Effect of coffee bean roasting on coffee flavor how should Costa Rican coffee beans be roasted?

Roasting is one of the most important and influential steps in transforming coffee from green beans to ripe beans that can be brewed. Why do we drink coffee some bitter, some with fruit acid, some nuts, caramel, chocolate flavor, is determined by baking!

The main purpose of roasting coffee is to rapidly heat green beans to produce many chemical reactions, including thermal decomposition, Maillard reaction and caramelization, which bring aroma and flavor. A similar reaction occurs when baking our favorite bread or cookies.

The differences between different baking styles are very large, because each brand, each baker has its own unique views and likes and dislikes. Most commercial baking is done in a rotor-type roaster, the size of which depends on the limitations of the machine and the amount of processing desired by the baker. Some machines bake only a few hundred grams at a time, while others can process tens of thousands of grams of beans. A tumble roaster acts like a dryer, heating coffee beans tumbling inside the drum through a combination of convection and conduction. The process from the moment the beans enter the drum to the moment they finish roasting and are poured into a cooling pan varies according to the roaster and the degree of roasting, but generally takes 10 to 15 minutes.

The roasting temperature of coffee beans varies throughout the roasting process, reaching a high of 232 degrees Celsius towards the end of roasting. The key to coffee roasting success is being able to monitor and manage these temperatures over time. Once roasters lose control of these variables, there is a risk of consistency and quality in each pot of coffee roasting.

Near the end of the roasting process, when the taste of the coffee begins to change, the gases formed in the coffee beans expand rapidly and make an audible popping sound as they escape from the beans, which we call the "first pop". The first burst occurred at 193 degrees Celsius, an important indicator for bakers. Most light to medium roasted coffee beans finish roasting shortly after this burst occurs.

If the target is a deep roast, the temperature will continue to rise and the beans will experience a "second burst" at about 223 degrees Celsius. Most specialty coffee beans finish roasting before the second crack occurs. Coffee beans roasted to or beyond the second crack belong to the field of deep roasting, and the roasted flavor replaces the original flavor of the coffee beans.

Once the beans are roasted to the desired degree, a door at the bottom of the roaster opens and the beans fall onto a large cooling tray. A set of slowly rotating blades agitates the beans, causing them to cool quickly to stop the beans from continuing to roast. Once the beans cool, they are packaged into sealed bags and shipped to customers.

roasting degree

Knowing the roasting degree or color of coffee beans can help you determine the coffee flavor represented by a certain roasting degree to suit your personal preferences. But describing how roasted coffee beans are is a matter that can be controversial. There are many terms used to describe the degree of baking, including "city baking,""whole city baking,""French baking," and "Italian baking."

However, the meaning of these terms is ambiguous because they are defined differently in different countries and by different coffee companies. The use of these nouns is actually quite old-fashioned, but you can still see them on coffee bags in department stores. These terms are rare in specialty coffee roasters, but large chains such as Starbucks still find them marketable.

Since the degree of roasting chosen ultimately depends on individual taste, there is no "best" or "worst," just as some people prefer their steaks rare and some prefer them well-done. However, if you enter a world-class restaurant, you rely on the chef's expertise to bring out the best in each dish. Similarly, boutique coffee roasters pride themselves on knowing what level of roasting will give their beans the best flavor, and they do this by creating "roast curves." Rather than relying on vague colors or names, they describe each coffee bean by the distinctive flavor it brings.

For simplicity's sake, we've divided the baking levels into three categories: light, medium, and dark (remember that there are extensive subdivisions within each baking level). Most roast curves used for specialty coffee are in the light to medium roast range, where the roaster's intention is to highlight the inherent complexity of the coffee and carefully craft subtle flavors that reflect the growth and handling of the beans. When roasted, the coffee will have a natural sweetness and a balanced acidity, as well as different flavors such as fruit, chocolate and nuts. Medium to deep roast coffee beans are usually used to make espresso coffee because they are low in acidity and high in body, making them ideal for espresso. If roasted too long, the taste of the dark roast coffee will become less pleasant, and the original aroma of the coffee will become very small.