Two simultaneous trials were conducted to determine the effects of electrical input [electrical stunning and stimulation (ES)], wrapping, pre rigor temperature (15 °C and 38 °C) and different post rigor chilling rates on beef quality using M. longissimus lumborum (n=100). The high pre rigor temperature induced a faster pH decline than ES. The loins at 38 °C had significantly greater protein denaturation, more purge and drip loss, higher shear force values and less desmin degradation compared with the loins at 15 °C. No difference in sarcomere length was determined between the pre rigor temperatures regardless of ES and wrapping. Different post rigor chilling rates did not play a substantial role in water-holding capacity, proteolysis, or shear force values during ageing. These results suggest that high pre rigor temperature induces temperature-related toughness of muscle due to protein denaturation with subsequent limitation of proteolysis by μ-calpain, regardless of ES and wrapping treatments.
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