Home coffee roasting adds another dimension to your coffee appreciation. From bean to cup, you can have full control over the roasting and brewing process.
If you want to know how to roast coffee beans at home, this DIY coffee roasting guide is the perfect place to start.
Not only do we share 5 easy ways to roast coffee at home, we also explain the roasting coffee stages and roast levels, what you need to start roasting coffee and considerations when choosing the best way to roast coffee beans at home.
The good news is that while it may take years to fully master all the aspects involved in roasting coffee beans at home, it is easy to get started and you can produce good results in little to no time.
So if you’re interested in roasting your own coffee beans, read on to find out how.
Is Roasting Your Own Coffee Worth It?
Home roasting coffee allows you to expand your knowledge, and you’ll have the freshest beans possible.
There’s no better way to learn about roasting than by doing it yourself, and you’ll also gain a better understanding of varietal/cultivar, region, elevation, processing and other factors.
Home roast coffee also provides good value, as green beans usually sell for $10 to $15 per kilogram.
This is more than the dirt-cheap grounds at grocery stores (which often taste like dirt), but it’s a great price for high-quality coffee.
You end up paying roughly what a mid-level coffee would cost at the grocery, yet the beans are the same quality as what a specialty roaster will use as $10 to $15 per kilo is much less than most specialty roasters charge for their roasted beans.
Whether you roast only a few times or become a regular hobby roaster, most everyone who roasts coffee enjoys learning about the process.
Start out with a basic setup and you won’t regret experimenting with this aspect of coffee preparation. You can then upgrade your equipment if you decide to do this regularly.
The Stages Of Coffee Roasting
At home coffee roasting involves time and temperature, just as any other form of cooking does.
There’s a science to how time and temperature should be used, but it’s first necessary to appreciate what happens to the beans during the coffee roasting process.
The sugars, oils and gases in green coffee beans change as heat is applied to the beans, and these changes create different stages.
Knowing the stages and being able to recognize them is essential to consistently produce good roasts. The main coffee roasting stages are outlined below.
In the first stage of roasting coffee, the unroasted coffee beans take on a yellow hue.
This marks the start of the Maillard reaction, which is an enzymatic sugar reaction that anyone who’s seen a sliced apple turn brown is familiar with.
The sugars within the coffee beans are becoming browned in the same way. In addition to the yellowing color, you’ll also sense a grassy smell at this stage.
The first crack is a faint cracking sound. This is caused by gases escaping from the beans, which occurs at approximately 196°C (385°F). As a result:
- The beans expand slightly, which makes the chaff on them break off and blow away.
- They also become browner, often with a splotchy pattern, as the sugars in them start to caramelize.
- Oils also begin to come to the surface, giving the beans a slightly shinier appearance.
The first crack is faint enough that some noisier roasters will make the sound difficult to hear, so these visual clues can be especially important to recognizing the stage.
The second crack is a more pronounced cracking sound, which is again caused by escaping gases forcing the beans to expand. Changes to the beans include:
- They will be noticeably larger due to the expansion.
- A much shinier look because so many oils have come to the surface.
The smoke will increase and change color, even taking on a blue hue with some batches.
Mythical Third Crack
The mythical third crack features a loud cracking sound that’s soon followed by sirens. You’ll need to call the fire department if you roast this far beyond the second crack …
Coffee Roast Levels
Since the first and second cracks are the result of gases escaping, they reliably occur at certain coffee roasting temperature points.
This makes them the most dependable markers of where a roast is, and most coffee roasting levels are based on these two markers.
The vast majority of roasts end somewhere between the first and second crack, although a few dark roasts extend slightly beyond the second. For reference:
- City Roast (lighter) ends approximately 0:30 to 1:30 after the first crack
- Full City (medium) ends approximately 1:30 to 2:30 after the first crack
- Full City+ (medium-dark) ends at approximately the second crack
- Vienna, French, Italian (dark) end shortly after the second crack.
Anything before the first crack is virtually undrinkable (and often ungrindable), and too far beyond the second crack will create charcoal.
Aim for anything between the first and second crack, and you’ll have a drinkable – and likely decent – cup of coffee.
Moreover, the above time frames should be viewed only as guidelines. Your own setup might require more or less time, depending on:
- The ambient temperature
- Power of your roaste
- The batch size and other factors.
Because individual factors can affect home roasting times, the marks of each stage are a more useful and dependable guide.
Learn the stage characteristics and watch for them, and you’ll be able to consistently roast to a given level with some practice.
Want to roast coffee at home?
We reviewed all the best home coffee roasters to get you started.
How To Start Roasting Your Own Coffee
Roasting your own coffee requires only a basic setup. You will need the following coffee roasting equipment:
1. Green Coffee Beans
Not all local roasters are set up to officially sell green coffee, but many will if you explain that you’re just starting to explore home roasting – roasters love to connect with other coffee fans.
Before purchasing, ensure you understand the difference between coffee bean types so you know exactly what type of coffee beans you are buying.
The U.S.-based Sweet Maria’s is the most well-known green bean supplier for home roasters. They also have a wealth of resources on home roasting.
2. Measuring Instrument
You’ll want something to measure out batches of green beans.
When just beginning, a measuring cup will do if you don’t have a scale.
3. Coffee Roaster
There are numerous options for a home coffee roaster from a simple cast iron skillet to a custom home roasting machine.
We cover the different options below or see our in depth coffee roaster machine reviews here.
4. Cooling Vessel
The coffee beans should be cooled as quickly as possible once they’re roasted.
Appliances that are made specifically for home roasting often have a way to cool the beans down, but you’ll have to get creative if you use a makeshift setup.
Two metal sieves is a great option, and two ceramic bowls can do. You’ll want a pair so that you can move the beans back and forth. Note that anything plastic is likely to melt, so avoid.
5. Coffee Storage Containers
Green coffee beans can be kept in the bags that they come in, although you’re welcome to store them in another container.
Home roasted coffee should be stored in a container that lets gas escape but prevents air from getting in to extend the life of the beans.
Old coffee bags with one-way valves work well as an initial solution (so long as the former coffee in them wasn’t flavored).
If you don’t have a suitable coffee storage container, this one by Airscape is the one I own and highly recommend.
6. Coffee Grinder
The roasted coffee beans will have to be ground before brewing.
Invest in a burr grinder since you’re putting in the effort to roast the beans.
A burr grinder will produce a much more consistent grind than a blade grinder. This allows you to better appreciate an individual coffee, and some burr models don’t cost much more than a blade one does.
If you only drink small quantities of coffee at a time, a manual coffee grinder is an affordable solution.
Considerations For Coffee Roasting At Home
Home roasting setups range from the improvised that makes do with common kitchen equipment to specifically engineered roasting appliances.
There’s no need to purchase a fancy setup if you’re just getting started or don’t have the budget to, but home roasters are available at a range of price points if you do decide to roast regularly.
For each setup, there are many considerations to keep in mind.
Coffee is roasted to between ~196°C (385°F) and ~224°C (435°F), and some dark roasts go even higher.
A roasting setup must generate enough heat to get green beans to these temperatures.
If coffee beans aren’t heated quickly, they’ll lose some of their finer notes and take on a “baked” flavor.
Roasts should be completed within 20 minutes (preferably 15 minutes) to avoid this happening.
Coffee beans ought to be heated as evenly as possible in order to ensure uniform flavor.
A lot of smoke is produced during the coffee roasting process, because the beans are essentially being burnt.
Some roasting-specific appliances have catalytic converters that help mitigate smoke issues, but not all models come with such a feature.
Improvised setups certainly don’t. If you choose a roaster that doesn’t have a catalytic converter (and maybe even if yours does have that feature), roast in a well-ventilated area that smoke won’t harm.
The location you choose should balance the need for ventilation and a reasonable ambient temperature.
Having temperature stability will help you more consistently produce desired roast profiles.
Many home roasting appliances will have difficulty heating beans too quickly if the ambient air is too cold or too windy.
A garage, carport or sheltered outdoor space is a good place to begin roasting, and you can move to a more temperature-stable location if you continue the hobby.
The noise level of a roaster can sometimes be too loud to hear the first and second crack.
While this isn’t insurmountable since there are also visual cues at these stages, it helps if you can hear the two cracks. The first one is especially faint with some beans.
Look for a roaster that lets you see the beans while roasting.
This is especially important if the appliance is loud, but it’s also helpful even if you have a quiet roaster.
The visual cues are often easier to pick up when first getting into the hobby.
Most home roasting setups roast batches of a half-pound or less.
The size of a batch may not matter when starting out, but it could be a factor if you eventually invest in a high-end roaster.
A larger batch size is helpful if you have a large family, entertain frequently or want to give coffee away as gifts.
Coffee bean roasting setups range from the virtually free to the expensive.
A makeshift setup could cost you anywhere from nothing to $75. If you get into roasting appliances, the major price points are at about $150, $650 and 1,300.
10. Other Features
Some roasters have other features, but any additional features are peripheral and not necessary. The other considerations listed above are far more important.
Of all these considerations, heat, speed and evenness are the most important three to keep in mind as you look at different roasting setups.
How To Roast Coffee Beans At Home [5 Ways]
Below are 5 of the most common home roasting setups.
With all of these coffee roasting methods, the beans will “coast” to their final roast level.
Because they won’t cool off immediately, they’ll end up a little darker than they are when you first take them out of the roaster.
1. How To Roast Coffee Beans In A Home Coffee Roaster
Home coffee roasters come at a range of prices and with a variety of features and are the best way to roast coffee beans at home.
Some cheaper models allow you to control only the time, while most provide both time and temperature controls.
Higher-end models may also have built-in and customizable profiles, which allow you to change variables during the roast automatically.
The ones with both time and temperature features give you the same level of precise control, but you must make the adjustments manually during the roasting process.
Steps to roast coffee beans in a coffee roasting machine
You’ll want to follow your home coffee roaster’s specific instructions, but they generally go as follows:
- Measure out your green coffee beans, and put them in the roasting chamber.
- Put the roasting chamber in place, and turn on the roaster itself.
- Select your variables or profile, and begin the roasting process.
- Allow the roast to proceed, making adjustments if your roaster doesn’t have automatic profiles to follow.
- End the roast shortly before the preferred roast level, or allow the roast profile to complete.
- Let the roaster cool down the beans itself if it has a cooling function, or remove and cool in a sieve.
2. How To Roast Coffee Beans In A Popcorn Popper
Air popcorn poppers are popular among beginner and budget-minded home coffee roasters alike.
These appliances are ideally suited for roasting coffee in many ways, since roasting coffee and popping popcorn require the same basic features – heat, airflow, auditory/visual cues, etc. Even coffee beans have a crack or “pop.”
If using a popcorn popper, make sure it’s an air popper and ideally an older model.
Many newer models come with safety shut-offs that prevent them from reaching the temperatures that roasting coffee requires.
Used older models can be found online for relatively little money. Of all the improvised setups, the air popcorn popper is a favorite and probably the best option.
Steps to roast coffee beans with a popcorn popper
- Turn on the air popcorn popper.
- Add a small amount of coffee (don’t fill the full heating chamber).
- Watch as the coffee beans go through the roasting stages.
- Remove the beans shortly before their desired roast level.
- Immediately pour into two sieves to cool the beans down.
The popper’s noise can make hearing the first and second crack difficult, and it can also be hard to see individual beans as they spin around.
The clearest cues to watch for are when the chaff comes off (first crack) and the smoke changes (around second crack).
3. How To Roast Coffee Beans In A Pan
You can also get started easily with a cast iron skillet or heavy-duty frying pan, but be prepared to use the pan only for roasting coffee in the future. You’ll likely ruin even the most heavy-duty pan.
When pan roasting coffee, use an outdoor heat source to avoid indoor smoke issues.
Either a campfire or grill will produce enough heat. Their heat will be varied and the resulting roast uneven, but there are few more fun places to roast than on the BBQ or around the fire.
Steps to roast coffee beans at home in a pan
- Prepare your heat source so that it’s as hot as possible.
- Place a small amount of coffee beans in the pan.
- Put the pan on the heat source, and stir constantly.
- Observe as the coffee beans go through the stages of coffee roasting.
- Remove the beans shortly before their desired roast level.
- Immediately pour into two sieves to cool the beans down.
4. How to Roast Coffee Beans in The Oven
Green coffee beans can theoretically be roasted in an oven, but this is far from an ideal setup.
The amount of smoke produced will almost certainly set off the kitchen smoke detector (even if you have an outdoor exhaust fan).
Plus you won’t have an even roast unless you own a convection oven or stop to stir the beans halfway through – which will greatly increase roast time.
A high-temperature toaster oven that gets up to about 230°C (446°F) is a slightly better option, as you can take this to a garage, carport or outdoors with an extension cord.
Make sure the toaster oven gets up to at least 230°C, though, for any lower maximum temperature won’t sufficiently heat the beans.
Even with this high temperature, you’ll likely have uneven roasts that have a baked flavor.
Despite all of its detractors, however, there’s no denying that an oven or toaster oven is one of the easiest ways to try roasting coffee at home.
Steps to roast coffee beans in an oven
- Preheat the oven/toaster oven to its maximum temperature.
- Place a single layer of green beans on a rimmed metal tray (e.g. cookie sheet, cake pan). Put the tray in the oven once it’s preheated.
- Observe. You may or may not be able to hear the first crack, so also watch for the visual cues of each stage.
- At your desired roast level, remove the pan and place it in the coolest place possible (without putting it on plastic).
- Use a fan to help cool the roasted beans as quickly as possible, tossing them between two sieves once they’re cool enough to handle.
5. How To Roast Coffee Beans In An Air Fryer
An air fryer can work for roasting coffee beans, and it has the benefit of producing one of the most even roasts of all improvised setups.
Many of these devices even come with instructions on how to roast coffee with them. Be sure yours has a way to remove smoke before roasting, though.
Also, you probably don’t want to purchase an air fryer specifically for roasting coffee.
While you can use one if you already have it, your money would be better invested in an actual home coffee roaster if that’s what you want the appliance for.
Steps to roast coffee beans in air fryer
- Heat the air fryer to between 230°C (446°F) and 260°C (500°F).
- Place a single layer of green beans in the fryer’s basket.
- Put the basket in the air fryer, and observe.
- Remove the beans shortly before their desired roast level.
- Immediately pour the beans between the basket and a sieve to cool.
How To Store Freshly Roasted Coffee Beans
Coffee beans shouldn’t be used immediately after roasting.
They contain a lot of gases such as carbon dioxide and need to degas before being brewed.
If you don’t allow the beans to degas for a couple of days, the resulting brew will be somewhat sour and mask finer flavors.
To store your freshly roasted coffee beans, put them in a place that allows gases to escape.
A container with a one-way valve is ideal, and old coffee bags from unflavored selections are a perfect solution.
If you don’t have something with a one-way valve, a paper bag or bowl can suffice.
Whatever container you use, place the coffee in a cool, dry place that’s away from any odors.
Don’t grind the beans until you’re ready to brew with them. They’ll be at their maximum freshness 2 to 3 days after roasting, and they’ll still taste fresh for a few weeks.
Top Tips For A Good Roast
- Purchase the best green coffee beans you can find, for you need good beans to produce a good roast.
- Keep variables as consistent as possible to replicate roasts as closely as possible.
- Pay attention to the temperature if you roast outdoors, as it’ll affect both roast time and cool-off time.
- Get to know a local roaster, and ask them any questions you have about the roasting process.
- Keep roasting, for experience is the best instructor. You’ll get better with each batch.
How To Roast Coffee Beans With Flavor
Although it’s possible to roast coffee beans with added flavors, this is highly inadvisable.
All of your following batches will be tainted by the flavor, and the flavor will almost certainly be too strong in your initial batch.
Rather than adding flavors during the roasting process, infuse flavors into roasted beans by storing the beans next to your preferred flavoring. That way they’ll absorb the aromas and flavor of the ingredient.
How Long Does It Take To Roast Coffee Beans
A batch of coffee beans should be roasted within 15 to 20 minutes, and another 5ish minutes may be needed to cool the beans down.
Some roasting setups that are underpowered take a little longer.
What Is The Best Way To Roast Coffee Beans?
A home coffee roaster will be the most convenient way to roast coffee, and produce the best and most consistent results.
If you aren’t ready to invest in a home coffee roaster, an old air popcorn popper is the best makeshift setup.
We hope you now have a good overview of how to roast your own coffee beans at home.
Roasting coffee at home is a lot of fun, and it gives you an appreciation that you won’t gain any other way.
Get an inexpensive setup and work out how to roast coffee at home. If you want to continue on, you can upgrade your setup as you’re able to.
There’s no need to rush into this, and you’ll have fun no matter how much or little you roast.
You may also like:
- Coffee Roasts Guide
- Why do baristas weigh coffee?
- How to make coffee taste better
- Best coffee brewing methods
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