50 Implications of a Thermoforming Vacuum Packaging or Overwrap Packaging Method on a Simulated Retail Display of Longissimus Lumborum Steaks

Abstract

Abstract Fresh surface color of beef remains a focus for consumers at the time of purchasing in the retail sector. The objective of this study was to evaluate instrumental surface color, expert color evaluation, and lipid oxidation (TBARS) on beef longissimus lumborum steaks packaged using recycle-ready film (RRF) or polyvinyl chloride overwrap (PVC). Paired strip loins (IMPS # 180), fabricated from beef carcasses (n = 7) 10 d postmortem, cut into 2.54 cm-thick steaks, and assigned to one of two packaging treatments RRF (OTR = 0.8 cc/m2/24 h) or PVC (OTR = 14,000 cc/m2/24 h). Steaks were stored under simulated retail conditions (3 °C ± 1.5 °C) in a LED (2297 lux) lighted, three-tiered retail cabinet, rotated daily among shelves for 35 days. From d 0 to 35 objective surface color was captured every 5 days to record changes in lightness (L*), redness (a*), yellowness (b*), Chroma, Hue Angle, and calculated values of spectral wavelengths (Red to Brown, Oxymyoglobin, Deoxymyoglobin, & Metmyoglobin) using a HunterLab colorimeter. Steaks packaged in RRF became lighter (L*) as display period increased (P < 0.05), whereas steaks packaged in PVC became darker (P < 0.05). Redness (a*) values were greatest (P < 0.05) for PVC steaks until day 5, whereas RRF steaks had greater (P < 0.05) surface redness from day 10 to 35 of the display period. Calculated spectral values red to brown were greater (P < 0.05) for steaks in RRF than PVC. Expert color evaluators rated RRF steaks having less browning and less discoloration (P < 0.05) from day 5 to 35 of display. Lipid oxidation was greater (P < 0.05) for PVC steaks from day 10 through day 35 of the display. These results suggest that the use of RRF vacuum packaging for beef steaks is plausible and can maintain surface color characteristics during extended display periods.