My dad isn’t that into coffee, a concept that mystified me until I learned he had lost most of his sense of smell. Suddenly, it all made sense because when it comes to coffee, the aroma is as essential a part of the experience as the taste.
Here we’ll talk about coffee aroma’s scientific basis, its importance in enjoying coffee, and how you can describe it like a coffee pro.
Aroma, Taste, And Flavor
The terms aroma, taste, and flavor are too often used interchangeably, but they refer to different ways of experiencing coffee. Before we dig deeper into learning things about the aroma of coffee, let’s clarify:
- An aroma is an odor sensed in the nose and at the back of the mouth. More than any other sense, the aroma is linked to memories and emotions.
- A taste is a sense experienced by the tongue.
- A flavor is a holistic term encompassing both taste and aroma. Coffee flavor notes describe the complete experience of drinking.
Where Does Coffee Aroma Come From?
Green coffee beans have a minimal aroma; you must roast them to create and release the volatile compounds our nose can detect. The Maillard Reaction between amino acids and sugar is responsible for much of coffee’s flavor. This reaction occurs at high heat and produces the flavor of many browned foods.
Beware that creating aromas through roasting isn’t always a good thing. For example, roasting for too long forms phenols like guaiacol, which has ashy aromas (1).
Grinding coffee increases its aroma by increasing the surface area of the coffee to release more aromatic compounds.
Brewing coffee produces even more aroma, as the hot water extracts different chemicals. That’s why a cup of coffee may not smell the same as the ground coffee produced.
Coffee beans contain more than 800 aromatic compounds, even more than wine (2). But our sense organs can only detect about 30 of them. Just imagine how your morning java must smell to your dog!
How To Describe Coffee Smells
Describing a smell is challenging, but coffee experts have a trick up their sleeve. They rely on the Coffee Taster’s Flavor Wheel for guidance on descriptive words for coffee.
This is the largest and most collaborative piece of research on coffee flavor ever completed, inspiring a new set of vocabulary for industry professionals.
It categorizes dozens of tastes and aromas to describe a coffee. For example, the aromas of lighter roasts are often noted as fruity, flowery, or herbaceous. Medium roasted coffee beans can be caramelized, nutty, spicy, or chocolaty, and dark roasts have bold aroma descriptors like smoky and earthy.
This video from James Hoffmann provides an excellent introduction to coffee tasting: