How Do I Get Started Roasting Coffee?
At Coffee Bean Corral, we’d love to help you get from green coffee beans to a piping hot, freshly roasted cup of coffee. Because the perfect cup of joe is a matter of a coffee lover's personal taste, we want to help you get a handle on the entire roasting process. When you understand how it all works, you’re that much closer to roasting your perfect tasting bean and brewing the right cup for you. We’ll look at the different types of roasts and then explore the process of creating them. Here are a few overall tips to get you started:
- Take Notes - Developing the perfect cup of coffee is an art form. But, when you stir in a little bit of the scientific process, you’ll be more likely to keep on creating masterpieces. So, keep a record of your roasting. Keep track of your process and rate your favorite creations. Be sure to document the amount of beans, the temperature (and any variances), the time, and the type of beans you used.
- Research - Get to know your particular roasting machine. Different machines have different nuances, so learn your machine and be sure to use it properly.
- Know Your Beans - No two types of coffee beans are the same. Check out our Coffee Bean Matrix for an extensive primer on different attributes of various beans. It’s an easy way to research, compare, and purchase your beans, all in one place.
- Keep It Fresh - Remember, roasted coffee beans are only considered fresh for 7-10 days. So, keep it fresh, and drink up!
Types of Coffee Roasts
As coffee beans roast, several important chemical changes occur that affect the taste of the bean. Perhaps the most notable change is that the beans darken in color the longer they’re roasted. It is by this most obvious change that we classify each roast type. Let’s take a look at them in turn, considering the distinguishing features of each roast. Notice that the acidity level of the bean goes down during the roasting process, while the bitterness increases.
- Light Roast
- Color: Light Brown
- Sheen: Dry and dull, with no oil on the bean
- Flavor: Fruity and mild, with stronger acidity. Some feel like this roast has a grassy undeveloped taste. This roast has a strong aftertaste, that some prefer and other do not.
- Names: Cinnamon, Light Roast, Light City or Half City
- Medium Roast
- Color: Medium brown
- Sheen: Dry and dull, with no oil on the bean
- Flavor: Stronger, fuller flavor than the light roast beans. Less aciditic than the light roast with a strong aftertaste.
- Names: City, American, or Breakfast
- Medium-Dark Roast
- Color: Rich, darker chestnut brown
- Sheen: Some beans start to develop some oil (some don’t)
- Flavor: This roast style is considered by many to be the ultimate roast: the perfect balance point in terms of brightness, aroma, full body and varietal flavor characteristics (which is what you see on our coffee matrix). Coincidentally, this is the roast style most home roasters end up adopting as their favorite, especially those who initially liked the shiny, dark roasted beans they used to buy in the store.
- Names: Full City or Vienna
- Dark Roast
- Color: Dark brown to black
- Sheen: Somewhat shiny and oily to very shiny and oily
- Flavor: This roast style is not acidic but has a pronounced bitter taste. The smoky flavors of the roasting process are more pronounced.
- Names: Espresso, Italian, French, High, Viennese, or Continental
The Roasting Process
The process of roasting coffee beans is hundreds of years old. One legend tells of a weary mystic who was sustained and revitalized in the desert by coffee. When he returned home with the “miracle drink”, he was actually proclaimed a saint. While brewing a good cup of coffee may not always result in sainthood, there are rewards for the bold and persistent roaster. So, let’s roll up our sleeves. We’ve got some sacred work ahead of us!
Start Your Engines
Once you fire up your roaster, the beans will start to move. Depending on your roasting method and machine, you may or may not be able to see this. We’ll explain the process as if you can see the beans, even if you need to rely more on hearing and practiced timing to get your beans out at the proper moment. During this first part of the process the water in the beans starts to evaporate, and the chemical decomposition of the sugars (pyrolysis) is occurring. The beans get brighter, then turn yellowish and emit a wonderful smell. Don't stop yet though, unless you like drinking straw or lawn clippings.
There is, however, a special type of roasted coffee that's known as white coffee, which is roasted at lower temperatures than most coffee beans and for a longer period of time. The roasting process is stopped right before the first crack which results in a coffee bean that appears white, hence the name. The coffee bean itself is still hard and dense, so grinding it properly is of the utmost importance. This style of roasting results in a bean that has a pronounced acidity with a nutty flavor.
First Crack in the Roasting Process
Green coffee beans are full of water, and that water is getting ready to explode. As the heat level in the roaster rises, the water begins to turn to vapor. When that water vapor escapes, the beans expand, creating a cracking or popping sound. This “first crack” will sound like popcorn or breaking toothpicks and will be irregular in cadence. Beans will expand to roughly twice their green size but lose about 15% of their weight. At this point in time, the beans will begin to “float” in the roasting chamber and turn a light brown color. Stopping after first crack produces a light roast coffee bean. Because the sugar in the beans have not started to caramelize, light roasted beans do not have the same sweetness that you'll find in beans that go through the second crack. If you want to try a light roast bean, follow the tips below.
- Cinnamon Roast - This is the lightest roast. Stopping just after the first crack will produce this roast. The beans will be light brown and dry. Named for its cinnamon color when ground, this roast tastes somewhat grassy and slightly underdeveloped.
- City or American Roast - This roast is often called the American because Americans prefer this roast. To achieve this roast, stop after the first crack has ended and just before the second crack begins. The beans will be still be dry and dull but will have a darker brown than the cinnamon roast. This roast has a stronger and fruitier taste than the cinnamon roast.
Second Crack in the Roasting Process
People who prefer a medium-dark to dark roast need to really pay attention during the second crack in the roasting process. To many, this is where the magic happens and because it happens quickly, you will want to be ready to stop and cool your beans at just the right moment. The second crack starts slowly and is not as loud as the first crack. You’ll start to hear a soft staccato cracking sound almost like the sound of bacon sizzling. This is the sound of the actual cell walls in the beans breaking down and releasing carbon dioxide and oils. Little flecks of beans (called chaff) begin to break off the beans. It’s during this stage that the sugars in the coffee beans begin to caramelize, creating a sweeter flavor. Here are some guidelines for achieving the different types of roasts at this stage:
- Vienna/City Roast - Stop roasting at the beginning of the second crack. The beans will have some oil on them and be chestnut brown. For many home roasters, this is the perfect stopping point.
- Espresso - Stop when the beans are dark brown and oily but not quite shiny for this roast.
- Italian to French - For these darkest roasts, stop when the beans are oily and almost black. At this stage the sugars have stopped caramelizing and have started carbonizing which gives them a smokier taste.
- Charcoal - This is not a roast. You went too far and burned the beans. It’s possible, and it doesn’t taste good. But, there’s always next time. So, go back to start.
Curing or De-Gassing Your Coffee Beans
No one wants a gassy bean! So, give your beans a rest. You may not realize it, but this is the last stage in the roasting process. Beans need to cure in order to let all the extra gasses out and to develop a full flavor. This takes a minimum of four hours and up to twenty-four. Some swear that twelve hours is the perfect cure-time for flavor development. Regardless of your preference, it’s a good idea to give it those beans a rest. Once they’re cool, keep your beans in an airtight container during the curing process.
Storage and Use
While resting is good, there comes a time when resting turns to retirement, where freshness is gone, and your beans become stale. There are diverse opinions regarding when staleness begins to set in, but somewhere between 7-10 days is a good marker. The reality is that coffee beans starts to degrade as soon they reaches peak flavor. So, here are some general tips for storing your freshly roasted coffee.
- Storage - Keep your coffee beans in an airtight container in a cool dark place.
- Grinding Guidelines - Grind your coffee right before you brew it. Unless you’re going camping, you shouldn’t need to grind your coffee until just before use. And, be sure to clean out your grinder between each use. Built up coffee grinds will be stale and embitter your fresh coffee.
- Brewing Guidelines - However you choose to brew, use clean tools and good tasting water. Also, don’t use boiling water. Water boils at 212˚F. But coffee is best brewed between 195˚F and 205˚F. So, if you boil your water, let it sit a couple of minutes before you brew.
Why Buy Green Coffee Beans?
You may be saying to yourself, “This seems like a lot of work! Why should I go green?” The proof is in the pudding, or rather, the coffee. The best tasting coffee is the freshest coffee. And since ground coffee starts to go stale rather quickly, roasting your own coffee will give you the best cup! Green coffee beans don’t lose their freshness like already roasted beans. It’s only after a coffee bean is roasted that the time starts to tick towards staleness. When you buy a bag of already roasted beans at the grocery store, those beans have already peaked in flavor long ago.
So, if you want a fresh roasted taste, you must take matters into your own hands. The good news is that there is a coffee roasting renaissance in America. And, Coffee Bean Corral is an early leader in this trend. You can easily order green beans and roast your own. Check out our coffee bean matrix to get started.