Roasting Coffee Beans at Home – How You Can and Why You Should

Coffee has been consumed for many hundreds of years, but commercial coffee roasting only took hold in the mid 1900s. Before that, roasting coffee beans at home was the norm. Even though at-home coffee roasting has fallen out of favor in modern times, coffee lovers are showing renewed interest in learning the process. And for good reason. Coffee doesn’t get much fresher than when you roast it yourself. So let’s explore what’s involved in roasting coffee beans at home (hint: it’s much simpler than you think!) and why it’s so very worth the effort.

The Reason for Roasting

Before we learn how to roast our own coffee, it’s helpful to understand why roasting is required in the first place.

Roasting is the process by which hard, unpalatable raw coffee seeds are transformed into the flavorful, aromatic beans used to make our daily brew. Green coffee beans are exposed to heat and “cooked” until they become brown.

light to dark coffee beans

But why is this so important?

Simply put, without the browning process — also known as the Maillard Reaction — coffee beans would remain too bitter for consumption. It’s the same basic chemical transformation that makes baked bread or browned meat more tempting to our taste buds.

Suffice it to say that pretty much everything we love about coffee is dependent on the roasting process.

A Brief History of Coffee Roasting

Coffee as a beverage has been enjoyed for many hundreds of years. That means coffee roasting has been around just as long. Even our ancestors understood that great tasting coffee required careful roasting.

Ancient Coffee Roasting Tools

The oldest coffee-roasting tools date all the way back to the 15th century. They were basically small, shallow metal pans fitted with long handles that made it possible for them to be held over an open fire or hot coals until the coffee beans browned. The ensemble also included a long-handled spoon that was used to stir the beans to keep them from burning.

15th century coffee roaster

In the 17th century, crank-handled cylindrical coffee roasters first appeared. These devices allowed the coffee beans to be kept in constant motion while over the heat source. This not only reduced burning and scorching but also produced more evenly-roasted beans. Which, of course, brewed up better-tasting coffee.

wood stove coffee roaster

Since hand-cranked roasters offered the best results, inventors continued to improve the design through the years. Gears and handles were refined to provide smooth, easy movement of the roasting drum. Heating elements were incorporated into the design which allowed for greater temperature control while roasting.

antique coffee roaster

All of the first coffee-roasting tools developed were designed for individual use. This meant that only a small amount of coffee could be roasted at one time. For this reason, roasting coffee beans was considered a routine household task, one that was repeated every few days or so.

Commercial Coffee Roasting Catches On

It wasn’t until the 19th century that inventors turned their attention to creating large-scale commercial roasters. Yet even as late as 1850, commercial coffee roasting was a bit of an oddity. Roasting coffee beans at home was such an ordinary part of life that no one thought it necessary to do things differently.

The trend finally began to shift away from home-roasting only as recently as 1864. That’s when the innovative Arbuckle Brothers began packaging and selling one-pound bags of their commercially-roasted coffee beans. Both the convenience of pre-roasted coffee beans and their consistent quality were instrumental in turning popular opinion.

commercial coffee roaster

By the 1950s, specialty coffee houses began to appear, many of which roasted their own coffee beans. These establishments sparked the “gourmet coffee movement” by selling a variety of coffee beans from around the world in an array of roast levels. It didn’t take long for coffee lovers to be hooked.

Since coffee houses could acquire shipments of coffee beans in bulk for less money than individuals could, it became increasingly cheaper — as well as more convenient — to enjoy better-quality coffee by letting someone else do the buying and roasting of the beans.

Home Roasting Makes A Comeback

Although commercial coffee roasting is now well established, the art of roasting coffee beans at home is far from lost. In fact, it has been a growing hobby among coffee aficionados in recent years. This is, in part, thanks to the advances in modern transport which makes it both fast and affordable for anyone to acquire high-quality raw, green coffee beans.

Benefits of Roasting Coffee at Home

But why bother roasting your own coffee beans when pre-roasted coffee is so readily available? The answer in three words:

  • Freshness
  • Flavor
  • Fun

Freshness

We know that grinding our own coffee beans provides us a fresher-tasting beverage than using commercially pre-ground coffee. So it’s only natural that the most ardent coffee lovers among us would take that quest for freshness a step further by roasting their own coffee beans at home.

coffee beans in silver cup

For those of us who aren’t growing coffee at home or processing our own coffee cherries, roasting is the first step of coffee production we can access and control.

As noted, raw coffee beans from around the world are readily available these days from either local roasters or by mail order.

And, as we’ll explore a little further on in this article, a variety of common kitchen tools can be used to do the actual roasting. One does not have to invest in any fancy or expensive equipment.

All in all, roasting coffee at home is a surprisingly accessible process.

The reward for your efforts is that you will rarely enjoy a fresher or more-satisfying cup of coffee than the one made from beans you roasted yourself.

Flavor

As we learned in The Difference Between Coffee Roasts, the level of roast creates a wide array of flavor experiences.

The problem is, when we purchase commercially-packaged coffee, we’re typically stuck with a whole pound of that particular roast. That makes experimenting with different roasts a bit risky.

It’s great to have a pound of coffee we love, but what if we discover we don’t care for it? That same pound of coffee will seem to last forever.

I know because I’ve been there!

Once you decide to roast your own coffee beans, however, you take complete control over the process. You choose the level of roast and the size of each batch.

light to dark roasted coffee beans
What Level Roast Do You Love?

Maybe you’ve been curious about the flavors inherent in a cup of light-roast coffee. Perhaps you’ve wanted to explore whether the burnt-notes of the darkest roasts truly appeal to you. Or maybe you’d simply like to try all the roasts levels in sequence from lightest to darkest.

Whatever your coffee-enjoying goal, roasting coffee beans at home will give you the freedom to experiment in small, personalized batches. That’s far better than having to make yourself drink an entire pound of coffee you just don’t like.

Fun

For the most passionate coffee lovers, roasting coffee beans at home is an enjoyable hobby. There is something deeply satisfying about transforming raw coffee beans into a delicious cup of coffee.

What makes it all more fun is the ease and simplicity with which it can be done. Sure, you can invest in an expensive home roaster, study the science behind the process, and make yourself crazy monitoring every variable from temperature to time.

Or you can buy some raw coffee beans, grab a cast iron skillet, a baking sheet, metal colander, or a hot-air popcorn popper (yes, a popcorn popper!) and have some fun!

But First, Coffee Safety!

Before we dive into specific roasting instructions, we first need to cover a few topics related to safety. Roasting coffee is a relatively quick and simple process, but there are a few things you’ll need to know and keep in mind before you begin. Please read through the following information carefully. It will help you enjoy a successful and safe coffee roasting experience.

  • VENTILATION IS REQUIRED! While they are roasting, coffee beans give off a lot of smoke. So it is vital that they be roasted where there is plenty of ventilation. Open windows and use a small fan to circulate the air while you roast. Better still, roast your coffee beans outside on a grill or over a fire.
  • IT’S A BIT MESSY. When coffee is roasted, the thin silverskin surrounding the coffee bean dries and comes off, creating what’s call chaff. Chaff is similar to tiny wood shavings, and it can make a bit of a mess in your roasting and cooling area. So expect there may be some clean-up needed when you’re done roasting. (Special Note: Coffee chaff can be used in small quantities as composting matter for your garden).
  • IT REQUIRES FOCUS. The time that it takes for coffee beans to go from raw to perfectly-roasted to burnt-beyond-use is typically 10 minutes or less. So when those beans hit the heat, you’ve got to be focused on the roasting process 100%. To avoid burnt beans and a potential fire, never roast coffee while you’re distracted.
  • YOU’LL NEED TO LISTEN CAREFULLY. To get the best results, it’s important to understand what’s happening when your coffee is roasting and what you should be looking for. HINT: It’s not about the color, it’s about the sound! As you roast, you’ll need to be listening for the first and possibly second “crack” that the beans will make. First crack indicates the lightest palatable roast level has been reached. Second crack means your beans are dark-roasted and on the verge of burning. Monitoring the time between the two cracks will help you determine when the beans reach your most-desired roast level. We recommend the roasting levels chart on Wikipedia to help you along.
  • COFFEE BEANS WILL CONTINUE ROASTING AFTER BEING REMOVED FROM THE HEAT SOURCE. So you should stop the roasting process on “the light side” of your ideal roast level by a minute or so.
  • ROASTED COFFEE BEANS SHOULD BE COOLED IMMEDIATELY. The best method is to have two metal, long-handled colanders available in which you can pass the hot beans back and forth right after roasting. This will not only cool the beans but also separate out the chaff. *CAUTION: Roasted coffee beans are crazy-hot, so use extreme caution during the cooling phase!* Because of the chaff, you’ll want to “colander toss” the beans outdoors if at all possible so the chaff can simply fly away. If you have to work indoors, though, hold the colanders over a sink or bathtub to help contain the chaff for easier cleanup. You can also lay the roasted beans out on a baking sheet to cool, but this will slow down cooling process significantly (allowing the beans to continue roasting longer) and will not remove the chaff.
  • ROASTED BEANS WILL OFF-GAS FOR A FEW DAYS. Even after they are cool to the touch, freshly-roasted coffee beans continue to give off carbon dioxide for many hours. Because of this, it is important not to tightly seal your coffee beans for at least 12 hours after roasting. If you close them up too soon, your container might burst.
  • STORAGE AND USE. Once the roasted coffee beans have cooled for at least 12, you will then want to seal them up tightly. Glass canning jars work great, but be sure to keep the jar away from direct sunlight. After another 12 hours, your coffee beans will be ready for grinding and brewing. For best flavor and ultimate freshness, use your home-roasted coffee beans within a week.

One last suggestion before you begin roasting is to read through our article How Is Whole Bean Coffee Roasted? This will familiarize you with the process from start to finish. The better you understand what’s taking place when you roast, the better your results will be.

What You’ll Need

Once you’re ready to try roasting your own coffee, you’ll need to gather the following supplies:

  • Raw Coffee Beans – You can buy raw coffee beans from a local roaster or order them online. You’ll need two pounds of raw, green coffee beans for every one pound of roasted coffee you’d like to produce.
  • Roasting Tools for the Method Being Used:
    1. For Oven or Grill Roasting: A Metal Colander, a Baking Sheet, and a Heat-Resistant, Long-Handled Spoon; OR a Baking Sheet and a Spatula
    2. For Stove Top or Open Fire Roasting: A Cast Iron Skillet and a Long-Handled, Heat-Resistant Spoon
    3. A Hot-Air Popcorn Popper and a Heat-Resistant Bowl
  • Two Metal, Long-Handled Colanders for Cooling
  • Oven Mitts
  • Storage Jar

Roasting Coffee Beans at Home

Below are the instructions for three different ways to roast coffee beans at home without investing in an expensive coffee roaster. While none of these methods is perfect, they are perfectly suited for experimentation.

If you discover you love roasting your own coffee beans, then you may find it’s worth your while to invest in a home coffee roaster.

Or you may find one of these methods suits you just fine indefinitely.

Oven or Grill Coffee Roasting

  1. Pre-heat your oven or grill to 500 Degrees.
  2. If using an indoor oven, turn on the range vent, open windows, and turn on a fan for adequate ventilation.
  3. Spread raw coffee beans in a single layer on a baking sheet OR place half a cup to a cup of raw beans in the metal colander and set the colander atop the baking sheet.
  4. Put the beans in the oven or on the grill rack to begin roasting.
  5. Allow the beans to roast for 2 – 3 minutes, then use the spoon to stir the beans if they are in a colander or steamer basket or flip them with the spatula if they are roasting directly on the baking sheet. Do this as quickly as possible to minimize heat loss.
  6. Stir or flip the coffee beans approximately every minute.
  7. Listen for the First Crack as this will tell you that the lightest roast level has been reached. The beans can be removed any time after this point dependent upon the level of roast you desire.
  8. Listen for the Second Crack if you continue roasting. Remove the beans soon after the second crack is heard as they will burn quickly after this point and become unusable.
  9. Immediately after removing the beans from the heat source, begin cooling them by passing them between two metal colanders as described in the “Safety” section above.
  10. When cool to the touch, place your roasted coffee beans in a storage jar or canister but do not seal them tightly for another 12 – 24 hours.
  11. Twenty-four hours after roasting, you can grind and brew your beans.
coffee beans unevenly roasted

Note that using an oven or grill to roast your beans will generally produce the most uneven roast of the three methods we’re covering here. Some people find this adds an interesting complexity to the flavor of their coffee. If it doesn’t appeal to you, however, we suggest you try one of the roasting methods described below.

Stove Top or Open-Fire Coffee Roasting

  1. Pre-heat your skillet on the stove top or on a rack placed over your fire until the is extremely hot.
  2. If using an indoor stove, turn on the range vent, open windows, and turn on a fan for adequate ventilation.
  3. Add raw coffee beans to cover the bottom of the skillet.
  4. Begin stirring the coffee beans immediately and continue stirring throughout the roasting process to produce an even roast.
  5. Listen for the First Crack which should occur at about the 3-minute mark. The beans can be removed any time after this point dependent upon the level of roast you desire.
  6. Listen for the Second Crack if you continue roasting. Remove the beans soon after the second crack is heard as they will burn quickly after this point and become unusable.
  7. Immediately after removing the beans from the heat source, begin cooling them by passing them between two metal colanders as described in the “Safety” section above.
  8. When cool to the touch, place your roasted coffee beans in a storage jar or canister but do not seal them tightly for another 12 – 24 hours.
  9. Twenty-four hours after roasting, you can grind and brew your beans.

Hot-Air Popcorn Popper Coffee Roasting

Although not specifically designed for roasting coffee, hot-air popcorn poppers are generally ideal for the task. The downside is that using your popper to roast coffee will void any warranty on the appliance, so proceed only if you’re okay with this.

Another issue is that a hot-air popper will only be able to roast a small amount of coffee beans at a time, usually 2/3 – 3/4 cup (follow the manufacturer’s instructions, replacing the recommended amount of popcorn kernels with your raw coffee beans). Since most people don’t eat popcorn as frequently as coffee drinkers drink coffee, your popper will end up getting quite a workout and may not last all that long.

All that said, hot-air popcorn poppers are generally inexpensive, often available at thrift stores, and provide a great way to discover if roasting coffee beans at home is something that really appeals to you.

Here’s how to give it a try:

  1. Plug in the popcorn popper in a well-ventilated area, preferably on a porch or deck. If roasting indoors, open windows and use a fan to dissipate the smoke.
  2. Measure out your raw coffee beans as per the manufacturer’s instructions for the popcorn kernels (generally this will be 2/3 – 3/4 cup maximum).
  3. Pour the raw beans into the hot-air chamber.
  4. Replace the hood of the popper and place a bowl under it to catch the chaff that will blow out as the coffee beans roast.
  5. Turn on the popper and wait for it to heat and begin roasting.
  6. Listen for the First Crack which should occur at about the 3-minute mark. The beans can be removed any time after this point dependent upon the level of roast you desire.
  7. Listen for the Second Crack if you continue roasting. Remove the beans soon after the second crack is heard as they will burn quickly after this point and become unusable.
  8. Pour the beans out of the popper and immediately begin cooling them by passing them between two metal colanders as described in the “Safety” section above.
  9. When cool to the touch, place your roasted coffee beans in a storage jar or canister but do not seal them tightly for another 12 – 24 hours.
  10. Twenty-four hours after roasting, you can grind and brew your beans.

Now that you’ve successfully roasted your coffee beans, there’s one very important thing left to do:

Enjoy!

black coffee in white mug on coffee beans

Have you tried roasting coffee beans at home? If so, what method did you use and how did it work out? We’d love to hear about your experience in the comment section below.

14 Comments

  1. Laureen

    Thanks Cheri! This is the deepest insight I’ve read about the production of my everyday energy booster, being a coffee drinker myself for the past 10 years! However I’m a bit confused and uncomfortable when it comes to getting started (as I can’t do basic cooking at all haha), is it safe to roast just a very small amount of raw beans in a normal size oven, because I wanna slowly test how the process will turn out? I might be doing this for a few times with minimal beans (in case they go into waste) before actually producing for consumption.

    • Cheri

      Laureen I think it’s wise for anyone (even if they can do basic cooking haha) to start with small batches of beans, maybe half a cup to a cup at first. That way you can watch, listen, and learn from the process of roasting your coffee beans without risk of ruining too many beans (they do cost us money, after all!)  and to be sure you have all your “safety measures” in place (particularly plenty of ventilation for the smoke). Once you’ve successfully roasted a few smaller batches of coffee beans, then you can roast at a higher volume. If you want. You may find you prefer the outcome with roasting small batches of beans more frequently. Thanks for commenting, and I hope you enjoy the process!

  2. Dave Sweney

    I am an avid coffee fan and have been for years. Roasting beans at home is something we do and it has grown into an art of sorts. Depending on the beans we use, the roast we select, and the mix of beans, we have come up with some great recipes over the years that make a wonderful cup of coffee, and all from home!

    What you have researched and put together in this article is super interesting to me, and I learned so much. It is one thing to roast your own coffee, but to know the history of roasting and coffee is to enjoy the process to a greater degree, at least for us (I have had my wife read this as well).

    The home roasting process you have laid out is very similar to what we have worked out over the years. Most definitely you want to practice safety at all points, we have had some near disasters over the years we have roasted our own coffee beans.

    Part of the joy of roasting your own beans is creating a blend of beans and the degree of roast that provides the ideal cup of coffee. That is a never-ending journey, as we like to try different beans and blends to find new tastes that we get from our roasts. 

    A wonderful article and a joy to read, thanks for putting so much work into this… For the persons that may be thinking of roasting their beans at home, I can only say “Get started today, you will not be sorry!” especially if you love great tasting coffee!

    • Cheri

      Thanks for taking the time to comment, Dave. It’s great to hear from someone who is actually roasting their own coffee beans at home. I definitely agree that roasting one’s own coffee beans is an enjoyable artistic process. 

      In researching this article, I did come to realize how important it is to be mindful of safety, both while roasting (where heat and smoke can cause a problem) and even in the initial storing of the roasted beans (where off-gassing can cause a sealed container to pop open or even burst). That’s why I felt it imperative to highlight the potential issues one might have during and after the roasting process. I’m glad none of your “near disasters” turned into anything serious!

      Personally I love the fact that so many aspects of enjoying coffee are “never-ending journeys.” There’s just so much to experiment with and so many flavors to experience.

      Thanks again for commenting, and I hope you’ll visit again.

  3. MissusB

    I am a coffee lover. I can’t make my day right without coffee, but now I realise I don’t have much knowledge of my favourite drink. Maybe I should try your methods of roasting it instead of relying on what coffee houses have to offer. You are right, fresh products are incomparable to anything. Your procedure doesn’t seem hard to do, except for the cleaning part. Even the materials and tools are readily available. I just have to purchase my coffee beans. Next time, can you tell us the distinct taste of coffee around the globe? Thank you for this. Just like my coffee, it made my day!

  4. Ginger

    I absolutely loved this article. I am a huge coffee drinker, but I have never roasted it myself. I really gathered a lot of information from your post, and I believe I just might try to do some coffee roasting at home. It seems fairly easy, and I love fresh, flavorful coffee. Thank you so much for the information.

    • Cheri

      I’m glad you enjoyed the post, Ginger, and I hope you enjoy roasting coffee at home if you give it a try. Thanks for visiting and commenting!

  5. Daniel

    Hi Cheri, I must say that this article is very helpful and informative. I have never done that before but why not. Freshness is also very important so I will definitely try this at home. May I ask if I can share this article on my Pinterest profile? I know that there are people who would like to learn this.

    • Cheri

      Daniel that was my reaction when I first realized how accessible roasting our own coffee beans can be…Why not?! It’s a learning process that takes a little practice, but since absolutely everyone used to to it, there’s no reason we can’t now, too, despite being used to simply buying pre-roasted coffee beans. I hope you’ll let me know how it goes if you give it a try. And I’d be honored to have you share the post on any of your social media (which reminds me that I started to add those SHARE buttons then ended up with a plugin that didn’t work…need to get that resolved…thanks for the nudge). I appreciate your visit and comment.

  6. Bex

    I am a huge fan of learning about the history of things and I especially enjoy a vintage vibe – I was so pleased and interested to learn of the history of coffee roasting and the photographs of the vintage coffee elements were especially appealing and of great interest.  I have never considered roasting coffee at home before but the way you have clearly laid out the process involved as well as the safety measures one must take and what to expect. This is so cool!  I will share it with some girlfriends and see if this something we can endeavour upon!  Thank you tons for this inspiring and valuable content!  I bet your house smells so yummy with that delicious fresh coffee smell!

    • Cheri

      I enjoy learning about the history of things, too! It’s one of the reasons I started this site, because I began learning how truly fascinating (and tumultuous!) the entire history of coffee really is (and on that note, you might be interested in some of the crazier things I’ve discovered in my research that I turned into the article Strange Coffee Facts – 12 Things You Never Knew About Your Daily Brew.)  I particularly enjoy inspiring coffee lovers to learn more about what they are drinking so they can expand their enjoyment. Roasting coffee is so much more accessible than people realize, and can be quite a fun project. I hope you and your girlfriends will give it a try sometime. Please let me know how it goes if you do. And, as for my house, well, we live in a small cabin, so coffee roasting is definitely an outdoor-on-the-grill project or we would always walk around smelling like Starbucks! I do wonder what some of our rural neighbors think when the aroma of coffee suddenly wafts around them, though…haha  Thanks so much for your comment, and I hope you’ll visit again. 

  7. Hi, Cheri, what a captivating article! I never considered the possibility of roasting my own coffee at home but what a fun idea! I love that you offered three different methods for roasting and that none of them sound very difficult. I may have to invest in a hot-air popcorn popper specifically for this purpose. I like the idea of roasting the coffee beans outside but since I don’t have a grill, this sounds like a nice alternative and less messy than the other options. I can’t wait to try it! I’ll let you know how it goes. Thanks for the inspiration. 🙂

    • I’m so glad you’re inspired to try roasting coffee beans at home for yourself now, Theresa. I think it sounds like great fun, too, and look forward to trying it myself. Since I know I can’t handle smoke in the house at all, I’ll have to do my roasting outside. We will definitely have to compare results once we’ve given it a go. Thanks so much for reading and commenting. I appreciate you!

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