Detection of Maillard Reaction Products at Different Stages in Prepackaged Foods by Ultra-high Performance Liquid Chromatography-Stable Isotope Dilution Mass Spectrometry

A method was developed for the simultaneous determination of seven Maillard reaction products (MRPs), namely N^ε-(carboxymethyl)-lysine (CML), N^ε-(carboxyethyl)-lysine (CEL), methyglyoxal-derived hydroimidazolones (MG-H1, MG-H2 and MG-H3), glyoxal-derived hydroimidazolone (G-H1) and furosine in prepackaged foods by ultra-high performance liquid chromatography-triple quadrupole-tandem mass spectrometry (UPLC-QqQ-MS/MS). The chromatographic separation was performed on a Kinetex C₁₈ column and quantification was performed in the multiple reaction monitoring (MRM) mode. The recoveries of the method ranged from 88.4% to 111.3% with relative standard deviations (RSDs) less than 9% in terms of precision, and the limit of detection and the limit of quantification were 2.1–14.2 and 7.4–41.2 ng/mL, respectively. The developed method was applied to 134 typical prepackaged foods, and the obtained data was analyzed by principal component analysis (PCA) and correlation analysis (CA). The results showed that CML, MG-H1/3, MG-H2 and G-H1 were the major MRPs in prepackaged foods, and they had significant positive correlations with each other and with protein, fat and total sugar contents. This method shows acceptable linearity, accuracy and precision and is suitable for the rapid determination of multiple MRPs in prepackaged foods.