What is the primary component that contributes to coffee's aroma?

The primary component that contributes to coffee's aroma is indeed volatile compounds. These compounds are complex organic molecules that easily evaporate and carry the characteristic scents found in coffee. When coffee beans are roasted, a range of volatile aromatic compounds are released, giving rise to the rich and diverse aromas that people associate with coffee. These volatile compounds include various acids, aldehydes, esters, and phenols, which emerge through the roasting process and significantly influence the overall sensory experience of the coffee.

In contrast, while carbon dioxide does play a role in the freshness and preservation of coffee, it is not primarily responsible for aroma. Chlorogenic acids, present in coffee, certainly affect flavor and acidity but do not directly contribute to the coffee aroma itself. Fats and oils found in coffee can influence flavor and mouthfeel but are less significant in the overall aromatic profile compared to volatile compounds.