Post mortem evolution of myofilament spacing and extracellular space in veal muscle

Abstract

The post mortem evolution of water distribution was studied in muscle tissue from veal calves in two experiments. Myofilament spacing, extracellular space and rate and extent of pH fall were determined in Psoas major muscle in Experiment 1. Extracellular space and rate and extent of pH fall were determined in Longissimus dorsi, Psoas major and Trapezius muscles in Experiment 2. In Experiment 2, the variability of ultimate pH was increased by using adrenalin injections. The myofilament spacing decreased after slaughter when pH reached values around 5·9. In both experiments, the extracellular space began to increase soon after slaughter in close relation with the pH changes. The size of the ultimate extracellular space was significantly correlated with the rate of pH fall, but not with the ultimate pH.