Analysis of coffee bean with laser desorption ionization high-resolution mass spectrometry

This study evaluates the application of laser desorption ionization high-resolution mass spectrometry (LDI-HRMS) to identify coffee components. The coffee analysis was performed based on origins, roasting temperatures, and extraction methods. The LDI-HRMS experimental results were compared with electrospray ionization (ESI) HRMS analysis, which revealed major compositional differences of coffee ingredients between LDI and ESI data. It was also observed that bitter components in coffee increased with the increasing roasting temperature, and espresso was found to have more carbohydrate-derived compounds. This study clearly shows that coffee components can efficiently be identified with LDI. Moreover, a more systematic database can be constructed by combining it with LDI-imaging because LDI is simple, fast, and requires small amount sample consumption.