Analysis of sunflower oil in ternary mixture with grapeseed oil and candlenut oil in the ternary mixture system using ftir spectroscopy and chemometrics

Candlenut oil (CDNO) has a high price in the market so that it can be adulterated with one or more oils, therefore, the authentication of CDNO is very important. This study was aimed to develop a Fourier transform infrared (FTIR) spectroscopy combined with chemometrics to analyze sunflower oil (SFO) in ternary mixture with grapeseed oil (GPO) and CDNO. SFO, GPO, CDNO and its ternary mixture were prepared and scanned randomly using FTIR spectrophotometer in the mid-infrared region of 4000-650 cm^-1, 8 cm^-1 resolution and thirty-two scans. SFO quantification was performed using two multivariate calibrations of principle component regression (PCR) and partial least square (PLS). PLS using the second derivative FTIR-ATR spectra at wavenumbers regions of 3100-2750 cm^-1 was used for quantitative analysis of SFO in ternary mixtures with GPO and CDNO, with correlation coefficient (R) values obtained for the relationship between actual values and FTIR predicted values of SFO of 0.9999 and 0.8744 in calibration and validation models, respectively. The errors in calibration and prediction models, expressed by the root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP), were low, i.e. 0.233 and 7.90, respectively. The use of FTIR spectroscopy method combined with multivariate calibration techniques is an appropriate method for detecting the adulteration of candlenut oil from GPO and SFO. © 2020 Elsevier B.V., All rights reserved.