Profiles of sulfur containing compounds obtained from Arabica and Robusta coffees by capillary column gas chromatography

Abstract

The profiles of sulfur containing compounds present in both Arabica and Robusta coffees were determined by concentrating the volatiles from dry ground roasted coffee headspace, pressed coffee oil or brewed coffee headspace onto an adsorbent (Tenax) which was then thermally desorbed into a capillary column. The volatiles were then chromatographed and detected with a flame photometric detector. Significant quantitative differences between the profiles of Arabica coffee and Robusta coffee are found for all three sample types with a few components being up to 20-times more concentrated in the Robusta coffee than in the Arabica coffee. These differences may be utilized to detect as little as 1 % Robusta coffee present in Arabica coffee.