Metabolite profiles of normal and defective dry, firm and dark (DFD) meat extracts with known ultimate pH (pHu) values were determined by Orbitrap Tribrid ID-X untargeted analysis coupled to chemometrics. An intelligent MS3 AcquireXTM workflow firstly approached the unambiguous characterization of detected features that were subsequently quantified by a complementary MS1 study of biological replicates. Chemometric research revealed how threonylphenylalanine (overexpressed in normal meats) together to tetradecadienoyl- and hydroxydodecanoyl-carnitines (both overexpressed in DFD meats) appropriately grouped meat groups assayed. Robustness of such biomarkers was confirmed through a time-delayed study of a blind set of samples (unknown pHu) and evidenced limitations of pHu as an isolated parameter for accurate meat quality differentiation. Other acyl-carnitines also characterized DFD samples, suggesting interferences induced by pre-slaughter stress (PSS) on lipid catabolism that would explain accumulation of such intermediate metabolites. Results achieved can ease understanding of biochemical mechanisms underlying meat quality defects.
Keywords: Acyl-carnitine intermediates; Chemometric analysis; Iterative LC-MS(n) workflow; Meat quality biomarkers; Untargeted metabolomics; Validation assessment.
Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.