Effects of electrical stunning frequency and voltage combinations on the presence of engorged blood vessels in goose liver.

The purpose of this study was to investigate the influence of nine electrical stunning methods using various frequency and voltage combinations on the occurrence of engorged blood vessels in goose liver. Two hundred seventy Gourmaud geese (liver-type line SI 14) were slaughtered at 12 wk of age, in groups of 90 at three different times. Thirty birds each were subjected to one of the nine stunning methods. Neck cutting was performed immediately after stunning. The duration of exsanguination was 11 min. After completion of bleeding, the birds were scalded, defeathered manually, and kept refrigerated. At 1 d postmortem, the carcasses were eviscerated and cut up. From the slaughterhouse, the livers chilled in ice were transported to the cannery where they were weighed and graded at 2 d postmortem and were further processed. All of the veins and capillaries full of blood were removed from livers, because their presence was a hazard to product quality by causing discoloration of the canned liver, and the percentage of liver weight loss was then determined. The loss in liver weight due to removal of engorged blood vessels was reduced (P < 0.05) at 350 Hz, 70 to 90 V, and 80 to 85 mA when compared to the results obtained with any other stunning method tested. It was concluded that the use of high-frequency currents for electrical stunning of liver geese might have considerable commercial advantages.

The effects of electrical and controlled atmosphere stunning methods on meat and liver quality of geese.

The objective of this research was to investigate the effects of electrical and gas stunning on the meat and liver quality characteristics of liver geese. Sixty birds were slaughtered at 12 wk of age, in groups of 20 at three different times. Thirty birds each were subjected to one of the two stunning methods. Deboned breast fillets and thigh muscles were evaluated for hemorrhaging, amount of blood in the veins, and color by using a visual grading system. Livers were removed from carcasses during evisceration and were subsequently graded. Besides external color and hemorrhaging, the degree of liver weight loss due to removal of blood vessels was also determined. The use of controlled atmosphere stunning significantly reduced the incidence of muscle hemorrhages when compared to electrical stunning. However, no significant difference was found for color or amount of blood remaining in the veins of muscles between geese receiving electrical or controlled atmosphere stunning. The hemorrhaging and color scores of livers from gas-stunned birds did not differ from those of electrically stunned birds. As for the liver weight loss caused by removal of veins and capillaries, stunning treatment had no significant effect on this parameter. These results suggest that controlled atmosphere stunning produced slightly better quality goose meat but did not improve liver quality when compared to the electrical stunning method used.

Occurrence of anaerobic bacterial, clostridial, and Clostridium perfringens spores in raw goose livers from a poultry processing plant in Hungary.

Anaerobic bacterial, clostridial, and Clostridium perfringens spores were enumerated in raw goose liver samples taken after evisceration of the birds (EB) in the slaughterhouse and after removal of blood vessels from the liver (RBVL) in the cannery. The samples taken after RBVL had significantly higher (P < 0.05) spore counts than did those taken after EB, indicating contamination of livers during processing. The number of C. perfringens spores was one log cycle higher in the samples taken after RBVL than in those taken after EB (P < 0.05). The confirmation of C. perfringens according to the profiles of Rapid ID 32 A tests was carried out by means of the ATB Plus computer program. With an identification percentage of 99.9 and a T-value of 0.65, the suspect colonies proved to be C. perfringens. Therefore, the importance of an appropriate cleaning and sanitation program and of personnel hygiene should be emphasized in the industry.