Supply chain models dictate pork spoilage rates: Metabolomic profiling reveals the degradation mechanism under ambient exposure.

Cold chain logistics is vital for maintaining the quality of livestock products. This study applied untargeted metabolomics to investigate the influence of various supply chain models on pork quality and metabolic profiles under ambient temperature conditions. Fresh pork samples from four simulated circulation modes-constant temperature (CK), farmer's market (FM), dealer (DG), and direct sales (DS)-were analyzed over storage periods, focusing on short-term spoilage dynamics. Results demonstrated accelerated biochemical deterioration under simulated conditions, marked by elevated pH, TVB-N, and TVC levels. Comparative analysis of the four circulation models against the control (CK-0d) identified 177 common differential metabolites exhibiting significant alterations. Key metabolic pathways engaged in spoilage involved amino acid, nucleotide, and vitamin metabolism, with a distinct focus on vitamin B6 and purine pathways. The DS model exhibited delayed spoilage, whereas the FM model showed rapid decomposition, attributed to the DS reduced exposure time to ambient temperature, which lowered the rate of degradation. Metabolomic profiling disclosed pivotal biomarkers such as putrescine and hypoxanthine, shedding light on the molecular mechanisms of pork spoilage. These findings underscore the necessity of cold chain integrity and provide metabolic insights for optimizing supply chain practices to enhance meat safety.