High Oxygen Modified Atmosphere Packaging Negatively Influences Consumer Acceptability Traits of Pork

Abstract

Current trends in meat packaging have seen a shift from conventional overwrap to vacuum packing (VAC) and modified atmosphere packaging (MAP). The aim of this experiment was to investigate the effects of high oxygen MAP (HiOxMAP) of pork loins compared with vacuum packed (VAC) on eating quality and colour, after storage in simulated illuminated retail display conditions. Pork loins (n = 40) were cut and stored under two packaging methods (HiOxMAP, 80% O2, 20% CO2; VAC) for up to 14 days, with samples taken at various times for measurements. After 7 days of storage, HiOxMAP samples exhibited inferior consumer acceptability for tenderness, flavor, overall liking, quality and re-purchase intention as well as higher shear force and hardness, relative to VAC samples (p < 0.05 for all). Loins stored in HiOxMAP had higher lightness (L*), redness (a*) and yellowness (b*) values at 3 and 7 days, but lower ratio of oxymoglobin to metmyoglobin (oxy/met) values in the meat surface at 14 days of display, relative to VAC samples (p < 0.05 for all). The oxy/met ratio declined from 2.3 to 1.7 between days 3 and 14 of display in HiOxMAP samples (p < 0.05), whereas the ratio was similar and stayed relatively high for VAC samples. VAC samples produced consistently higher colour values (a*, b*, oxy/met) when left to bloom 30 min after removal from packaging (p < 0.05). Lipid oxidation values, measured using thiobarbituric acid reactive substances, in HiOxMAP pork loins, were higher at all time points compared to VAC during the 14 day storage period (p < 0.05). The use of vacuum packing for retail shelves, should be considered as the preferred option, over HiOxMAP.

Effectiveness of Sprayed Bioactive Fruit Extracts in Counteracting Protein Oxidation in Lamb Cutlets Subjected to a High-Oxygen MAP

“…The effect of the packaging strategy on lipid oxidation was remarkable and, in this case, both TBARS and hexanal measurements agreed in showing significantly higher oxidation levels in refrigerated and cooked meats packed in MAP-C than in those packed in Vacuum-C. The high concentration of molecular oxygen in MAP is known to facilitate the onset of a pro-oxidative environment that leads to increased lipid oxidation rates [ 11 , 12 ]. The pro-oxidant effect of High-Ox-MAP on lipid oxidation has been reported for pork steaks [ 12 ], chicken drumsticks [ 40 ], beef muscles [ 41 ] and lamb cutlets [ 17 ], among others.…”

“…This effect is particularly remarkable in red meat subjected to a high-oxygen modified atmosphere packaging (High-Ox-MAP) [ 10 ]. The necessity of guaranteeing the formation of oxymyoglobin and the display of a desirable bright red color gets into conflict with the onset of oxidative reactions, with the latter being significantly stimulated in meat stored in High-Ox-MAP [ 11 , 12 ]. Increasing oxygen concentration in MAP leads to increased lipid and protein oxidation rates and that is reflected in altered texture traits and low consumer acceptability [ 11 , 13 ].…”

Consumer Preferences and Acceptance of Meat Products

“…The final two research articles focusing on postmortem factors that influence consumer eating quality dealt with extended postmortem aging of beef [5] and modified atmosphere packaging of pork [6]. Garmyn et al [5] investigated the effect of extending the postmortem aging of beef strip loins from 21 to 84 days.…”

“…Based on their results, samples should not be wet-aged longer than 63 days to prevent negative eating experiences for consumers; however, storage conditions (i.e., temperature) could potentially be adjusted to accommodate longer chilled storage without compromising flavor and overall palatability to the same extent [5]. Peng et al [6] investigated the effects of high oxygen modified atmosphere packaging (MAP) of pork loins compared to vacuum packaging on eating quality and color following presentation in simulated retail display conditions. Ultimately, retailers should consider vacuum packing the preferred option over high-oxygen MAP, given the inferior consumer acceptability for palatability traits and greater lipid oxidation of MAP samples.…”

“…Five of the original research articles focused on the influence of postmortem factors, such an enhancement [ 2 , 3 ] or incorporation of non-meat ingredients [ 4 ], postmortem aging [ 5 ], and packaging [ 6 ] on consumer eating quality. Lees et al [ 2 ] assessed the impact of kiwifruit extract (actinidin) on consumer sensory outcomes for beef strip loin and outside flat.…”