Effect of EU electrical stunning conditions on breast meat quality of broiler chickens

Electrical stunning is still the main method used worldwide in commercial poultry plants. The stunning procedures in water bath affect both bird welfare and meat quality attributes. The European Union (EU) Council Regulation 1099/2009 on the protection of the animal at the time of killing established the minimum current flow through individual bird at a specified frequency to assure an effective stun that must last until the bird death. The aim of this study was to compare the effect of the application of different stunning current flows on the incidence of hemorrhages (classified as 1=no lesion, 2=moderate and 3=severe lesion) and some quality traits (pHu, color, drip and cooking losses, and shear force) of chicken breast meat. A total of 12 flocks of broiler chickens, each equally divided into light, medium and heavy-size, were submitted either to the stunning condition usually adopted before the entry into force of the current EU Regulation (90 mA/bird, 400 Hz) (OLD) or to that enforced by it (150 mA/bird, 400 Hz) (NEW). Overall, the incidence of severe hemorrhages dramatically increased in NEW group in comparison with OLD one (55 vs. 27%; P<0.001) and particularly in heavy-size birds (72 vs. 25%; P<0.001). In general, meat quality attributes were not affected by the stunning conditions with the exception of drip loss that resulted lower in NEW than OLD birds (1.01 vs. 1.27; P<0.001). In conclusion, the adoption of a higher current flow, as suggested by the EU regulation to protect animal at the time of killing, increases the incidence of breast hemorrhages while maintaining meat quality traits with possible beneficial effect on water holding capacity of fresh meat.