How to Roast Green Coffee Beans – Tips, Tools, and Instructions

Why Should I Roast My Own Coffee Beans?

Roasting your own batch of raw green coffee beans is an incredibly fun hobby that you can share with friends and family. To be successful, you’ll want to arm yourself with the right tools and instructions to make a delicious batch of coffee. Here are some great reasons to roast coffee beans at home:

  • First, green coffee beans store longer than roasted. If you like to stock up on supplies for a rainy day, roasted coffee beans are a poor choice as they deteriorate significantly after six weeks. As a matter of fact, most of the roasted coffee on store shelves has already lost much of its flavor profile and nutrition. Green beans on the other hand will store for up to two years in a burlap bag in the right conditions. And unlike the roasted, they won’t lose an ounce of their flavor.
  • Second, roasting your own beans is not nearly as hard as those snooty coffee aficionados make it sound. It also doesn’t take that long. Usually only about 20 to 30 minutes per batch once you have gotten past the learning curve.
  • It costs between a quarter and half as much to purchase quality beans unroasted and roast them yourself. The costs savings for quality are astounding.
  • You can add your own flavor. If you’re a fan of hazelnut or French vanilla, flavored coffee is hard to resist, but the flavorings that major manufacturers use may not suit your pallet or perhaps they use chemicals that you don’t want to put in your body. When you roast your own, you control how much flavor to add and what ingredients that flavoring contains. You should add flavors while the beans are warm, not hot, so you don’t burn off the taste. You can use professional flavors that your order online, or simply add some fresh vanilla extract to your beans and toss.
  • It’s fun! This is the best reason to roast your own beans.

What Type of Equipment Do I Need to Roast Coffee?

The type of equipment you need depends on the roasting technique you choose. You don’t necessarily need expensive equipment to roast your own beans. You can roast beans on a stovetop with a large pan, in the oven with a metal vegetable steamer, with a hot air popcorn popper or with a coffee roasting machine. Before you invest in an expensive machine, you might want to try one of the simpler methods first. It’s quite an adventure to roast your own beans the way they did over a hundred years ago. We have a list of best roasters for home use here.

 

How to Select Your Beans

All coffee beans are unique, but the area that they are grown in tends to contribute basic characteristics to the beans. You can browse a full selection of green coffee origins.

Brazil

These are the strong beans used for espresso and dark roasts. They have a chocolate feel and flavor. You can see available Brazilian green coffee beans here.

Central America

Beans grown here tend to have a fruity undertone and are rather light. They are good for the lighter roasts. You can find a great selection of Colombian green coffee from this region.

Ethiopia

The plant originated here, and these are the masters of the brew. There are many varieties from dark to fruity. You’ll just have to experiment with this region. View available Sidamo green coffee here.

Kenya

These are the bold beans. They are fun to mix with Central American for extra depth and flavor.

Hawaiian

Hawaiian coffees are sweet and mild. They have a floral bouquet that is quite unique and fragrant.

Indonesia

Smoky beans with a chocolate, bitter aftertaste make for a beautiful full-bodied bean to add to blends. They are unique and interesting on their own as well. Indonesian Sumatra green coffee has characteristics of spice, earth, and grapefruit.

 

How to Roast Green Coffee Beans

First, coffee should be roasted in a well-ventilated area because it produces smoke. Make sure you have 30 minutes of completely uninterrupted time. You have to watch the beans very closely because they reach their peak roast very fast, and they go from nice and bold to burnt and ruined even faster. You probably won’t get your first batch exactly right unless you are the type to have beginner’s luck, so don’t start out with an extremely expensive bean. Get a few pounds of less expensive (but still good) beans to practice on and work with them in small batches till you get the hang of it. Try about half a cup at a time.

Next, you should know the basics of the roasting process. There are several steps to roasting your beans. If you learn them well before you start, you will know when they are properly done and how not to burn them.

 

Here are the 7 steps to roasting the perfect bean:

 

1. Yellow

During the first few minutes, the beans smell rather, well, green. They start to emit a smell like fresh cut grass as they move from green to yellow.

2. It’s getting steamy

Your beans will start to emit steam as they dry out and the last of the steam in them dissipates.

3. The 1st Crack

This is when your coffee starts to smell like coffee. 1st crack is what every roaster watches for to know when the seconds start to count, much the same as you listen for the first pop of popcorn. This is the point at which the sugar in the bean caramelizes and the oil in the bean begins to move toward the shell. If you have ever made homemade candy, you know that the time difference between the hard crack stage, at which you would have nice hard candy, and the burned caramel stage is measured in mere seconds even at lower temperatures. It’s exactly the same with coffee beans. When that first crack occurs, you must be very vigilant with your eyes, ears and nose so you don’t burn the whole batch.

4. The City Roast

Just shortly after the first crack occurs, you have a nice, light city roast. You can actually stop the process right here if you like lighter coffee or this is the style of roast recommended for the beans you chose.

5. Full City Roast

When you are on the verge of the second crack and you notice that the beans are caramelizing, this is when you develop a fuller bodied city roast.

6. Vienna Roast

The second crack hits a lot harder than the first. It sounds a lot like when popcorn popping starts to take off in full. At this point, the flavor of the roast really starts to outshine the bean. The carbohydrates in the bean are becoming fully caramelized and a rich, bold flavor begins to develop.

7. Dark Roast

This is many a roasters favorite stage. It’s also the riskiest because the step right after this is fresh roasted charcoal. The difference between a cup of full bodied dark roast and a cup of ashes can be measured in seconds. This nice dark roast occurs at the end of the second crack, just before the sugars are completely burned. If you like a nice dark cup, this is the stage to master.

 

Different Ways to Roast Coffee

 

Stovetop roasting

For stovetop roasting, you will need a large skillet with a lid. This process is not recommended with an electric stove because you may burn the beans. Turn the flame up to medium and heat the pan. Add about 1 cup of beans, put the lid on and start shaking the pan like you are making popcorn. After about five minutes, the beans start to make a cracking sound. They will change color very fast at this point, so you must watch them very closely. It’s easiest if you have a glass lid. Otherwise, lift the lid and peak at the beans about every 60 seconds. To get the beans to their desired color, you must remove them from the heat a little bit before they reach the color you want. Coffee beans continue to darken after being taken off heat. This fun method is one heck of a workout and it roasts the beans somewhat unevenly, depending on how much you shake the pan while they are roasting. If you are a fan of the nuances in flavor created by less even roasting, this method will give you a lot of room for subtle experimentation.

 

Oven roasting

 

Do you have one of those little stainless steel vegetable steamers that fold open? This is oddly the perfect tool for roasting coffee. Heat your oven as high as it will go. Place the beans in the open steamer, and leave it in the open position, don’t close it up. Then place it on a cookie sheet and place it in the center of the oven. Open the oven every minute to stir the beans for a more even roast. In about five minutes, after you hear the first crack, you will need to check the beans every minute for color. Remove the beans just before they reach their desired color.

Hot-air popper

 

You can roast the same amount of coffee in your popper as you can popcorn. For most manufacturers, that’s around one half cup to a cup. Put the lid and butter dish on the popper and start the machine. Light roasts take about 4 minutes. Medium roast takes roughly 5 minutes. Dark and bold roasts take around 6 minutes. Of course, you will need to go by smell and appearance of the beans. You can check the color by lifting out the butter dish and peaking every minute or so. As with the other methods, you want to pour out the beans just before they reach the color you want.

Custom coffee roaster

 

This is the way to get the most consistent roast because you can control the temperature precisely. It’s also the least adventurous. But those who are truly ready to start roasting their own coffee all the time usually end up purchasing a professional roasting machine.

 

How Much to Roast and When

Most coffee types are at peak flavor at between 7 to 14 days after they have been roasted, so it’s best to roast your coffee one week before you need it. Only roast as much coffee as you need for one week so you always have the freshest roasted beans.