Electrical Stimulation of Intact or Split Steer or Cow Carcasses

Fifteen carcasses, 10 from steers and 5 from cows, were used for the present study. Five steer carcasses (group A) were electrically stimulated as intact, unsplit carcasses. The left sides of 5 steer carcasses (group B) and of 5 cow carcasses (group C) were electrically stimulated; the right sides of the same 5 steer carcasses (group D) and of the same 5 cow carcasses (group E) were used as controls and were not electrically stimulated. Electrically stimulated carcasses and sides (groups A and B) had brighter, more youthful colored lean, less "heat-ring" and produced more tender and more palatable rib steaks than did control sides (group D). Electrical stimulation did not (P > .05) affect ultimate pH or sarcomere length in steers or cows. Light and electron micrographs revealed increased (P < .05) structural damage (more severe contracture bands) in steer or cow muscles from electrically stimulated sides than in muscles from control sides; however, structural damage was not (P >.05) increased when intact steer carcasses were electrically stimulated and compared to unstimulated sides. Troponin-T was reduced in SDS gels of muscle from electrically stimulated, as compared to control, sides of cow carcasses (group C versus group E); no differences in percentage of protein subunits were observed between electrically stimulated and control sides of steer carcasses (group B versus group D). Electrical stimulation can be done on intact carcasses or sides of young beef to improve USDA lean maturity and lean color scores, to reduce "heat-ring" incidence and to improve tenderness.