Coffee aroma and flavor determine about 80% of the quality of a roast coffee beverage. Generally, most of the aroma compounds are generated at medium roast. Aroma formed during the roasting process normally at 210 °C for 6-10 minutes.
The coffee oil, which comprises about 10% of the roast beans carries most of the coffee aroma. More than 800 volatile compounds have been found in roasted coffee.
Many of the aromatic components of roasted coffee and particularly of coffee oil itself, are extremely susceptible to deterioration by the action of moisture and oxygen.
The staleness of coffee is due to the oxidative changes that take place with certain coffee constituents. This is prevented by the presence of carbon dioxide in roasted coffee. However, on storage, carbon dioxide is lost and so are the flavor and aroma.
In commercial practice, therefore roasted coffee has to be packed in an atmosphere of low oxygen content, either by CO2 gas-flushing or vacuum packing.
Coffee aroma
