Are you looking to try roasting coffee at home? Perhaps you want to limit your spending at Starbucks. Or you may be looking for a way to elevate your everyday coffee routine. Whatever the reason, we want to help you learn how to roast coffee beans at home.
In this article, we’ll learn whether it is truly possible to roast your own coffee beans at home, why you should even attempt to do so, and coffee roasting terminology. We will also delve into a step-by-step guide on home coffee roasting.
Can You Roast Coffee In Your Home?
It is 100% possible to roast coffee beans at home. While it is an intricate and detailed process, it is not complicated. As a beginner, you can learn to roast your coffee fast and enjoy the fruits of your labor. When you master the simple roasting method, you can invest in a more professional home coffee roaster and play around with the parameters to get different flavors like experienced coffee roasters.
There are several methods to roast your beans for the perfect brew. You can choose to use the inelegant but efficient popcorn popper or purchase a high-tech roasting machine. You can also use a pan over the stove or the oven to roast beans. We’ll go through each method you can use to get freshly roasted coffee beans at home.
Why Roast Coffee at Home?
Is roasting your own beans worth it? We think so, and many coffee lovers agree with us. There are numerous benefits to roasting beans at home.
Firstly, learning to roast your coffee is a great skill to pick up. In fact, by the time you’re confident in your roasting skills, you will have picked up other skills along the way. Learning to roast coffee does not take a long time and is a fun and engaging process.
Roasting your coffee also offers you more control. You can pick your ideal roast level and control the flavor of your coffee. Using your beans and picking the roast method and time allows you the freedom to enjoy your ideal flavor complexity. You can have your coffee as sweet and smokey or earthy and complex as you want it.
Another advantage of roasting your coffee is that you get to enjoy fresh coffee at home. You’ll enjoy the rich flavor of freshly roasted beans and the numerous health benefits of added antioxidants.
Also, who doesn’t want to look like a culinary magician? Home-roasting coffee gives some bragging rights at the dinner table. It is also a great conversation starter whenever you want to break the ice.
What’s the Coffee Roasting Process?
The home coffee roasting process starts with green coffee beans. Roasting is turning the green coffee beans to brown using heat. We do this to extract over 800 aroma compounds that form the flavor profile of the coffee. There are three stages in the home coffee roasting process:
Green coffee beans have a humidity of around 8–12%, depending on their growing environment. Before you start roasting the raw coffee beans, you need to dry them. Drying takes anywhere from 4 to 8 minutes with a drum roaster.
When drying your green beans, ensure the temperature is not too high to avoid burning the beans. The drying stage collects energy from the fresh beans to use in the last roasting stage.
The second stage is where you’ll notice the rich color of coffee develops on the beans. Drying will continue during the browning stage as the beans begin releasing flavor. You will notice the aroma precursors as the Maillard reaction begins.
The browning stage of the home-coffee roasting process is the slowest part. Slowing down the process and agitating the beans ensures flavor development and allows roasters to pick their ideal roast level.
The roasting or development stage begins at the first crack, at around 384°F. You will hear a cracking sound like that of popcorn kernel popping. You will start to notice the depth of the aroma of the coffee at the development stage. The beans will expand and pop, giving off smoke. Here is where roasters get to choose their ideal roast level.
You’ll achieve light roast coffee if you stop the roast after the first crack. Light roasts have no oils and have the most caffeine and acidity since the beans have lower temperatures of 384°F to 401°F. It is also called a city roast and can taste citrusy.
Slowing down the development stage but continuing the roast until just before the second crack will give you a medium roast or full city roast. The beans have an internal temperature of 410°F to 428°F. They have more body and slightly less acidity and an earthy flavor. Medium roast is considered balanced by many coffee drinkers.
You’ll achieve a medium-dark roast if you stop roasting the beans during or just after the second crack. You will notice oils on the beans due to the high temperatures of 437°F to 446°F. Medium-dark has a fuller flavor and body with less acidity and a slight smokiness.
The final roast level before burnt is dark roast which is between 464°F and 482°F. Dark roast coffee doesn’t have the original flavors of the coffee bean. It is sweet due to the sugars in the coffee caramelizing. The flavor is decadent and smoky. French roast and Italian roast are darker roasts.
After development, you need to cool beans fast to finish the roasting.
Coffee Roasting Terminology
Here are some coffee roasting terms to help you familiarize yourself with the process:
Pre-heat or Charge: This is a critical stage for home coffee roasters. Pre-heating is where you run your home coffee roaster of choice at a high temperature for a long time. It gets the metal, glass, and other particles off the roster to allow for the energy to be focused on the roasting process.
Roast Profiling: The process of documenting data on the roast, such as times and temperatures. It helps show patterns and results, making the roasting process easier with time.
Drying Stage: The first roasting stage is marked by heating the raw beans to get enough energy for the remaining stages.
Yellow Point or Dry End: Towards the end of the drying stage, the green bean takes on a pale yellow color. It occurs when the internal temperature in the beans is between 300°F and 320°F.
Maillard Reaction: Marks the start of the browning or caramelizing stage. It is when amino acids and reducing sugars react, creating hundreds of aromas and colors known as melanoidin.
First crack: It happens because of an exothermic reaction where the coffee beans release built-up energy and steam. Marked by a distinct “pop” sound, it marks the start of the development stage.
Second crack: A more rapid pop that happens a few moments after the first crack to release the buildup of carbon dioxide. How long it takes for the second crack depends on the roaster, bean type, and the size of the roast batch.
Agitate: The process of moving the beans around gently but firmly to help release more flavor and achieve an even roast
Dropping the coffee: Releasing the coffee out of the roasting chamber or turning off the heat and turning on the fan to cool the coffee.
Drop temperature: The temperature at which you conclude the roast.
Chaff: Dried skin around green coffee beans that falls off when exposed to high temperatures
Degassing: A natural process where freshly roasted coffee beans release pent-up carbon dioxide gas rapidly. Home roasters allow for at least 24 hours of degassing before cupping.
Cupping: The tasting exercise used by roasters to determine the quality of the coffee and roasting technique.
A Step-By-Step Guide To Roasting Coffee at Home
Here is a simple and easy-to-follow guide to home coffee roasting:
Step 1 – Purchase Green Coffee Beans
Buying green beans is the first step in roasting coffee beans at home. When buying unroasted coffee beans, there are several factors to consider, including the coffee’s origin and altitude, the beans’ size and appearance, and the processing and drying methods used.
Different regions produce coffee with unique flavor profiles and strengths. Here are some examples:
- Coffee beans from East Africa are fruity, aromatic, and flavorful. If you enjoy coffee with higher acidity, you can find high-quality coffees from Ethiopia and Kenya.
- Central America is a popular coffee-growing region. Beans from Costa Rican and Guatemalan are particularly sought-after.
- Papua New Guinea, South America, New Guinea, and Indonesia are also major coffee-producing regions. You can also try premium beans from Hawaii Kona or Jamaican Blue Mountain. Here is a list of the best coffee beans in the world. You can find more detailed information on each coffee-growing region there.
Additionally, it’s important to look for beans that are similar in size, shape, and color, which indicates proper sorting and classification.
Also, look for certified sustainable and ethically sourced coffee, such as Fair Trade and Rainforest Alliance certificates. Here is a guide for coffee certifications.
You can purchase green coffee beans online, at your local coffee shop and coffee roaster, or directly from growers in the regions mentioned.
Step 2 – Prepare a Roasting Space
When deciding where to roast, you should consider what roasting method you’ll use. With a popcorn machine and pan over stove methods, you should ideally be outside as the heat can be too much and cause a fire.
Don’t roast near power outlets if you choose to roast your coffee indoors. Always use an empty surface and ensure you are near an open window or a fan.
You will need your roasting method of choice as well as a metal colander for cooling. You will also need oven mitts and a fan if you can find one. The fan helps with cooling the beans and your roasting space. Additionally, the chaff may fly around, so you’d better have a vacuum cleaner.
Step 3 – Choose Your Roasting Method
There are four typical home coffee roasting methods you can use:
1. Popcorn Popper
Popcorn machines can get hot enough to roast coffee. Ideally, you want to use an older one with air vents along the inside wall of the roasting chamber to achieve your home roast. If your popcorn popper has a mesh screen on the bottom of the chamber, don’t use it because it can catch fire.
- Setup in a well-lit and ventilated area, like under a stove hood or near an open window.
- Keep all your needed accessories near you. The popper gets hot fast, and you can end up with burnt coffee beans.
- Measure your coffee beans with the same measurement for popcorn which is about half a cup.
- Place the lid on the roaster and position the chute over your chaff container.
- Turn on the popper and watch it like a hawk. Do not leave it for even a second.
- Listen for the first crack, which will happen after 3 to 5 minutes. If you want a light roast, turn off the popper and use a colander or fan to cool the beans.
- Wait another minute or two for the second crack if you want a dark roast. Between the first and second crack, you’ll get medium and medium-dark roast coffee.
- Moderately affordable compared to high-end roasters
- Can be too fast and burn the coffee bean
- Can’t use a new popcorn popper
- It’s a fire hazard
2. Pan Roasting On Stove
As the name implies, this method involves using a cast iron skillet on the stove for home coffee roasting. You can also use a skillet, round-bottomed wok, or soup pot. We recommend the round-bottomed wok as it distributes heat more evenly. You also want to use a metal pan with no coating, like stainless steel or cast iron.
- Ensure all your equipment is within easy reach.
- Turn on your exhaust fan or any other fan if you have one. If you don’t, try this outside or with your windows open.
- Measure enough coffee beans. They should fit at the bottom of the pan, and they should be easy to stir.
- Turn on your stove and pre-heat your pan to about 500°F
- Pour in coffee beans and immediately start stirring gently. Keep the beans moving to agitate them.
- Notice the gentle but rapid color progression from green to pale yellow, and then golden brown within the first 5 to 6 minutes. Keep stirring.
- After five minutes, you will hear the first crack. Take it off the heat and cool it in the colander for a light roast.
- The beans will steadily change color from golden to light brown in 8 to 10 minutes. Adjust the heat accordingly to maintain an even roasting progression
- Wait for the second crack and watch as the color darkens if you want a dark roast.
- Remove the beans at whatever point you want between the first and second crack for a medium and medium dark roast.
- Use a colander to cool and turn off the gas or electricity.
- Affordable and easy
- Offers steady and safe heating
- Easy to follow with minimum risks
- Must stir beans continuously
- High risk of burnt or unevenly roasted beans
3. Oven Roasting Method
If you’re wary of stirring, try the oven method. You’ll need a steamer or perforated oven pan and an oven that heats well and to high temperatures.
- Pre-heat your oven to 500°F.
- Place your coffee beans in the steamer of a perforated pan.
- Put them in the middle rack of the oven on the cookie sheet.
- Close the oven door but remain near to open the door every minute or two to agitate the beans.
- You’ll hear the first crack after about five minutes, and you can turn off the oven and cool the beans if you want a light roast.
- Check the color of the beans every minute for a medium or medium dark roast, or wait for the second crack to remove the beans.
- Place roasted beans in a metal colander and shake to cool swiftly, and remove the chaff.
- Easy and with minimal work
- It can be too slow
- Cannot quickly change the roasting temperature
- High chance of an uneven roast
4. Coffee Roasting Machine
You can get perfectly-roasted coffee with a high-tech roasting machine. There are many home coffee roasters available at a wide price range and offer different functions.
- Purchase a home coffee roasting machine you like within your budget.
- Read manual.
- Follow the manual instructions.
Each roasting machine is different and instructions vary.
- Allows for you to set roast level
- Does all the agitating
- Better performance, more even roast
- Can be expensive
- Can be very complicated for high-end machines
- Have a learning curve
Step 4 – Cool and Store Your Coffee
You need to cool your roasted beans to keep them from continuing to roast. As long as they’re hot, they continue roasting and it will impact your roast level. Also, cooling for at least 24 hours before using is crucial to determining the quality of your roast. It allows for degassing, which ensures perfect flavor.
Once fully cooled, store your coffee in an airtight container and place it away from direct sunlight or heat. It should remain in a cool and dry place.
Tips for Avoiding Common Roasting Mistakes
When roasting coffee at home, there are a few common mistakes people make:
- Using too little heat: To ensure proper flavor development and even roasting, ensure you use a proper amount of heat
- Undeveloped or overdeveloped roasts: Whatever roast level you want, allow airflow after you lower or remove heat. It allows for the remaining heat to continue developing the flavor without comprising the roast level.
- Not Pre-heating equipment: Always pre-heat to ensure enough heat is available for roasting
- Not taking notes: You need notes so you can refer to them in the future as you finetune your home roasting process
- Drinking too fast: Give your roasted beans at least 2 hours to de-grass so the flavor can develop before you start using them
- Unclean equipment: Clean whatever you use to roast regularly, ideally after every roast to avoid impacting the flavor of your next roast
Can Your Roast Coffee Beans at Home Without a Machine?
Yes, you can use the pan, oven, and popcorn popper to roast your coffee beans at home. These methods are heavily involved and require your absolute attention. You cannot turn away, and there are no pre-set settings.
The safest of these methods is the oven, but it’s hard to adjust the temperature. Using the pan over the stove allows temperature adjustment, but it can lead to uneven roasts, and it’s easy to burn yourself. The popper is quick but a fire hazard.
Home coffee roasting is simple but perfecting it takes time. Once you have selected your ideal green beans and decided on your roasting method and roast level, you’re good to go.
Ensure you pick the right environment to keep yourself safe, and follow a tutorial to ensure you get your ideal roast level. Don’t forget to store your fresh roast in an airtight container and place it in a cool, dry place. Remember that it takes time and practice to perfect roast your coffee.