Electrical stunning in pig slaughtering in Vietnam: meat processors’ perceptions and the effects on pork quality

Pre-slaughter stunning is essential to ensure that animals are rendered unconscious and insensible to fear, pain, and distress. However, this practice is uncommon in the predominant small-medium scale slaughterhouses in Vietnam due to traditional slaughter practices and beliefs that electrical stunning may affect meat quality. This study aimed to (i) understand the perceptions and practices of meat processors regarding pre-slaughter stunning, and (ii) evaluate the effects of electrical stunning on pork quality. In December 2024, face-to-face interviews were conducted with 27 small- and medium-scale pig slaughterhouse owners and meat processors across three districts in Hanoi, using a structured questionnaire. In parallel, an experimental trial was conducted with 30 healthy Duroc (Landrace×Yorkshire) pigs, randomly assigned to two groups. One group underwent electrical stunning before slaughter, while the other was slaughtered without stunning (direct bleeding). pH, meat color, 24-hour post-mortem drip loss, cooking loss ratio, and tenderness of the longissimus dorsi muscle were measured for pork samples. Meat from both groups was also processed into ‘giò’, a traditional Vietnamese pork sausage, and evaluated through sensory analysis. The results showed that most respondents lacked adequate knowledge of stunning prior to slaughter. Furthermore, 59.3% expressed concern that stunning could negatively impact the quality of pork and pork sausage. No significant differences were observed between the two groups in pH, meat color, drip loss, cooking loss, or tenderness. Sensory evaluation of the pork (sausage) revealed no significant differences in most attributes. Pork from electrically stunned pigs, characterized by flat, smooth slices, non-sticky texture, and distinctive light pink color, was rated higher than that from non-stunned pigs. These findings highlight the need for improved awareness and understanding of stunning practices among stakeholders. Ongoing research, policy development, and stakeholder outreach are essential to enhance awareness and adoption of humane stunning practices, thereby improving animal welfare standards in Vietnam.