Discrimination of Rice Varieties using Laser-Induced Breakdown Spectroscopy assisted with Principal Component Analysis (PCA)

This research employed laser-induced breakdown spectroscopy (LIBS) technique to analyse elements in various rice samples including white rice, fragrant rice, basmati rice, and glutinous rice. The LIBS parameters including laser energy and integration time were optimised to obtain the optimised LIBS spectra ranging from 30 40, and 50 mJ and 10, 20, and 30 ms, respectively. The optimised LIBS parameters used in this study were determined at 40 mJ laser energy and 20 ms integration time. From the obtained LIBS spectrum, the elemental composition in rice were identified using National Institute of Standards and Technology (NIST) database. Principal component analysis (PCA), was used for further analysis to discriminate between each type of rice. The results from the PCA score were able to discriminate white and fragrant rice. However, for basmati and glutinous rice, the data points were overlapping with each other.