Novel approach for determination of milk fat adulteration with non-milk fat by RP-HPLC

Abstract

The present work studied the method for quickly determining milk fat adulteration with non-milk fat. The approach was based on analyzing characteristic fingerprints of triacylglycerols profile in combination with chemometric techniques and a multidimensional vector model. Nineteen fat samples of bovine milk, 20 samples of cow cheese, and ten samples of cow butter were analyzed by reverse-phase high-performance liquid chromatography. The areas of 3 triacylglycerol peaks with equivalent carbon numbers of 35.6, 46.2, and 47.2 were used for diagnosing chemometrics and building the vector model. It was shown that the proposed approach could be used to quickly determine milk fat adulteration by non-milk fat with a concentration from 1.5 to 100%. Application of the vector model to 20 samples of cow cheese showed that most of them were made of authentic cow milk; however, the milk fat in 7 of these samples had been replaced with non-milk fat. For ten samples of cow butter, only three samples were produced from milk fat alone, while for other samples, the mass fraction of non-milk fat, expressed as palm oil, was determined to be in the range of 10–90%.