Simultaneous quantitative analysis of red fruit oil and sesame oil using FTIR spectroscopy and multivariate calibrations

Sesame oil (SeO) and red fruit oil (RFO) share several similarities, especially in color properties. Both SeO and RFO are red in color. The objective of this study was to analyze SeO and RFO simultaneously using FTIR spectroscopy and multivariate calibrations of partial least square and principle component regressions. Some frequency regions and spectral treatments were optimized. The selection of the spectral treatment, frequency region and multivariate calibrations types was based on the ability to provide the highest values of coefficient of determination (R²) and the lowest values of errors, either in calibration or prediction. Based on these criteria, FTIR spectra using normal mode and partial least square, regression at frequency regions of 1200 – 1000 cm^-1 was suitable for determination of SeO and RFO simultaneously. The developed method is rapid at one minute per sample, sensitive, and considered as a green analytical technique since the use of chemicals and reagents are minimized.