There are a couple ways to approach roasting coffee on your stovetop. Here’s instructions and Pros/Cons of each approach.
First let’s look at roasting coffee in a cast iron pan, a wok, or a simple pot. Then below on this page we discuss roasting in a hand-cranked stovetop popcorn popper.
Ye Olde Iron Skillet Coffee RoastingThe application of heat to green coffee seeds (beans) to create palatable material for brewing a great cup!: Coffee roasting is a chemical process induced by heat, by... Method …or a Wok, or a Pot…
Features: Fun and easy. Cheap and definitely “old school.” This is the method I used to roast Tanzanian PeaberryA peaberry is a green coffee "bean" that has a rounded form: Coffee is the dried seed from the fruit of a flowering tree - each fruit having... (they roll nicely in the pan) 10 years ago. I thought I was the only person in the world roasting at home. This is better as an experiment, or for you cowboys and mountain men out there. Cons: It’s easy to scorch the beans and produce uneven roasts. The the coffee beans need to be stirred and/or the pan shaken continuously!
Even experienced roasters should try stovetop roasting at least once. You learn a lot by having the whole roast process unfold in front of your eyes…
What You Need: Any lightweight skillet with a good tight lid, or a heavy skillet for a real aerobic workout. (You might also try a Wok and agitate with a wooden spoon. With good technique, this method can produce fine results.) Gas or Electric stove. An oven thermometer. A big spoon, a big bowl or metal colander for cooling, and oven mitts.
Instructions:
- Turn on your stove-top exhaust fan, or open a kitchen window. Have all your supplies within reach.
- Measure out about 9 ounces of coffee by weight, or 12 ounces by volume for a large skillet.
- Preheat skillet over low flame/medium electric burner setting with the lid on. An Oven thermometer placed inside can tell you when you have reached 400 degrees. Stabilize at 450.
- Remove the thermometer, toss your beans in there, and armed with oven mitts, start shaking (a…the pan). I use a wooden spoon to stir the coffee, and some people prefer a metal whisk.
- If you can cover the pan, this helps trap the heat, but then you can’t stir easily. A conundrum! However those who use a pot rather than a heavy pan might do better shaking it and keeping it covered too.
- This is the most intuitive, rough and tumble (literally) roasting method. Keep the beans in motion. Listen for the “first crack” and smell for smoke around 5-7 minutes. Wait a minute and lift the lid to check the color.
- It’s easy to scorch the coffee by using too much heat, so it’s better to taper off a little after the first crackFirst crack in one of two distinct heat-induced pyrolytic reactions in coffee. It is distinguished by a cracking or popping sound in the coffee, and occurs between 390.... Check color every minute or so.
- You want to pour the beans out of the skillet into a colander when they are a tad lighter than the color you desire since roasting continues until beans are cool.
- Agitate beans in metal colander or bowl with a big spoon until they are warm to your touch. You may need oven mitts for this. You may want to walk out to a porch to aid cooling.
- If beans have light-colored chaffChaff is paper-like skin that comes off the coffee in the roasting process. Chaff from roasting is part of the innermost skin (the silverskin) of the coffee fruit... still attached to them, simply agitating them in the colander should remove it. If you blow lightly on the beans the chaff will fly off but do this outside or over a sink to avoid sweeping the floor.
- Coffee should be stored out of direct light (and not in a fridge or freezer) in an airtight glass jar, but with a fresh roast, wait 12 hours to seal the jar tightly; it needs to vent off C02.
- Warm, fresh roasted beans are wonderful, but the coffee attains its peak about 24 hours after roasting. If you store it as recommended, we’ll call it fresh for 5 days. When you open that jar in the morning, you will know what fresh coffee truly is.
Refinements: Skillet roasting is fun and barbarous, but I must admit, after a while, you can become quite intuitive and produce some good roasts. But in the meantime, you might ruin many good beans. An air popper is 93% foolproof! I have had more success using a wok than a skillet. Still, I am not a talented person with the wok technique. I do know someone who has great success because he uses a wood-type stove and the wok sits in an opening that exposes about 2/3 of its bottom surface area to heat. That means the coffee has more even contact with heat more consistently than on a stovetop range, and the results are very good, so I hear. And he roasts 1 Lb. at a time…
Stovetop Popcorn Popper Method (Stovetop Popper, Victorio / VKP StovePop)
Features: Can produce any roast style, from City roasts to Dark French/Spanish roasts. Lighter roasts are more difficult with this method. Air roasting produces even roasts with less effort, but if you like doing things the “olde tyme way”, you may enjoy this! Beans can be observed during the roast since half the Whirley-Pop lid is hinged and flips up. Since there is no fan or motor, it is very easy to hear the cracks with this method. This is a conductionThe transfer of heat between matter. In coffee, conduction heating is contrasted with convection heating, which occurs in a moving fluid. method and produces a roast close to drum roasting (just smokier since there is no airflow). Can roast 8 oz of coffee at a time. More effort required than a roasting appliance or even an air popper because you have to crank to agitate the beans. And if you don’t like this roast method, the stovetop poppers are incredible popcorn poppers!
What You Need: Victorio / VKP brand popper (our favorite, and most durable type we know), or a Whirley-Pop (previously known as the Felknor Theatre II) or Back to Basics Stainless Steel popper, or another similarly designed device, gas stove (electric with larger burner OK too), a thermometer is mandatory for this method, a metal colander or two for cooling, and oven mitt.
Our Stovetop Roasting Tip Sheet PDF to Print!
PROS: The benefits of Stovetop coffee roasting:
| CONS: The problems with Stovetop coffee roasting:
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Stovetop roasting takes some practice….
There are more variables than other methods since you set the heat and provide the agitation. But the results can be outstanding and the 1/2 lb. batch is nice. It sometimes seems like a 3-handed act: before you start, try a dry-run by adding green coffeeGreen coffee refers to the processed seed of the coffee tree fruit. Coffee is a flowering shrub that produces fruit. The seeds of the fruit are processed, roasted,... without any heat and agitate it. In the course of the roast, agitation gets easier as the coffee loses weight and expands.
Instructions:
- Turn on your stovetop exhaust fan, or open a kitchen window. Have all your supplies within reach.
- Measure out about 8-9 ounces of coffee by weight, or about 12 ounces by volume.
- Use a low flame/medium electric burner setting. NEVER use highest heat settings/flame -you’ll scorch the coffee! See the tip below about using a heat-diffusing cast iron pan if necessary. Heat until thermometer reads about 200 degrees. PLEASE NOTE: A thermometer is going to give an inaccurate reading when the inside of the popper is shiny and reflective, so use a LOWER heat until the popper is broken in and seasoned.
- Put your beans in the popper and start your medium-paced, steady cranking. The thermometer will drop to around 150. Don’t let it drop much below 350 in the roasting process, or get much above 400 except at the end. These temps are starting points; you will ultimately personalize the process once you have done it a few times. And remember, you are measuring the air temperature in the popper, and the actual temperature on the bottom will be higher. DO NOT ROAST BY TEMPERATURE ALONE – watch the beans and popper to be sure the roast is moving neither too fast, nor too slow.
- Around 6 minutes you should hear the “first crack” and see roast smoke. Wait 1 minute and slightly reduce the heat (or lift the popper off the heat), not so much that the roast stalls, but enough so that the roast does not progress too quickly. Start checking the roast by flipping back the lid at about 30 second intervals or less. Second crack ought to occur anywhere from say 9 minutes to 12 minutes, depending on how you like to time the roast. TIP: If you can learn to roast by smell and sound only (and avoid opening the lid), you can reduce escaping roast smoke and any reduction in temperature.
- You want to pour the beans out of the popper into a colander when they are a tad lighter than the color you desire, since roasting continues a little into the cooldown process .
- Agitate beans in metal colander or bowl with a big spoon until they are warm to your touch. You may need oven mitts for this. You may want to shuffle the beans between 2 pans/ colanders.
- You may want to walk out to a porch to aid cooling.
- If beans have light-colored chaff still attached to them, simply agitating them in the colander should remove it. If you blow lightly on the beans the chaff will fly off but do this outside or over a sink to avoid sweeping the floor. Chaff has no flavor so if a bit of chaff remains with the roasted coffee, it is of no real consequence.
- Coffee should be stored out of direct light (and not in a fridge or freezer) in an airtight glass jar, but with a fresh roast, wait 12 hours to seal the jar tightly; it needs to vent off C02.
Warm, fresh roasted beans are wonderful, but the coffee attains its peak 4 to 24 hours after roasting. If you store it as recommended, we’ll call it fresh for 6 days. When you open that jar in the morning, you will know what fresh coffee truly is.
More Stovetop Popper Coffee Roasting Tips:
- If the agitator jams while cranking, don’t force it. Work it free by cranking the opposite direction. When the popper is cool, see if you can bend the agitating tines to hug the bottom of the pan a little closer.
- If the flame is too high, or you worry about burning up the pan, you can use a cast-iron pan, or cast-iron heat diffuser under the pan.
- Having trouble getting an even lighter roast? You need to slow down the initial warm-up period of roasting (from the time you put the coffee in until the first crack).
- Clean the popper with scalding hot water every so often to reduce the coffee oils … it is not necessary to clean it after every roast. I clean mine after every 15-20 roasts.
- VKP Popper jamming once it is heated up? The agitator tip assembly is supposed to have 1/4” free play on the shaft. See the instructions that came with the VKP Popper. You received a small hex head wrench, so just loosen the tiny bolt and adjust the free play. VKP Agitator not turning? The same little bolt might have come loose from the shaft. Use that hex head wrench and tighten it! See our latest article on Stovetop Popper Stirrer Adjustments
Modifications and Refinements:
- We recommend Home Coffee Roasting by Ken David’s for more information. You can use the stovetop popper without a thermometer – but the thermometer gives you more information that can help you make roasts more consistent. Stove popping is great! It’s like cranking an old butter churn or a meat grinder.
- Resist the urge to peek all the time if you can! Listen to the sounds and smell the steam/smoke. After you do this a few times, you’ll know what stage the roast is without looking, which lets a lot of heat escape and makes the kitchen smokier. Remember, first crack sounds like corn popping, while second crack sounds like the snap from an electric spark (or a “snap” in the sense of “snap, crackle pop”).
- When the roast is done, there may be a lot of smoke that makes it hard to judge the color. A good overhead light helps a lot. I keep the popper closed, walk outside with my metal colander, and then transfer the beans.
Here’s a helpful overview of the stovetop process written by Philip Scott-Smith. a home roaster on the island of Guam. It sounds like his initial temperatures are probably too high for the stainless poppers with the Plexi window – unless you have modified the popper and replaced this with a pie plate:
“I believe I finally have the Whirley-Pop method worked outright.
The most important thing to remember is that the W-P is a CONDUCTION roaster. Consequently, the beans always are at risk of scorchingPatches of discolored burn marks on the coffee bean, due to a high-heat roast environment or other roast error.: Scorching refers to a roast error that can be.... Even if the thermometer is reading acceptable temps, it’s easy to get scorched results because simply cranking the agitator doesn’t get them far enough away from the hot skin of the roaster.
Here’s my new method, which has produced consistently superb coffee (possibly even better than my Hearthware roasterA company that makes several of the home air roasters we have stocked: : the Precision (now discontinued), the iRoast (no longer in stock), and the iRoast2 (also...):
- Once the temperature reaches 450*F, I lower the flame to the smallest available (I use a single-burner Coleman stove in my carport). When the temp has stabilized at 500*F, I add 9 oz. of green beans and swirl them for initial, even distribution (swirling as though they were marbles in a covered saucepan). Then, I crank at a moderate speed until I see the temperature start to rise. At that point, I swirl the beans for about 30-40 seconds, keeping the pot’s bottom centered fairly closely over the flame (the swirling mimics some of the levitation we see in fluid bed roasters, and that’s how I got the idea).
- The cycle continues more cranking (faster now), then the next temperature rise, then more swirling, etc…. With each rise in temperature, I crank a little faster after swirling. I take my first look inside the chamber after the first crack. As the temp passes 375* and approaches 400*, I swirl continuously, take one last peek, and dump them in the colander. At that point, they usually are just right for me (Full City/Vienna). If still not dark enough, back they go for a few more seconds. If I’m after a lighter roast (e.g.: Harar), I check the beans more frequently after the first crack. Once I’m satisfied (beans slightly lighter than the desired final color), I shuttle them between two colanders until cool. And that’s it! Fast and furious at the end, but gosh! the coffee’s wonderful. – And there’s a 9 oz. payload for the effort!
Here’s is yet more feedback from a customer on his stovetop popper method – from Bill Baddeley 5/27/05:
I’ve been working with the steel version of the stovetop popcorn popper for the past several weeks, and I’ve gotten to the point of getting consistently good coffee from my roasting efforts. I found a few small glitches as I went along, mostly in the first roast.
•The popper has metal gears on threaded rods. When the agitator began to stick, prior to the first crack, I cranked backward. The gears began to unthread from the rods, so I went back to “forward only” cranking. I put blue locktite (thread sealer) on the threads and replaced the gears, and have had no trouble since. The blue formula allows you to take the gear off if you need to at some later date.
•Shortly after I’d narrowly avoided losing the gears by cranking backward, the clip that retains the handle on the crank rod popped off and rolled away. So, now we’re cranking forward, and being careful not to slip the handle off the crank rod. And we’re mildly apprehensive. I used a 5/16″ O.D. c-clip to retain the handle, and it’s been fine.
•The polycarbonate window sagged when the heat got too high but stayed put well enough to get me through the first batch. I replaced it with a piece of sheet aluminum and that, too, has been fine.
•The thermometer fit through a #8 (8-32) t-nut with the threads drilled out of it. The gasket compound works very well, but I didn’t use enough the first time, and the thermometer AND the t-nut wobbled around, giving me one more thing to try to keep lined up in that first attempt to roast coffee. I used a nut to secure the t-nut to the lid, and then the gasket compound, and it’s been fine since then.
Your advice on listening and smelling the roast as it goes is excellent. It’s much easier than trying to see the beans through the smoke. I had one batch that turned out to be a bit lighter than I wanted, so I poured the beans back into the pot, and roasted them a bit more. I had a couple of roasts that ran too hot and too fast: one so bad I couldn’t drink it. But once you get the hang of it, the roasting process is pretty straightforward. And the coffee is wonderful.