Chemometric determination of the geographical origin of cow milk using ICP-OES data and isotopic ratios: A preliminary study

The geographical origin of twenty cow milk samples from two different geographical areas of the Apulia region in southern Italy was determined using Inductively Coupled Plasma Emission Spectroscopy (ICP-OES) for the metals (Ba, Mn, Zn, Al, Fe and Cu), and isotope ratio mass spectrometry (IRMS). The phosphorous concentration was determined by colorimetry. The data were processed using the following multivariate statistical methods: Principal Components Analysis (PCA), Hierarchical Clustering (HCA) and Linear Discriminant Analysis (LDA). The samples were divided into two groups according to their origin and were classified by discriminant analysis which gave 100% success. This method could be extended to classify dairy products like mozzarella and cheese in order to verify and safeguard Protected Designation of Origin (PDO) products.