Mechanical Tensioning of Electrically Stimulated Carcasses for Improved Tenderness

ABSTRACT

The combined effect of electrical stimulation and tensioning on tenderness was studied with cows and lambs. Each carcass was split into sides: both sides were electrically stimulated (300V.a.c., 60Hz, 120sec) within 30 min after bleeding, one side was then tensioned. At 48 hr post-stimulation, samples were taken from the semimembranosus and longissimus dorsi for shear test, sarcomere length and fiber diameter. Tensioning produced 9% and 15% decreases in shear force in the semimembranosus and longissimus dorsi respectively. Longer sarcomeres and narrower fiber diameter were also observed in tensioned muscles. All differences were significant at P < 0.05. Tensioning may be used to further improve tenderness of electrically stimulated carcasses.