Volatile compounds profiles in unroasted Coffea arabica and Coffea canephora beans from different countries

Abstract

Aroma is the most important factor in assessing the quality of coffee. The volatile compounds profile could be very important to confirm the authenticity of Coffea arabica. The study was carried out on two species of unroasted coffee beans: Coffea arabica from Colombia and Nepal and Coffea robusta from Uganda and Vietnam. Both Coffea arabica and Coffea canephora were imported to the country of analysis approximately 5 months prior to the research. Before the analysis, the coffee beans were kept in a sealed, dark container, at 21 °C. The tests were performed using an electronic nose. Its functioning is based on gas chromatography with two columns of different polarities in parallel and with 2 ultra sensitive Flame Ionization Detectors (FID). With multivariate statistics – Principal Components Analysis – it was possible to reduce the number of links and present them in two dimensions, which allowed for the unambiguous identification and assignment of samples to a particular species of coffee. By using an electronic nose, one can distinguish and group unroasted coffee beans’ flavours depending on the country of origin and species.