Application of FTIR Spectroscopy for Assessment of Green Coffee Beans According to Their Origin

Samples of green coffee beans originating from five different countries were ground and analyzed using FTIR spectra in the region of 600-4000 cm(-1). Successful discrimination of each coffee type based on their origin was achieved applying a PCA algorithm on the obtained IR spectra for all samples. PCA loading plots show that the IR bands at 2850, 2920, and 1745 cm(-1) corresponding to the symmetric, and antisymmetric vibrations of CH2 and the stretching vibration of C=O bond in ester, respectively, are the most significant peaks in distinguishing the origin of the above coffee samples.