The effect of stunning method (gas vs. electrical) on some breast meat quality traits was evaluated on 128 breasts (P. major muscles) of 106 day-old female BUT-Big6 turkeys (8.9 kg live wt) reared under intensive conditions. The birds were processed on a commercial processing plant using either electrical (E) or gas (G) stunning system. The birds from E group were shackled and electrically stunned with a constant voltage of 44V pulsating DC, 500Hz, for 22 sec (average of 18-20 mA/bird), while G group birds were stunned by CO2 exposure in their transport crates transiting through an underground chamber where birds encountered variable concentrations of carbon dioxide (from 10 to 60% CO2 going from the top to the bottom level, respectively) for 8 min and subsequently shackled (Linco® system). After stunning all turkeys were killed and processed following the same standard procedures. For both E and G group, 16 breasts were boned at 20 min, 6, 8 and 24 h post mortem (n = 128) and the incidence of blood-engorged wing veins and breast blood spots were evaluated. After boning, the samples were immediately analysed for muscle temperature (only 20 min post mortem), pH, R-value, and colour (L*a*b*), while at 24 h post mortem all collected samples were also analysed for pHu, drip loss, cooking yield and Allo-Kramer shear values of cooked meat. The gas stunning resulted in a lower incidence of blood-engorged wing veins (1.6 vs. 14.1%) and blood spots on breast meat (18.8 vs. 31.3%) as well as a lower redness (a*, 2.92 vs. 3.34; P<0.01) and yellowness (b*, 2.85 vs. 3.36; P<0.05). Furthermore, gas stunning produced a lower breast muscle temperature (38.0 vs. 40.2°C; P<0.01) and a higher pH value (6.07 vs. 6.00; P<0.05) at 20 min post mortem as well as a higher cooking yield (84.5 vs. 83.3%; P<0.01). No differences were found in pHu, R-value, lightness, drip loss and shear values according to the stunning method. However, considering the interaction between the stunning method and boning time, it was observed that when carcasses are boned at 6 h post mortem (commercial boning time), gas stunning produces lower shear values (2.55 vs. 3.35 kg/g; P<0.05) of cooked breast meat than electrical stunning. In conclusion, turkey breast meat from gas stunned birds seems to have more favourable quality characteristics in comparison to breast meat of electrical stunned birds.
BIANCHI M., PETRACCI M., CAVANI C. (2006). Gas stunning and quality characteristics of turkey breast meat. s.l : s.n.
Gas stunning and quality characteristics of turkey breast meat
BIANCHI, MAURIZIO;PETRACCI, MASSIMILIANO;CAVANI, CLAUDIO
2006
Abstract
The effect of stunning method (gas vs. electrical) on some breast meat quality traits was evaluated on 128 breasts (P. major muscles) of 106 day-old female BUT-Big6 turkeys (8.9 kg live wt) reared under intensive conditions. The birds were processed on a commercial processing plant using either electrical (E) or gas (G) stunning system. The birds from E group were shackled and electrically stunned with a constant voltage of 44V pulsating DC, 500Hz, for 22 sec (average of 18-20 mA/bird), while G group birds were stunned by CO2 exposure in their transport crates transiting through an underground chamber where birds encountered variable concentrations of carbon dioxide (from 10 to 60% CO2 going from the top to the bottom level, respectively) for 8 min and subsequently shackled (Linco® system). After stunning all turkeys were killed and processed following the same standard procedures. For both E and G group, 16 breasts were boned at 20 min, 6, 8 and 24 h post mortem (n = 128) and the incidence of blood-engorged wing veins and breast blood spots were evaluated. After boning, the samples were immediately analysed for muscle temperature (only 20 min post mortem), pH, R-value, and colour (L*a*b*), while at 24 h post mortem all collected samples were also analysed for pHu, drip loss, cooking yield and Allo-Kramer shear values of cooked meat. The gas stunning resulted in a lower incidence of blood-engorged wing veins (1.6 vs. 14.1%) and blood spots on breast meat (18.8 vs. 31.3%) as well as a lower redness (a*, 2.92 vs. 3.34; P<0.01) and yellowness (b*, 2.85 vs. 3.36; P<0.05). Furthermore, gas stunning produced a lower breast muscle temperature (38.0 vs. 40.2°C; P<0.01) and a higher pH value (6.07 vs. 6.00; P<0.05) at 20 min post mortem as well as a higher cooking yield (84.5 vs. 83.3%; P<0.01). No differences were found in pHu, R-value, lightness, drip loss and shear values according to the stunning method. However, considering the interaction between the stunning method and boning time, it was observed that when carcasses are boned at 6 h post mortem (commercial boning time), gas stunning produces lower shear values (2.55 vs. 3.35 kg/g; P<0.05) of cooked breast meat than electrical stunning. In conclusion, turkey breast meat from gas stunned birds seems to have more favourable quality characteristics in comparison to breast meat of electrical stunned birds.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
