Adulteration detection of Qinghai-Tibet Plateau flaxseed oil using HPLC-ELSD profiling of triacylglycerols and chemometrics

Abstract

The purpose of this study was to develop a hierarchical approach by combining similarity evaluation (SE), discriminant analysis (DA) and principal component analysis (PCA) to detect the adulteration of Qinghai-Tibet Plateau flaxseed oil using triacylglycerol (TAG) profiles with HPLC-ELSD. SE could effectively differentiate pure flaxseed oil from non-flaxseed oil when the adulteration concentration of six vegetable oils was greater than 10%. In TAG discriminant analysis, there was 100% accuracy in detecting adulteration by rapeseed, corn, peanut, soybean, and sesame oils in flaxseed oil when the adulteration concentration was greater than 10%, while the accuracy of detecting sunflower oil in flaxseed oil was 98.75%. PCA detected the adulteration of flaxseed oil by rapeseed, corn, peanut, sunflower seed, soybean, and sesame oils with an accuracy of 100% when TAG was used as an indicator. The comparative results showed that TAG was more effective in identifying the types and specific concentrations of adulteration of the six vegetable oils in flaxseed oil than equivalent carbon numbers (ECN), indicating that the TAG approach is a valuable tool to detect and quantify the adulteration of Qinghai-Tibet Plateau flaxseed oil.