Pre-roasted coffee beans have become incredibly popular, but for true coffee lovers, few things in life are more enjoyable than coffee brewed with freshly roasted beans. Learning to roast your own makes it easy to enjoy this delicious treat any time you want, without having to leave your house (or spend $5 on a single drink).
There are also a few different ways you can roast coffee beans at home, based on what tools you have at home. The most popular method of home roasting uses a gas grill with a side burner. You can also roast your beans with a hot air popcorn maker or on the stove with a frying pan.
The Different Roasts
You might think that different roasting methods are used for each type of roast, but this isn't necessarily true. The roast you get depends mainly on how long you roast the coffee beans, not the equipment or type of bean you use.
There are six main roasts:
This is the lightest roast, when the beans turn a cinnamon color towards the end of the "first crackle". This produces a very light coffee with low acidity.
Occurring immediately after the first crackle ends, the American Roast is ideal for people who want a not-so-strong coffee experience. You'll also notice the smell of the beans change at this point, exuding the distinctive aroma of caramel. American Roast coffee has a mild sweetness to it that many people love.
Distinguished by a rich medium brown color, City Roast beans have a fuller, mildly sweet flavor and body. This is also when the acidity of the beans begins to rise.
Full City Roast
Also referred to as light French roast, this is when you start to really get the bittersweet roast flavor, the Full City Roast has a good balance between body, acidity and sweetness. This occurs right as the second crackle begins.
More commonly known as French roast or espresso, this dark roast occurs right at the end of the second crackle. At this point the acidity is muted and the coffee will have a strong, bittersweet taste.
Sometimes called Italian coffee, this is when the beans are extremely dark, almost black, a few minutes after the second crackle ends. These beans have low sweetness levels, a mild scent, and a weak body.
Roasting Coffee Beans with a Grill
You will need a gas grill (charcoal grills rarely get hot enough) and a stainless steel popcorn popper for this method. If you already have both, you can roast your own coffee by completing the steps listed below:
1. Preheat the Grill
Let the side burner heat up for about 10 minutes; some people suggest preheating the popper with the burner. The grill should get to somewhere between 240ºC and 275ºC.
2. Add the Beans
Fill your popper with beans and stir them consistently with the hand crank, doing one rotation every 3-4 seconds. Many people leave half of the lid open so they can see the progress of the beans, which should slowly turn yellowish-brown.
3. Listen and Watch
After about 10 minutes you'll notice a series of sharp cracking or popping sounds that sound almost like popcorn. You can pull the beans out now for a very light, tea-like experience, but most people suggest waiting for the second set of cracks a few minutes later. These cracks are much lighter sounds, so you need to pay careful attention once you hear the first set.
The color of your coffee beans at any given point during the roasting process is another good way to determine what your coffee will taste like. The darker the beans get, the stronger they will taste. Roasting continues during the cooling process, so you should remove the beans when they're a shade or two lighter than you actually want.
Most people prefer either light French roast, Vienna Roast, or regular French roast. For a light French roast, you want to pull the popper off the grill as soon as the second crackling phase begins. To get the perfect Vienna roast, pull the popper off the grill as soon as the second crackle ends. For a regular French roast experience, you want to wait until the beans are dark brown and it's been 2-3 minutes since the second crackling phase ended.
4. Let them Cool
When you're satisfied with the color of your coffee beans, remove them from the grill and dump them on a cookie sheet, spreading them out to form a single even layer. The beans expand a lot during the roasting process, so it will look like you have many more beans than you did at the beginning.
You want to let the beans cool for at least an hour. Some recipes call for as much as 12 hours, but this doesn't make a significant difference to the taste.
5. Brew or Store Beans
Now you can either grind up your coffee beans for a delicious pot or store them in an airtight container for later use. A properly airtight container will let them retain their freshness longer, but you still want to use them as quickly as possible.
Roasting Your Coffee Beans with a Hot Air Popcorn Maker
Air roasting coffee beans with a popcorn maker is quickly becoming the most popular way to roast coffee beans because it produces an extremely even roast. This method is most effective for roasts between light French roast and Italian coffee.
It should be noted that not all hot air popcorn makers can roast coffee. You need a model where the hot air enters the popcorn maker through the sides, and one with a solid base. The most commonly recommended poppers are the Nostalgia Electric Popcorn Popper, the West Bend Poppery II, and Hamilton Beach's Popaire 2.
Once you've picked up the right popper and an aluminum colander, you're ready to roast your own coffee using the following steps:
1. Set Up the Popper
The coffee beans will emit smoke as they roast, so you should set the popper up in a well ventilated area, such as beside a kitchen exhaust fan or a window. If possible you should also have a bright overhead light so you can watch the coffee roast. All of your supplies should be laid out within easy reach.
2. Turn It On
Pour your green coffee beans into the popper's main chamber. As they enter the chamber they'll start to spin around. Your popper is full when the beans are barely able to move. Most poppers can handle about 4oz. of beans.
3. Put the Lid (Including Butter Dish) On
Some of the cheaper popper hoods will warp somewhat after a while. Mild warping is fine, but if you notice significant warping, stop usage immediately.
4. Put a Bowl Under the Chute
This bowl will collect the chaff (flakes from the outer layer of the bean). You can put water or a wet paper towel in the bottom to help the chaff stick. Depending on how your kitchen is set up, you may be able to skip this step by putting the popper near the sink so chaff flies directly into the basin.
When your coffee is roasted, you'll hear a string of crackling sounds, similar to the sound of popcorn cooking. This should happen after around 4 minutes, and means your beans are officially roasted to the lightest level.
Once your beans are almost the color you want them (they will roast further as they cool), pour them out of the popper. Ideally you should do this with one quick movement, without turning the popper off. If you do turn the popper off, pour the beans out immediately, as the edges of the heated popper will burn coffee quickly when it isn't moving.
6. Stir Until Cool
Pour your beans into a metal colander and stir with a large spoon until they are cool enough to touch. You may want to wear oven mitts during this part of the process.
8. Store or Brew Beans
Your coffee is now ready to be ground or put into an airtight container for storage! Keep it away from direct light and heat.
Roasting Your Coffee with a Frying Pan
This method of roasting coffee beans doesn't require any special equipment—all you need is a frying pan, a metal colander, a pair of oven mitts, and a big spoon—but it's one of the most difficult methods to get right. You will likely have to do it several times before you make the perfect coffee roast.
You can roast your coffee with a frying pan by completing these steps:
1. Set Up Your Roasting Area
Your exhaust fan should be on and any available windows open. You should also have all the tools you'll need for roasting within easy reach, as you need to pay careful attention during the roasting process.
2. Measure Your Coffee Beans
You want the pan to be fairly full, but it should still be easy to stir your coffee beans without making a mess. For most pans you should start with ½ of a cup, adding more if necessary.
3. Preheat the Pan
Set your oven on the medium setting and give the pan a few minutes to preheat.
4. Pour in the Beans
Pour the beans you've measured into the pan and begin stirring with a big spoon. You'll want to stir every 2-3 seconds to keep the beans moving for an even roast.
5. Watch and Listen
You should see a steady progression from light to dark. The first set of crackling sounds will begin after about 5 minutes of cooking. At this point you can pull the beans for a light, almost tea-like roast. After a few more minutes, as the beans turn from light brown to dark brown, you'll notice the beginning of a second set of crackling sounds. You can pull the beans at this point for a light French roast or wait until the crackling ends for an Italian style coffee.
6. Dump the Beans
Dump the beans into the colander mentioned before and stir the beans until they're cool enough to safely touch. The chaff (the skin of the beans) will be discarded through the holes in the colander, so make sure it's placed on some kind of receptacle or outside during this process.
7. Let Them Cool
At this point you need to let the beans cool off and finish the roasting process. Spread them out on a baking sheet in an even layer and leave them for 1-12 hours.
8. Brew or Store the Beans
Now your coffee beans are ready to go! You can grind them up for a fresh pot of coffee right away or store them in an airtight container. Either way, keep them out of direct light and heat until you're ready to brew them.
Roasting your coffee at home can be as simple or as complicated as you want it to be, and all of these roasting methods have similar results if done right. The air popping method isn't very good for light coffees, but otherwise the biggest difference between the three popular home roasting options is how much energy and equipment is involved in each one.