Electrical Stunning, Hot Boning, and Quality of Chicken Breast Meat

Abstract

The first experiment was conducted to determine the effects of varying voltage, 20, 40, 80, and 100 V at 60 Hz, on stunning efficiency, blood loss, and carcass defects. In the second experiment, the same parameters were evaluated to determine the effects of varying frequency, 60, 200, 350, 500, and 1,000 Hz at 40 V. A control group for both experiments was not stunned. At 40V, 30 to 50 mA, 90% of the birds were unconscious, as shown by no response to comb piercing, and blood loss was maximized (55.3%). When varying the stunning frequency, maximum blood loss (73.1%), 90% of the birds were unconscious, and minimum carcass defects were observed at 1,000 Hz, 40 V. In the third experiment, birds were stunned at 40 V, 1,000 Hz and deboned immediately after defeathering (hot boning) and chilled or deboned after passing through all stages of a commercial abattoir operation (conventional boning). Control lots were unstunned and followed normal abattoir stages. Average shear value was significantly lower for stunned compared to unstunned birds (6.0 vs. 7.1 kg/g), although tenderness scores, as measured by a trained panel, were not significantly different (6.6 for stunned birds vs. 6.1 for unstunned). Scores for juiciness were also not significantly different (5.5 for stunned vs. 5.8 for unstunned). Average shear value was also significantly lower for conventionally boned birds (5.2 kg/g) than for hot boned birds (7.9 kg/g). Sensory analysis confirmed the shear value results. Conventionally boned breasts had an average tenderness score of 7.4 vs. an average of 5.3 for hot boned breast. No statistical differences were observed with respect to juiciness, although a score of 6.2 was observed for conventionally boned breast meat vs. a score of 5.1 for hot boned breast meat.

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

“…In fact, less blood loss was observed in carcasses from WoS chickens in relation to WtS under at 20, 40, 80, and 100 V with a frequency of 60 Hz and also varying the frequency of 60, 200, 350, 500 and 1000 Hz at a constant voltage of 40 V (Contreras and Beraquet, 2001). In contrast, stunning the animal by any method produces a rise in blood pressure in the arteries, capillaries, and veins and causing a transient increase in heart rate, which are all factors that favor successful bleeding (Thornton, 1969).…”

“…These stressful conditions accelerate the onset of rigor mortis, which would be avoided by the use of proper use of electrical stunning methodologies (Ma and Adis, 1973;. Contreras and Beraquet (2001) studied the effect of various voltages (20,40,80 and 100 V at 60 Hz and no stunning) and frequencies (60,200,350,500 and 1000 Hz at 40 V) on the efficiency of stunning, blood loss and defects in chicken carcass. At a current of 40 V and frequency of 1000 Hz, they observed that 90% of animals were stunned and blood loss was maximized.…”

Identification of troponin I and actin, alpha cardiac muscle 1 as potential biomarkers for hearts of electrically stimulated chickens

“…According to Gregory and co-workers [10], 99 % of the birds show ventricular fibrillation with currents greater than 110 mA at 50 Hz. Contreras and Beraquet [11] reported that in a range of 20 to 125 mA, only birds stunned at 100 V, 60 Hz at 125 mA experienced ventricular fibrillation. In recent years, there has been a tendency in Europe to implement high voltage stunning primarily based on humanitarian grounds.…”

“…In a study conducted by Contreras and Beraquet [11], the most efficient stunning condition for blood loss was 40 V, which resulted in a 55.3 % blood loss, higher than the 35 to 50 % reported by Newell and Shaffner [13] and the 35 to 50 % blood loss obtained by Potsubay and Duduck [14]. It was also observed that only when the currents used were above 60 mA, 80 V did the birds show symptoms corresponding to the end of respiration, retention of muscular tonus and death.…”

Poultry refrigeration

“…Contreras and Beraquet (2001) found that the average shear value was significantly lower for conventionally aged and boned birds (5.2 kg/g) than for hot-boned birds (7.9 kg/g). Contreras and Beraquet (2001) found that the average shear value was significantly lower for conventionally aged and boned birds (5.2 kg/g) than for hot-boned birds (7.9 kg/g).…”