Electrical Water Bath Stunning of Broilers: Effects on Breast Meat Quality

Abstract

The objective of this study was to investigate the influence of electrical water bath stunning treatments (pulsed direct current) on stress conditions of poultry meat. This was carried out by evaluating meat quality measured through the incidence of PSE (pale, soft, exudative) in broiler breast fillet meat. We applied the randomized factorial design 2² with three replications at the central point, with independent variables, including voltage (40, 80, 120 V) and electrical frequency (100, 400, 700 Hz). The response functions under study were pH, L*, a*, b*, WHC and incidence of PSE meat. Samples presenting with pH of ≤5.80 and L* of ≥53.0 were classified as PSE whereas those with 5.80<pH<6.00 and 44.0<L*<53.0 were considered normal. The fillets taken from birds without stunning presented 54.14% of PSE meat samples, which decreased to 25.0% with stunning. The response functions L* and incidence of PSE showed regression (P≤0.05) with good adjustment of experimental data to the proposed model. The lowest incidence of PSE meat was observed when voltage and frequency were at their highest levels. In poultry slaughter, the applied electric stunning voltage of 120 V with a frequency of 700 Hz was determined to be the most effective for inhibition of PSE development.