Fragmentation and Tenderness in Breast Muscle from Broiler Carcasses Treated with Electrical Stimulation and High-Temperature Conditioning

In each of four replications, broiler carcasses were treated with electrical stimulation (ES) (100 V, 1 A, 1 s on and 1 s off, 14 min) and high-temperature conditioning (HTC) in a 39 C water bath or conventionally processed and chilled. After harvesting at 1 h post-mortem, Pectoralis fillets were aged 23 h more and evaluated for cooked meat shear value. Pectoralis samples also were collected at 1 h post-mortem, aged for 0 or 23 h more, and analyzed for gravimetric fragmentation index using room air or an oven for drying the residue-laden screens. The results suggested that the ES and HTC treatments prevented myofibrillar fragmentation that occurred in the control carcasses. Also, although fragmentation index and shear value were correlated within the combined ES and HTC treatments, these two parameters were not correlated when the data from all treatment combinations were combined. Oven drying improved both the ability of the fragmentation index measurement to resolve differences between treatment means and to evaluate the correlation between this parameter and shear value. Sample aging time was observed to have little effect on the relative differences between treatment means but improved the correlation between fragmentation index and shear value.