Detection of the adulteration of water buffalo milk and mozzarella with cow’s milk by liquid chromatography–mass spectrometry analysis of β-lactoglobulin variants

A liquid chromatography–mass spectrometry method for detecting a fraudulent addition of cow’s milk to water buffalo milk and mozzarella is described. The presented approach utilises the whey protein β-lactoglobulin as marker for an adulteration. It offers a rapid determination combined with unequivocal identification of the marker protein in every run. An in-depth discussion of the subsequent data analysis highlights the potential problems of obtaining quantitative information on the level of adulteration. In an examination of 18 commercial buffalo mozzarella samples three products were found to be adulterated with high levels of cow’s milk.