Muscle metabolism and meat quality of Pectoralis from turkeys treated with postmortem electrical stimulation

Abstract

This experiment was conducted to evaluate the effects of electrical stimulation (ES) on muscle metabolism and breast meat quality in turkeys. Thirty-six turkey hens were either electrically stimulated at the neck in a saline bath (570 V, 450 mA, AC, 60 Hz, 2 s on/ I s off for 10 pulses) or used as unstimulated controls. One breast fillet from all carcasses was harvested at 2 h postmortem. The opposite fillet was harvested from the ES carcasses at 8 h postmortem and from the unstimulated controls at either 8 or 24 h postmortem. All fillets were sampled at time of deboning for expressible moisture, pH, R-value, gravimetric fragmentation index (GFI), and sarcomere length. The remainder of the fillet and the samples for GFI and sarcomere length were aged on ice until 24 h postmortem. After aging fillets were analyzed for cook loss and shear value. Color was measured at time of deboning and at 24 h postmortem. Electrical stimulation accelerated rigor mortis development as indicated by significantly lower pH values and significantly higher R-values at 2 h postmortem. The pH and R-values of the 2 h ES treatment were not significantly different from the 8 h ES, 8 h controls or the 24 h controls. Fillets from carcasses that were electrically stimulated and deboned at 2 h had significantly longer sarcomeres compared to the 2 h controls; however, there were no significant differences between the 2 h ES treatment and the 8 h ES, 8 h controls or the 24 h controls. Although ES accelerated muscle metabolism at 2 h postmortem, it had no effect on shear value, expressible moisture, cook loss, GFI, L* or a* color values. These results suggest that this postmortem electrical stimulation system would not benefit turkey processors.