Effects of Postmortem Ph Modification and Oxygen Saturation on Lean Color Characteristics of Dark Cutting Beef

Abstract

Paired strip loins (n = 32) were obtained from four carcasses from each of the following groups: normal, 1/3, 2/3, and full dark cutting carcasses. Two pairs from each group were designated for a 7 d postmortem aging period and the other 2 pairs were aged 14 d. After each of the respective aging periods, 1 strip from each pair was randomly selected and enhanced to 110% of original weight using water, an acidic phosphate blend, NaCl and Herbalox. Upon enhancement, 2.54 cm steaks (n = 6) were fabricated from each of the enhanced and non-enhanced loins. These steaks were then subjected to a 12 hr, high-pressure (240 psi) oxygenation cycle. After the oxygenation was completed, an additional 6 steaks were cut from the enhanced and non-enhanced loins for a non-oxygenation treatment. The steaks were used for the following tests: lean color assessment, odor assessment, cooked internal lean color, thiobarbituric acid analysis (TBA), total aerobic plate counts, sensory panel, slice shear force, pH, drip loss and package headspace composition. Steaks were packaged in a modified atmosphere consisting of 80% oxygen and 20% carbon dioxide. Steaks for lean color assessment were subjected to a 14 d retail display period, whereas steaks assessed for cooked lean color, sensory panel, slice shear force and odor panel were subjected to a 7 d retail display period. High-pressure oxygenation was found to improve lean color characteristics of strip steaks derived from dark cutting carcasses while not having any detrimental effects on oxidative rancidity. Enhancement was not found to improve lean color. Enhancement did improve juiciness, tenderness and connective tissue amounts when presented before a trained sensory panel, however, uncharacteristic flavor development was a downside of the enhancement.