Effect of Carbon Dioxide Stunning and Electrical Stunning of Pigs on Postmortem Energy Metabolism and Meat Quanlity of Pork

Abstract

Stunning is a critical step to reduce the preslaughter stress and improve the meat quality. However, the differences between electrical stunning and carbon dioxide stunning are not yet clear, and the underlying mechanisms have not been elucidated. The effects of electrical stunning and carbon dioxide stunning on meat quality of Duroc× Landrace× Yorkshire (DYL) pigs were investigated. Energy metabolism, muscle fiber structure, and indicators of cell death were measured. The results showed that compared to electrical stunning, carbon dioxide stunning alleviated the depletion of glycogen and ATP, resulting in slower accumulation of lactic acid. This induced apoptosis and activated caspases and improved tenderness. ATP treatment caused the reactivation of caspases and increased meat tenderness. This study confirms the efficacy of carbon dioxide stunning in enhancing meat tenderness and provides an initial revelation of the underlying mechanisms involving energy metabolism and caspase-dependent pathways.

Keywords: Stunning, apoptosis, Tenderness, Pork