Effect of low voltage electrical stimulation and temperature conditioning on postmortem changes in glycolysis and calpains activities of Korean native cattle (Hanwoo)

The combined effects of low voltage electrical stimulation (LVES) and temperature conditioning during early postmortem (PM) ageing on glycolytic rates and calpains activities of Korean native cattle (Hanwoo) were determined. M. longissimus was taken after splitting course, divided into three pieces and temperature conditioned at 2, 16, and 30°C for 3 h PM. The PM glycolytic rates, calpains and calpastatin activities were measured at 1, 3, 9, and 24 h PM. Although both LVES and the 30°C treatment accelerated glycolytic rates and resulted in improved enzyme activities, LVES was more effective for the improvement of enzyme activities than the 30°C treatment. Among tested Rigor-values (R-value; R248, R250, and R258), R258 showed the highest correlation with pH (r=0.814, P<0.01), glycogen content (r=0.784, P<0.01) and μ-calpain (r=0.838, P<0.01) and selected as a suitable parameter to predict glycolytic rate. The high correlation coefficients between μ-calpain activity and metabolic rate parameters suggest that the change in the enzyme activity is closely related to glycolytic rates. The LVES in combination with the 30°C treatment until 3 h PM was the best treatment to accelerate the glycolytic rate and to improve the calpains activities in Hanwoo tissue.