Potential of Fourier Transform Infrared Spectroscopy for Quantitative Analysis of β-Carotene in Refined, Bleached and Deodorised (RBD) Palm Olein

Abstract

Fourier transform infrared (FTIR) spectroscopy was used to determine β-carotene in refined,bleached and deodorised (RBD) palm olein. The method used sodium chloride windows with a 50 μmtransmission path. Fifty RBD palm olein samples spiked by known amount of standard (95%) β-caroteneto produce a wide range of concentration up to 2,000 ppm were used. The samples were separated intotwo groups for the calibration and validation. Partial least square (PLS) calibration models were employedfor predicting the β-carotene content in the FTIR spectral region. It was found that FTIR spectral regionsof 980-915 cm^-1 (trans =CH region) were the best for determining the β-carotene content with the lowestSEC (34.01) and SEP (47.19) and high R² values. The accuracy of the method was comparable to that ofthe high-performance liquid chromatography (HPLC). FTIR in conjunction with PLS has thus proved tobe a useful analytical tool for simple and rapid determination of β-carotene in RBD palm olein for routineanalysis.

Keywords : β-carotene / Fourier Transform Infrared Spectroscopy / Partial Least Square /Palm Olein