Molecular mechanism of protein dynamic change for Hengshan goat meat during freezing storage based on high-throughput proteomics

As traditional frozen storage leads to the degradation of meat quality, elucidation of dynamic change mechanism is urgently needed. Proteomic differences in postmortem frozen storage time (0, 30 and 60 days) of Hengshan goat meat at 18 degrees C were studied by label-free proteomics based on high resolution quadrupole-Orbitrap mass spectrometry. A total of 492 proteins were identified, of which 485 proteins were quantified, and the difference of 199 proteins was observed. The analysis of the differentially expressed proteins related to quality observed that triosephosphate isomerase and peroxiredoxin-6 were potential biomarkers for goat meat discoloration. Troponin and myosin can represent the tenderness of goat meat. Heat shock protein 70 can be used as water-retaining proteins in goat meat. Bioinformatics analysis suggested that the distinguishingly expressed proteins were involved in glycolysis and the ubiquitin-proteasome pathway revealing that the strong degradation of proteins, which cause of the degradation of long-term frozen meat quality. These results could enrich and beyond the existing knowledge of frozen meat, expecting to have a further understanding of the changes of meat quality at the molecular level.