Altered post-mortem metabolism identified in very fast chilled lamb M. longissimus thoracis et lumborum using metabolomic analysis

•Very fast chilling (VFC) was defined as muscle temperature below 0 °C early pre-rigor.•Metabolomics was used to investigate changes in lamb muscles subjected to VFC.•Muscles subjected to VFC had higher glycolytic intermediates pre-rigor.•VFC muscles had more end-products of nucleotide metabolism pre-rigor.•VFC caused considerable changes in metabolism and rigor onset, which were associated with tender meat.

The aim of this experiment was to use metabolomic techniques to investigate the energy metabolism in lamb M. longissimus thoracis et lumborum subjected to very fast chilling (VFC) post-mortem. The tissue was prepared by 2 different operators and subjected to very fast chilling (less than 0 °C within 1.5 h of slaughter) or typical chilling regimes (Control; 0 °C within 22 h of slaughter). Non-targeted metabolomic analysis (1H NMR) and targeted analysis (31P NMR, HPLC-PDA and HPLC-MS/MS) were used to examine the change in muscle metabolites post-mortem. One VFC treatment, which resulted in a colder core temperature and more tender meat, had higher levels of glycolytic intermediate metabolites pre-rigor as well as more of the end-products of adenosine and nicotine nucleotide metabolism pre-rigor, relative to conventionally chilled treatments. In conclusion, VFC to less than 0 °C within 1.5 h of slaughter causes considerable changes in metabolism and rigor onset, which are associated with tender meat.