Peptide biomarkers identified by LC–MS in processed meats of five animal species

The purpose of this study was to find heat-stable peptide biomarkers in cooked meats of five animal species: pork, chicken, duck, beef, and sheep. First, whole proteins and peptides were analyzed and identified by LC–MS to find homologous proteins and potential peptide biomarkers in the five different raw meats. Next, the peptide biomarkers of the raw and cooked meats were confirmed by multiple reaction monitoring (MRM). Thirty-four peptide biomarkers and twenty heat-stable peptide biomarkers were confirmed for the raw meats and the cooked meats, respectively. Eighteen of the heat-stable peptide biomarkers were not previously reported. Peptide biomarkers verified by MRM permit identification of each species with high specificity and selectivity to provide reliable results for meat authenticity after grilling and instant-boiling. Some of the biomarkers are species-specific only among the above five species.