Fingerprinting of yogurt products by laser desorption spray post‐ionization mass spectrometry

Yogurt and related products have been directly analyzed using laser desorption spray post-ionization mass spectrometry (LDSPI-MS) in positive ion mode. Assignments are made for some of the abundant diagnostic peaks through LDSPI-MS/MS analysis in comparison with authentic compounds. It is demonstrated that different yogurt products can be reliably differentiated according to their LDSPI-MS spectra. Principal component analysis (PCA) is further used to clearly show the capability of LDSPI-MS fingerprinting for rapid sorting of yogurt products. We believe that this sample-preparation-free technique can be a very useful product screening tool in the dairy industry because of its simplicity, reliability and high throughput.