How many aroma compounds does coffee have?

By Norbert Ahnsorge (Inhaber) · Published · updated

Over 800 identified chemical compounds — making coffee one of the most aromatic foods in existence. Most of them are formed during roasting through the Maillard reaction and sugar degradation. Only a small portion of them is sensorially dominant.

What the research says

Coffee contains over 800 volatile aroma compounds — more than most other foods. This number comes from decades of analytical chemistry using gas chromatography. Every year, new compounds are identified.

However: Only about 30–40 of these compounds are sensorially relevant — meaning they occur in sufficient concentrations to actually influence the taste. The rest are present in too small quantities or have too high a perception threshold.

Where the aromas come from

The raw, green coffee bean smells like almost nothing — grassy, perhaps slightly pealike. The variety of aromas is created almost entirely during roasting through three chemical processes:

Maillard reaction: Amino acids and sugars react with each other and create hundreds of new compounds — responsible for nutty, caramel, and bread-like aromas.

Strecker degradation: A side branch of the Maillard reaction that releases aldehydes — responsible for malty, honey-like notes.

Caramelization: Sugars break down at high heat and create sweet, buttery, and slightly bitter compounds.

The longer and hotter the roast, the more roasted aromas (chocolate, smoke) dominate over origin aromas (fruit, flowers). This is why light roasts taste more complex and typical of their origin — the Maillard reaction is less advanced, and the bean's original characteristics are preserved.

In practice at Green Wall Coffee

At Sophienstraße 27 in Berlin-Lichtenberg, we don't roast ourselves, but I select our coffees deliberately — light roasts preserve the variety of aromas particularly well. A light Ethiopian natural can taste of blueberry, jasmine, and honey all at once. These are not fantasy descriptions on the bag, but measurable chemical compounds that you can actually taste with a little practice.

You'll find us at Sophienstraße 27 in Berlin-Lichtenberg, Monday to Friday 8am–5pm and Saturday 10am–5pm.

Further reading

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