A New Method for Determining β-Carotene in Refined, Bleached and Deodorized Palm Olein by Fourier Transform Infrared Spectroscopy

Abstract: A new method for the determination of β-carotene using Fourier Transform Infrared (FTIR) spectroscopy in refined bleached and deodorized (RBD) palm olein was developed. RBD palm olein was pre-analyzed for β-carotene by high performance liquid chromatography (HPLC) method. The calibration samples were prepared by spiking known amount of β-carotene to produce a wide range of β-carotene up to 2000 ppm. The method was based on the sodium chloride (NaCl) windows, and the transmission path was fixed at 50 µm at room temperature. The partial least squares (PLS) calibration models for predicting β-carotene was developed by using the FTIR spectral region at 980-915 cm^-1 that is associated with trans double bond CH absorption. The accuracy of the method was comparable to that of ultraviolet (UV) visible method with a coefficients of determination (R2) of 0.9950 and standard error of calibration (SEC) of 19.47. The standard deviation of difference for repeatability (SDDr) for the method was comparable to that for UV-visible method. The new FTIR method developed was shown to be efficient, accurate and suitable for routine quality control analysis with results obtainable in about 2 min.