Coffee flavor is the result of all the taste sensations from the aroma to the final aftertaste. There are many factors that can influence the perception of coffee flavor, including the temperature of the beverage. The main flavor descriptor can change as the coffee cools.
Coffee beans and roasted coffee contain more than 800 different chemical compounds that can affect their flavor and aroma. Among these, the most important molecules that determine coffee flavor are carbonyls, phenols, esters, and pyrazines. But you don’t need expensive equipment or a Ph.D. in chemistry to start understanding coffee flavor. It’s enough to know which characteristics to look for. We will discuss the most important ones: aroma, sweetness, acidity, bitterness, and aftertaste.
When it comes to taste, the sense of smell plays an important role. In fact, most researchers agree that it’s the sense of smell that has the greatest impact on how we perceive flavor.
The neurons responsible for our sense of smell, known as olfactory neurons, are responsible for much of the sensation we experience when we eat or drink. When we breathe in air, odor molecules bind to these neurons, which then send signals to the brain about what we’re smelling. If we have a stuffy nose, it can interfere with our sense of smell and reduce our ability to fully perceive taste.
Olfactory receptor neurons are located in a small area at the top of the nasal cavity / Source: bio.libretexts.org
The different chemical compounds found in coffee play an important role in creating its unique flavor. Pyrazines contribute to grassy and earthy notes, while pyridinines are responsible for fruity and floral notes. Lipids and oils can give coffee a nutty or chocolatey flavor.
The origin of the coffee beans, such as the country and region where they are grown, the coffee variety, the growing conditions, the processing method (wet or dry), the degree of roasting, and the preparation methods can all have a significant impact on the coffee aroma, which can vary widely.
Many people describe the taste of coffee with words like caramel or chocolate, which are typically associated with sweetness. However, coffee itself is not naturally sweet. Rather, it is the roasting process that gives coffee its unique sweet taste. In addition, the higher density of the coffee beans intensifies this sensation. Understanding the sweetness of coffee can help you better appreciate and evaluate the overall balance of flavors in the beverage.
The process of roasting coffee beans involves high temperatures that cause the sugars in the beans to break down or change into other compounds. As a result, the sugar content of roasted coffee beans is significantly reduced compared to unroasted beans. As a result, the final beverage contains even less sugar.
Acidity is an important factor in coffee that adds freshness to the beverage. It also affects the perception of its texture. The taste of coffee can be described with words such as juicy, fruity or berry, due to the presence of different acids. However, it is important to consider the balance of these acids with other flavor characteristics such as bitterness or sweetness.
Roasted coffee is made up of different acids that contribute to its flavor. However, these acids are balanced by other flavor elements in the coffee, resulting in a smooth taste. For example, bitterness can balance acidity, creating a complex and well-rounded flavor profile.
Coffees that are known for their high acidity are usually grown at high altitudes in shaded areas. Nonetheless, altitude has not been found to have a significant impact on the acidity of coffees grown in non-shaded areas. Some growers, such as those from Kenya and Colombia, are renowned for producing coffees that have vibrant flavors and pronounced acidity.
Coffees known for their high acidity are usually grown at high altitudes in shaded areas. However, altitude has not been found to have a significant effect on the acidity of coffees grown in non-shaded areas. Some growers, such as those in Kenya and Colombia, are known for producing coffees with vibrant flavors and pronounced acidity.
The Impact of Altitude on the Biochemical Composition and Quality of Green Arabica Coffee Beans / sciencedirect.com
During the roasting process, coffee beans undergo several chemical changes that significantly alter their acidity. These changes are the result of caramelization and the breakdown of organic acids. Initially, green coffee beans have a high acidity level, typically around pH 5.8. However, as the beans are roasted, the acidity decreases. The first critical point in coffee roasting is called the “first crack,” which occurs at a temperature of about 205-210 degrees Celsius. At the end of the first crack, the acidity is usually reduced to pH 4.8.
It is common for people to attribute any flaw in a beverage to its bitterness. For example, when people taste an unpleasant coffee, they often say that it is too bitter. However, this response may not be entirely accurate, because the taste sensation that people generally refer to as bitterness is often actually sourness or acidity. In the case of espresso-based drinks, the bitterness may be due to improperly whipped milk.
Bitterness in coffee is caused by the complex interaction of several chemical compounds present in coffee beans that are formed during roasting. Trigonelline, cinnamic acid and caffeine, once thought to be tasteless, are primarily responsible for the bitterness in coffee.
In coffee, bitterness can actually enhance sweetness and balance unwanted acidity. It serves to structure the flavor profile, bringing all the different elements together into a harmonious whole.
However, a bitter taste in coffee is often an indication of over-extraction. This means that if you extract too much from your espresso or brew your French press for too long, you’ll end up with a batch of bitter coffee. On the other hand, if you extract too little, you’ll get a less bitter version.
The taste sensation that remains in your mouth after you’ve finished drinking coffee is known as the coffee aftertaste. This aftertaste can vary in length and can remain in your mouth for several minutes or even longer.
Coffee aftertaste is made up of different flavors that can be similar to the taste of the coffee itself. These may include fruity, citrus, nutty, chocolate, or caramel flavors.
In addition to taste, the coffee aftertaste can be accompanied by other sensations such as astringency, warmth or coolness, which can contribute to the overall experience of the beverage.
Understanding coffee taste can help you make the perfect cup of coffee to suit your preferences. You can adjust the grind, the brewing method, and the ratio of coffee to water. Knowing your preferred coffee taste will help you choose the right water and coffee beans.
Moreover, for many people, coffee is not only a beverage, but also a topic of discussion and socialization. In addition to cupping, which is often participated in by professionals and amateurs alike, many countries hold championships where participants describe the taste of coffee in detail.