Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: March 18, 1996
Publication Date: N/A
Technical Abstract: The objectives were 1) to determine the effectiveness of calcium chloride when injected later than 2 d postmortem, and 2) to determine the effect of extended post-injection aging time. The longissimus thoracis et lumborum was obtained at 2 d postmortem from the carcasses of ten 19-mo-old crossbred cull heifers. The longissimus from alternating sides was divided into halves and each half was injected on either d 2 or d 14 postmortem with 5% by weight of a 200 mM calcium chloride solution. Each half was then divided into quarters and each quarter aged (1 deg C) either 7 or 35 days post-injection. The non- injected control longissimus from the other side was divided into quarters and each quarter aged 9, 21, 37, or 49 d. Color steaks were overwrapped with PVC film and displayed at 1 deg C for 7 d under 2152 lx of ultralume fluorescent light. Calcium chloride injection regardless of inject time or post-injection aging time had higher (P < .05) tenderness rating than control with the same total aging time (5.2, 5.5, 5.8, and 6.1 vs 4.3, 4.8, 5.1, and 5.3, respectively). Calcium chloride injection at d 14 reduced shear force (.7 kg) and increased tenderness rating (.7 units) as effectively (P < .05) as injection at d 2 (1.1 kg and .7 units, respectively). Lean color and surface discoloration scores were not affected by calcium chloride injection or post-injection aging time through 7 d display time. Calcium chloride injection can be effectively applied as late as 14 d postmortem. Extended aging after injection (35 d) does not affect subsequent lean color during retail display.