Mid-infrared spectroscopic detection of sunflower oil adulteration with safflower oil

• Main Authors: O. Uncu, B. Ozen, F. Tokatli
• Format: Article
• Language: English
• Published: Consejo Superior de Investigaciones Científicas 2019-03-01
• Series: Grasas y Aceites
• Subjects: adulteration; chemometrics; mid-infrared spectroscopy; safflower oil; sunflower oil
• Online Access: http://grasasyaceites.revistas.csic.es/index.php/grasasyaceites/article/view/1758

The oil industry is in need of rapid analysis techniques to differentiate mixtures of safflower-sunflower oils from pure oils. The current adulteration detection methods are generally cumbersome and detection limits are questionable. The aim of this study was to test the capability of a mid-infrared spectroscopic method to detect the adulteration of sunflower oil with safflower oil compared to fatty acid analysis. Mid-infrared spectra of pure oils and their mixtures at the 10–60% range were obtained at 4000–650 cm-1 wavenumber and fatty acid profiles were determined. Data were analyzed by multivariate statistical analysis techniques. The lowest level of detection was obtained with mid-infrared spectroscopy at 30% while the fatty acid profile could determine adulteration at around 60%. Adulteration levels were predicted successfully using PLS regression analysis of infrared data with R2 (calibration) = 0.96 and R2 (validation) = 0.93. As a rapid and minimum waste generating technique, mid-infrared spectroscopy could be a useful tool for the screening of raw material to detect safflower-sunflower oil mixtures.