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

Department of Poultry Science, Texas A&M University, College Station 77843-2472, USA.

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 ES at the neck in a saline bath (570 V, 450 mA, AC, 60 Hz, 2 s on 1 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 higher R-values at 2 h postmortem when compared to control fillets. 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 ES and deboned at 2 h had significantly longer sarcomeres than the 2-h controls; however, there were no significant differences between the 2-h ES and the 8-h ES treatments, 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 ES system would not benefit turkey processors.