Abstract
The aim of this study was to investigate the correlation of delta H-2 and delta C-13 of bulk milk powder and milk powder fatty acids to their production region. A total of 46 milk powder samples from across New Zealand were collected and analyzed. Principal component analysis (PCA) showed that the delta H-2 and delta C-13 of four fatty acids (C4:0, C14:0, C16:0, C18:1) and bulk milk powder were found to be correlated with regional production area. Linear discriminant analysis (LDA) models were prepared using different combinations of bulk and fatty acid delta H-2 and delta C-13. All models were effective in discriminating samples from the North and South Islands. The LDA model using just fatty acid delta H-2 and delta C-13 provided the best separation. Therefore, the isotopic composition of the aforementioned fatty acids can be utilized as a good biomarker in milk powder that conveys reliable isotopic information to track milk powders to their regional origin.