Low-voltage electrical stimulation effects on proteolysis and lamb tenderness

Lamb carcasses were subjected to low-voltage electrical stimulation (ES; 28 V, 60 Hz) within 5 min postmortem (PM), After ES, the longissimus thoracis (LT) and semimembranosus (SM) muscles were removed to investigate subsequent biochemical changes. The pH values of the ES muscles declined rapidly until the 1(st) 3 h PM (p < 0.05). The activities of mu-calpain and calpastatin in ES muscles decreased significantly after 10 h PM (p < 0.05), Both ES LT and SM muscles tended to have lower shear-force values, which suggested ES might accelerate activation of calpains as well as glycolytic rate, thereby improving muscle tenderness, Differences in titin and troponin-T degradation between treatments were also observed with time PM.