Using TD-GC-MS to analyze coffee beans aromas of different roast levels

An analytical methodology using Thermal Desorption (TD) and GC-MS was developed for the determination of components in coffee beans aromas. The purpose was to estimate the volatile compounds/components in coffee beans aromas of different roast levels, such as light, medium, medium-dark, and dark roast. Aromas samples were collected by using stainless steel tubes containing approximately 200 mg of Tenax TA adsorbents and sampling at a flow rate of 200 mL/min. Seventeen major components in coffee beans aromas were identified by the TD-GC-MS system. Results showed that most components increased with roast levels. However, furfurals had a different downward trend. Chemical reactions occurred during the roasting process were proposed to explain the decrease in furfurals: furfurals changed to 2-furanmethanol and 2-methylfuran.