Elucidating the Origin of Milk Products on the Chinese Market Using Hydrogen and Oxygen Stable Isotope Technique

Abstract

Preference for foreign milk products is the cause of the economically motivated adulteration of milk products on the Chinese market. 42 milk samples from the United States of America, Canada, Southern China, Northern China, Australia and New Zealand were analyzed using δ2H and δ18O stable isotope technique to differentiate the origin of milk products. An isotope ratio mass spectrometer with a combination of a high-temperature conversion elemental analyzer, Thermo-Fisher was used. Statistical analysis was performed using one-way ANOVA. The study revealed δ2H and δ18O had a wide range of mean values: 13.86 to 22.25‰ and -82.86 to -28.5‰, respectively. There was a significant difference in the δ2H (n=7; F=20880, P=7.876E-43) and δ18O (n=7; F=1399.0; P=9.215E-29) composition of the milk samples from the different regions. It was observed that δ2H and δ18O composition is helpful in elucidating milk products from different regions on the Chinese market (P<0.05).