How to Roast Coffee Beans at Home with a Heat Gun
Let Us Show You How to Roast Coffee Beans
Our freshly roasted coffee beans provide us a perfect espresso or latte every day. The flavours come alive and the rich, dark color makes the coffee look nicer. To a coffee lover, there is nothing quite like it.
The thrill starts about half way through the process as the earthy, nutty aroma is released. The nutty, earthy flavor tempts my taste buds long before I will get a sample. But that's okay, we never allow ourselves to run out.
To be honest, roasting our own coffee beans with a heat gun is much easier than we ever imagined; it saves money while providing better flavor. Once you learn this simple method of how to roast coffee beans, you wont want it any other way.
We have studied several home coffee roasting methods and believe this to be the best. It is quick, easy and our total investment was under $20. After a few trials, we have perfected the technique using only a kitchen pot and a heat gun. This page will show you step by step photos of how we roast coffee beans at home. We also added a few video clips so you can hear the sounds the coffee makes at the various stages.
Coffee Beans Start Out Green
There are many different varieties of coffee beans from many different countries. Our criteria is Fairtrade as it protects the grower and our planet. It is not a brand, but rather a way of doing business. For more information check out: Fairtrade Labelling Organization International
Our current favorites come from East Timor, Sumatra or Guatemalan because they a have rich, non-bitter flavor. Trying out different beans is a great way to determine your favorites.
Step 1: Measuring the Coffee Beans
We generally roast about 200 grams (1 ¼ cups) of the green coffee beans at a time which yields us with about 6 delicious double shot espressos or lattes.
Place the green coffee beans into a stainless steel pot or bowl.
Common Kitchen Items (and a heat gun) Are All You Will Need
The tools of the trade are quite simple. For this method of coffee roasting, all you will need are:
1. Heat Gun (best with 2 heat settings) - see just below for our favorite option.
2. Stainless Steel Saucepan
3. Baking Pan (used for cooling)
4. Oven Mitt
5. Wooden Spoon
You Will Need a Heat Gun
This one has everything you need for the perfect coffee roast:
* Two heat settings: 700F (375C) and 920F (495C)
* Heat resistant cover and ABS housing
* Soften caulking, putty and form plastics, strips paint, varnish & lacquer
* Includes 4 nozzles
Step 2: Find a Spot Outdoors
Roasting beans makes a mess as the light outer layer escapes the beans and scatters all around. We prefer to do this outdoors.
Please Note: The pot will get very hot during the roasting process. You will want to find a spot to place the pot where its bottom won't burn anything. Stones, bricks, concrete or the grill on your BBQ work well.
We use two large stones in a gravel garden.
CAUTION - Heat Guns Get Extremely Hot!
They may look like a hair dryer, but will cause a fire or severe burns. Keep away from children, animals, etc. Be sure to put on a non-flammable surface after use to allow to cool.
Step 3: Stir and Heat
Now you are ready to begin roasting coffee beans.
Be sure to have your oven mitt on and spoon in hand. Turn the heat gun to high and hold it approximately 2-3 inches from the beans at a slight angle. Stir the beans vigorously and continuously with the wooden spoon, while moving the heat gun back and forth over the beans. Do not stop moving the gun or the beans will char and burn.
We added this video so you can see the speed to stir and the proximity of the heat to the beans.
Watch the Color Change from Green to Delicious in 10 - 15 Minutes
Here you can see the color transition the beans will go through as you roast. They start out green in photo #1 and we roast to med-dark in photo #6
Once the beans begin to turn color, as in photo #2, it is time to reduce the heat gun to its lower heat setting. As all heat guns behave differently, you may have to adjust this.
The two videos below allow you to hear the cracking of the beans. The first crack will take place in photo #5, while the second crack is heard when the beans reach the color of photo #6.
First Crack Sounds
As the beans get closer to being done, they go through a first crack. The beans are actually expanding, and they make a sharp cracking sound as water escapes in the form of steam.
Keep stirring and heating through this process. We only stopped heating for the 2 second video, so you could better hear the sound.
The beans will continue to heat and sugars will caramelize, oils will evolve, and a more muted second crack can be heard. This sound indicates you are almost done for a medium to dark roast.
Again, keep stirring and heating through this process. We only stopped heating for the 2 second video, so you could better hear the sound.
If you want a medium dark roast, like photo #6 above, stop the heating while second crack is in progress.
Finally, Cool Down Your Beans Quickly
Immediately after turning off the heat gun, pour beans into a cooling tray. We use a flat baking pan with edges so the beans can spread out, but not fall of the edges. This prevents the heat from concentrating. The beans will continue to roast themselves and overcook as long as they are hot.
Into the refrigerator they go!
Now That You Have Learned How to Roast Coffee Beans - Are you going to give it a try?
Are you going to roast your own coffee beans?
Our Favorite Book About Coffee
The Art and Craft of Coffee is the perfect title for this book. We have read many books on coffee and this one is our favorite book about coffee book. It tells it all and as a bonus, it looks great on the coffee table.
We have one for ourselves, but it would make a great gift for any coffee lover, or anyone who is thinking about brewing their own.
Wait Before You Brew
Freshly roasted beans should set for 12 hours before grinding and brewing to get the maximum flavors.
After the Roast
The roasting process will increase the volume of the beans while decreasing their weight. Typical weight loss is 12 - 20%. Without a scale this would go unnoticed.
Once cooled, store your beans in a glass jar in the refrigerator. They say they are best if used in the first week. Ours have never lasted longer than this, so we can't verify that anything happens to the flavor.
© 2009 Rhonda Albom