Sample preparation

Three porcine muscles, longissimus lumborum (LL), psoas major (PM), and infra spinam (IS), were excised from carcasses of eight crossbred (Landrace×Yorkshire×Duroc), castrated male pigs. The average live weight of these pigs was 110.5±2.62 kg. Pigs were slaughtered by electrical stunning. Approximately 10±0.5 g of each muscle was taken and frozen in isopentane liquid nitrogen for histochemical analysis within 45 min postmortem. These samples were then stored at –80℃ until subsequent analyses. Meat quality were carried out after 36 h postmortem. For content of nucleotides and electronic taste-traits analysis, the analyses were performed after completing meat quality analysis. Three repetition were conducted and all measurements were made at 48 h postmortem.