open flame meant there was a lack of repeatability in the process (plus my arms were tired).
Air Roasters Were More Practical (and Tidier)
Not only did the best-tasting results come from air roasters, they were also faster, generated less smoke, roasted more evenly, and were easier to set up and clean—all I had to do was wipe them out with a damp cloth, and they all had filters that caught chaff and kept my counters clean. While most of my air roasts only took around seven minutes, the Dyvee took over 25 minutes to complete a batch, and the Nuvo Eco required 12 to 15 minutes of hand-tossing the coffee to make sure it didn’t burn. I wasn’t even able to finish roasting batches with the JIAWUNSHUNN Electric Coffee Roaster and Great Northern Stainless Steel Stovetop Popcorn Maker. Both scorched the coffee due to direct heat and poor coffee circulation and generated so much smoke that I had to cut the roasting process short.
Don’t Forget Proper Ventilation
Roasting coffee will always generate some amount of smoke, so be sure that you have proper ventilation set up over your roaster. This could be an overhead vent hood, open windows with a fan blowing, or even roasting in a garage with the door open. I thankfully never set off a fire alarm during my testing, but if you’re going to roast at home, be sure to follow all safety precautions.
The Criteria: What to Look for in a Home Coffee Roaster
The best home coffee roasters are easy to set up, have multiple settings to control the roast profile, and are also easy to clean. They are also able to roast coffee evenly and quickly and improve the flavor of the coffee when adjustments are made.
The Best Home Coffee Roasters
What we liked: The Fresh Roast SR540 comes in three parts: a base that houses the fan and heating element (along with the control panel), a glass roasting chamber, and a lid that has a mesh basket designed to catch any chaff that flakes off of the coffee during roasting. It has three control options: fan speed, power, and time, which gave me the most control over the roast cycle than any other machine I tested. The suggested settings produced a coffee that was sweet, with some caramel and milk chocolate notes, and that had a clean finish. For the second roast, I increased the fan speed, lowered the power setting, and prolonged the roast. That cup showed more brightness and flavor clarity, with light fruit notes to balance out the body and sweetness that still came through similar to the first roast. I also really liked that at any time during the roasting process you could kill the roast and start a cooldown cycle by pressing the Run/Cool button—that way if a coffee is getting darker than you’d like it to, you can catch it before the roast starts to scorch. Otherwise, the cooling cycle will start automatically when the timer runs down. The detachable glass roasting chamber was also really easy to clean, too—just wipe with a damp cloth or wash with warm soapy water if the coffee oils start to build up.
What we didn’t like: The fan is narrower than other air roasters I tested, so during the early part of the roasting cycle when the coffee was heavier, it didn’t rotate thoroughly and some coffee roasted unevenly. However, once the coffee hit the first crack and started browning, all the coffee seemed to catch up, and there were no traces of unevenly roasted coffee in the taste tests.
Price at time of publish: $209.
Key Specs
- Materials: Plastic, glass
- Weight: 5.64 pounds
- Dimensions: 14.1 x 8.5 x 8.4 inches
- Capacity: 114 grams
- Settings: Fan speed, power, time
- Care instructions: Wipe clean with a damp cloth
What we liked: Popper was designed after classic air popcorn poppers, only with a touch more control. It has two fan speeds (though they recommend you only use high), a continuous dial for the heat level, and a programmable timer. Instead of a chute, Popper has a cage to catch the chaff (though a fair amount still snuck through). But the thing I really loved about it was the automatic cooling cycle. When I started a batch with Popper, I added the coffee, set the heat dial, and then set a time—but no matter what time I set, the last three minutes were a built-in cooling cycle. That meant I didn’t have to babysit the roaster towards the end of the cycle or worry about the coffee scorching. The recommended settings from the manufacturer roasted a coffee that was sweet, and had some red apple and milk chocolate flavors, but tasted toasty in the finish. For the second roast, I shortened the overall roast time and increased the heat slightly, which brought out more fruit qualities and a distinct sweetness (though there was still a hint of smokiness). The roast chamber was easy to wipe out with a cloth (once it cooled) and, overall, I think it offers great roasting capabilities at a reasonable price.
What we didn’t like: I wished that the roaster had more fan speed settings, especially since the low setting isn’t recommended for use while roasting since it’s not powerful enough to fully rotate the coffee. The chaff catcher also let a fair amount of chaff through, and I had to wipe down my counters afterward.
Price at time of publish: $79.
Key Specs
- Materials: Plastic
- Weight: 4.2 pounds
- Dimensions: 7.5 x 7.5 x 15.5 inches
- Capacity: 90 grams
- Settings: Fan speed, heat, time
- Care instructions: Wipe clean with a damp cloth
What we liked: With only three buttons, the JAVASTARR was a straightforward air roaster. I liked that the roasting chamber fans were horizontal so that the coffee spun in a circle instead of being rotated up and around by a vertical fan. The medium and dark settings seemed to change the temperature slightly while roasting. When the first batch roasted on a medium setting tasted a little sour and underdeveloped, I tried the dark setting. I monitored the roast time and color, and the second batch had some fruitier flavors balanced with chocolate and caramel notes but was still a little bitter and dry on the finish. If you’re curious about roasting coffee at home and want a very simple machine to try it out, the JAVASTARR is a good option, as the only variable you’ll need to track is the time of the roast.
What we didn’t like: There’s no countdown timer so you’ll have to watch each batch carefully during roasting. I also wish it was a little more powerful so it could roast batches in a shorter timeframe, which would give the user slightly more control over the flavor development.
Price at time of publish: $100.
Key Specs
- Materials: Plastic
- Weight: 3.3 pounds
- Dimensions: 6.89 x 8.27 x 9.25 inches
- Capacity: 100 grams
- Settings: Medium or dark
- Care instructions: Wipe clean with a damp cloth
The Competition
- Dyvee Coffee Roaster: Setting a rotating electric glass drum over a gas burner felt precarious. Ultimately it was too big to efficiently roast a batch of coffee without a high-powered, standalone burner, with batches taking over 20 minutes and the resulting coffee tasting flat.
- Nuvo Eco Ceramic Handy Coffee Bean Roaster: This roaster required the user to rotate the coffee over an open flame by hand, which was tiring for its 12- to 15-minute roast cycles. The coffee from this roaster was tipped, meaning the edges of the beans were scorched and added bitterness.
- JIAWUNSHUNN Electric Coffee Roaster: A cross between a crock pot and stirrer arm popcorn maker, this machine roasted extremely uneven coffee that tasted like vinegar and smoke.
- Great Northern Stainless Steel Stovetop Popcorn Maker: Though stovetop popcorn makers can be used to roast coffee, the stirring arm passes over the coffee instead of evenly rotating it. It also created a lot of smoke compared to air roasters.
- Presto Poplite Air Popper: Without any control over the settings, coffee roasted unevenly in this air popper, though the end results were passable in taste tests. It also had a fan that was so powerful, it blew unroasted coffee out of the chute onto the counter.
FAQs
Is it cheaper to roast coffee at home?
Roasting your own coffee at home can be cheaper, but it also requires a lot of time, care, and effort to get the results you want. Heavy coffee drinkers might appreciate buying green coffee in bulk for a fraction of the cost of roasted coffee but fine-tuning a roast profile to match the quality of your favorite coffee roasting company can take a long time to perfect. We think it’s best for enthusiasts rather than people looking for a cost-saving measure.
How easy is it to roast your own coffee?
Roasting coffee at home can be easy—our two favorite home roasters use a set-it-and-forget-it timer with customizable fan speeds and heat settings. We had relatively good results with the manufacturer-suggested settings out of the box, though tweaking roast profiles to bring out the flavors you’re looking for can take some time and experimentation to perfect.
What is the best way to roast coffee at home?
While there are a variety of different coffee roaster styles that we tested, the most consistent and easiest to tweak were air roasters. These machines use a high-powered fan and heater to roast coffee, and our top three picks had settings to adjust fan speed, heat, and time, allowing you to easily tweak roast profiles to bring out different flavors. They also tend to be less expensive than drum roasters, which feature a heat source (like a gas burner) applied to a rotating drum and require more practice and coffee roasting knowledge to get good results.
Why We’re the Experts
- Jesse Raub is Serious Eats’ commerce writer and spent over 15 years working in the specialty coffee industry. He’s our in-house coffee expert and regularly tests coffee gear for this site, including reviews of espresso machines, drip coffee makers, and moka pots.
- He tested eight roasting machines and went through more than five pounds of green coffee over 30 batches of roasting.
- For this review, Jesse interviewed Chris Kornman, the Director of Education at The Crown: Royal Coffee Lab & Tasting Room, as well as Dave Borton, an avid home roaster with over 18 years of experience.