The impact of slaughtering methods on physicochemical characterization of sheep myoglobin

Abstract

Recent data showed that the consumption of halal meat is increasing around the world. However, little is known about the physiochemical and digestive properties of meat prepared by this method. The aim of this study was to assess the effects of enzymatic hydrolysis with digestive enzymes on sheep meat myoglobin (Mb) prepared by two different slaughtering methods: halal slaughter (HS) and industrial slaughter (IS). The texture profile analysis (TPA) of samples and their antioxidant activity, using a Trolox equivalent antioxidant capacity scale, were determined. Mb was selected for the confirmation of digestion tests. In addition, the production of reactive oxygen species (ROS) and heme degradation of Mb samples were determined using chemiluminescence and fluorescence spectroscopy, respectively. The results showed that IS-Mb had more hydrophobicity, produced more ROS, and had a greater tendency for aggregation compared with HS-Mb. Both higher aggregation and ROS production resulted in less digestion of IS-Mb. TPA tests showed an increase in tenderness of HS samples compared with IS samples. The extent of HS samples hydrolysis was significantly greater than IS samples when treated in parallel with pancreatic enzymes. Peptides generally have significantly higher antioxidant activity than their intact parental proteins. Thus, the high antioxidant activity of HS samples is consistent with their enhanced hydrolysis. Higher aggregation and ROS production both play a crucial role in less digestion of Non-HSMb.