Effects of Electrical Stimulation on Quality and Microstructure of Rapid Chilled Beef Carcasses

Abstract

A total of 15 beef were used to examine the effects of rapid chilling (RC) and electrical stimulation (ES) on meat quality and microstructure of longissimus dorsi thoracis (LDT). After slaughter, the right sides of carcasses were randomly assigned ES (500 V, 50 Hz, and 120 s), while the left sides remained as control (NES). Then, carcasses were rapidly chilled (-20+/-1 degrees C) for 6 h and placed in a conventional chiller (2+/-1 degrees C). Meat quality was evaluated by water holding capacity (WHC), cooking loss (CL), color (L*, a*, b*), shear force (SF) and sarcomere length (SL). As a result, ES had no impact on WHC, CL and color of LDT from rapid chilled carcasses (P < 0.05). Tenderness and SL values were significantly increased in stimulated carcasses at 2, 7 and 10 d postmortem (P < 0.001). Also, microstructure examination of LDT demonstrated that amorphous appearance of the myofibres was found in ES due to the rupture of M-lines and I-bands. The results showed that ES is a useful method for improving tenderness of LDT during storage time and the disadvantageous effect of RC on WHC, CL, and color was equalized.