Raw coffee beans are green. However, coffee companies pack and sell them to consumers after roasting. It is hard to get green coffee in a store. Besides, you will rarely find someone who likes to brew and drink raw coffees.
Now the question is; why are coffee beans roasted?
In this article, we will cover the reasons for roasting coffee beans, its process, and other essential facts.
Let’s read and explore.
Do Coffee Beans Need to be Roasted?
We must confess that the heavenly aroma and flavor influence us to drink coffee. The tang of coffee is like hidden treasures. Roasting is the only way to discover the relish from coffee beans.
Green coffee beans have a grassy smell. They are also highly acidic. So, if you brew them, you will experience a raw leafy flavor. That’s why it is essential to reduce the acidic attributes and make beans consumable.
Raw coffee beans are very difficult to grind because of their water content. A high-temperature roasting dries up the watery properties of coffee beans and extracts the perfect flavor through chemical changes.
The process saves coffee beans from moisture. Moreover, roasting lets us grind and brew coffee beans easier.
Difference between Roasted and Unroasted Coffee Beans
Roasted and unroasted coffee beans are not only different in colors. After roasting, they get unique characteristics, flavors, and formations.
Check the following chart to understand some key differences between roasted and unroasted coffee beans.
| Unroasted coffee beans | Roasted coffee beans | |
| Color | Green. | They look yellowish to dark brown after roasting. |
| Price | Raw coffee beans are cheaper than roasted beans. | Roasted beans cost higher comparatively. |
| Taste | They have an intensely bitter and acidic taste. | They have an excellent aromatic and smoky taste. |
| Acidity | Green coffee beans are highly acidic. | Roasted beans have less acidity. |
| Caffeine | They have a high level of caffeine. | They lose caffeine content when roasted. |
| Flavor | Raw coffee beans have almost no flavor. | Roasted coffee beans have beautiful and different flavors. |
How are Coffee Beans Roasted?
Coffee bean roasting has some precise steps to achieve the ultimate quality. Though we mostly buy readymade pre-ground coffee from stores, you can roast raw coffee beans at home for the freshest taste.
You will need a coffee bean roaster machine to do it. Let’s check out every step of roasting coffee beans at home.
Step 1:
Collect fresh green coffee beans and prepare your roasting machine. You should place the roaster machine outside or somewhere with proper ventilation.
Note: Roasting inside a roofed room can hold the irritating smoky smell for longer.
Step 2:
Put green coffee beans into the machine’s roasting chamber. To avoid wastage, take raw beans according to the brewing volume.
Note: Roasting will release the watery substances from beans and make them lightweight. So, don’t measure raw coffee as you would roasted coffee.
Step 3:
Cover the machine’s roasting chamber with its lid and set the temperature to 140°C. Now, switch on the roaster machine.
Note: Coffee beans are usually roasted at 188 to 282 °C. Since the beans are raw, we recommend starting roasting at 140°C.
Step 4:
Keep roasting the beans until they become yellowish. This stage can take 10 to 15 minutes. You should also notice water steam on the roaster’s lid.
Step 5:
When green beans turn yellow, increase the temperature to 180°C and continue the roasting. After a few minutes, you should hear the first cracking noise from beans.
Note: The cracking noise signifies that the beans are lightly roasted. But, you should roast them an additional few minutes.
Step 6:
After hearing the first crack, set the roasting temperature to 220°C. In this stage, the color of the beans will change.
Step 7:
Now, it is time to roast coffee beans according to your taste and flavor preference. If you want lightly roasted beans, keep roasting about 5 to 7 minutes more from the first crack.
After a few minutes, coffee beans will make a cracking noise again. For medium roasted beans, you need to roast those 10 minutes more from the second crack.
If you prefer a dark roast, keep roasting for about 20 minutes and stop when the beans look dark and oily.
Step 8:
After ending the roasting, move the beans from the roasting machine to a metal colander. This stage is essential to cool down the roasted beans.
Step 9:
When the roasted beans become cooled, leave them for up to 48 hours since they will release intense gas. You can keep roasted beans in an air-tight container after the duration.
Different Methods of Roasting Coffee
There are two commercial coffee roasting methods.
- Drum roasting
- Hot air roasting
Drum Roasting:
It is a traditional way of roasting coffee beans. In this process, coffee beans are directly roasted in heated drums for 15 to 20 minutes.
Coffee roastmasters keep the temperature at 180 to 230 °C to remove acidity from beans.
After accomplishing the roasting, they blow cold air to cool down the roasted beans faster.
Hot Air Roasting:
This method is a modern way of roasting raw coffee beans faster. It is cheaper and more convenient than traditional roasting methods.
Here, coffee beans are roasted for 1 to 5 minutes only at an extremely higher temperature, like 700 °C.
Finally, roastmasters use cold water to cool down the roasted beans.
Though hot air roasting is cheaper and faster from the commercial perspective, traditional drum roasting is still invincible in case of quality.
Frequently Asked Question
Final Words
So, we came to know finally why coffee beans are roasted. Roastmasters do it to take out the mind-blowing aroma of coffee beans. You can also roast beans at home. However, coffee professionals have brought roasting to art by amplifying the aroma.