FTIR Spectroscopic and Multivariate Analysis for Sample Discrimination and Adulteration Detection of Ulin Seed (Eusideroxylon Zwageri Teijsm. & Binn.) Oil

This study investigates the optimal characteristics of ulin seeds for oil extraction and the detection of adulteration in ulin seed oil (USO) using FTIR spectrophotometry and principal component analysis (PCA). The research found that fresh, mature, and resinous ulin seeds are ideal for oil extraction. Adulteration with candlenut oil and virgin coconut oil can be detected at specific wavenumbers, particularly 3008, 1745, and 1118 cm⁻¹. The PCA analysis highlighted the wavenumber 1745 cm⁻¹ as a key indicator for identifying USO adulteration.