Effects of enhancement and nitrite-embedded packaging on dark-cutting beef color

Abstract

The objective of this study was to determine the effects of novel nitrite-embedded packaging (NEP) and enhancement on retail and cooked color and palatability of dark-cutting beef. Selection of dark-cutting beef strip loins (n = 10; pH > 6.0) and USDA Choice beef strip loins (normal-pH, n = 10) occurred at a commercial packing plant. Dark-cutting loins were divided into 2 sections and randomly selected as non-enhanced dark-cutting (DCN) and enhanced dark-cutting (DCE) treatments with 10% injection of the green weight. A final concentration of 0.5% glucono delta-lactone and 0.1% rosemary in the loin. Steaks (1.91 cm) were removed from nonenhanced normal-pH, DCN, and DCE loins. One steak from the normal-pH and DCN loins was packaged in trays overwrapped with poly-vinyl chloride, and one steak from the DCE loins was packaged in NEP. Steaks were kept in simulated retail display for 6 d with instrumental color measurements and trained color panel (n = 6) evaluation every 24 h. Remaining steaks were randomly assigned to cooked color, sensory, and Warner-Bratzler shear force. Steaks for cooked color were placed in dark storage for 72 h after packaging the DCE steak in NEP and the DCN and normal-pH steaks in vacuum packaging. A trained sensory panel (n= 6) evaluated sensory steaks for beef palatability. By d 6 of retail display, DCE steaks had greater (P < 0.05) a* values than DCN and normal-pH steaks. There was significantly more surface discoloration on normal-pH steaks than DCE and DCN steaks by d 6 of retail display. The cooked DCE steaks had similar (P > 0.05) internal a* values to cooked normal-pH steaks. A similar decrease in redness was observed by panelists evaluating the internal cooked color of DCE steaks. However, external cooked color of DCE was determined to have significantly more pink appearance than normal-pH and DCN steaks. The trained sensory panel determined there was no difference in tenderness and juiciness between the normal-pH and DCE steaks, paralleling with the Warner-Bratzler shear force results. In conclusion, NEP improved surface redness of DCE steaks during retail display, and the enhancement decreased internal redness upon cooking.