This study examined the relationship between meat color and myoglobin content, and evaluated their influence on muscle fiber characteristics and overall pork quality. Four groups of pigs were classified by lightness (CIE L * ) and redness (CIE a * ): HH, high lightness and high redness; HL, high lightness and low redness; LH, low lightness and high redness; LL, low lightness and low redness. Myoglobin content ranged from 1.2 mg/g to 2.1 mg/g, and was highest in the LH group and lowest in the LL group (p<0.05). Myoglobin content correlated significantly with redness (CIE a * ) (r = 0.45, p<0.01). Fiber compositions of type I and IIA were closely related to lightness and redness. Pork with higher sizes of type IIA and IIB fibers had lower lightness and redness, respectively, which was tougher than the other pork. Pork having the highest lightness and lowest redness, often considered "pale", has higher values in drip loss than the other classes of pork tested.

These results indicate that active packaging using self-CO -generation materials can extend the shelf life similarly to that observed with vacuum packaging, and that the active packaging method can improve the quality characteristics of beef during cold storage. © 2017 Society of Chemical Industry.

The objective of this study was to evaluate the effect of feeding soybean oil (SO) with varying levels of peroxidation on carcass traits and shelf life of loins. Fifty-six barrows were randomly assigned to 1 of 4 diets containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each infused with air at a rate of 15 liter/min. Individually housed pigs were provided ad libitum access to feed for 81 d. At 82 d, pigs were slaughtered and hot carcass weight and liver weights were recorded. Carcass characteristics and fresh loin quality were evaluated 1 d postmortem. Loin chops from each carcass were overwrap-packaged and subjected to a 10-d simulated retail display. Daily measurements of L*, a*, b*, reflectance, and visual discoloration were conducted, evaluation of cooking loss and Warner-Bratzler shear force (WBSF) was conducted on chops stored 0, 5, and 10 d, and thiobarbituric acid reactive substances (TBARS) were evaluated on chops stored 0 and 10 d. Shelf life-related data were analyzed as a completely randomized design with repeated measures in time, with storage location (shelf) as a random effect. Carcasses of 90 °C pigs weighed 6.0, 8.6, and 6.9 kg less (P < 0.03) than 22.5 °C, 45 °C, and 180 °C carcasses, respectively. Livers of 90 °C and 180 °C pigs were 14.3% and 11.7%, respectively, heavier (P ≤ 0.02) than those from pigs fed 22.5 °C SO, with livers of 45 °C being intermediate. Livers of 90 °C pigs represented 0.12 percentage units less (P = 0.02) of ending live weight than livers of 180 °C pigs, and 180 °C livers were 0.12 percentage units less (P < 0.01) of ending live weight than those from pigs fed 22.5 °C SO, with 45 °C being intermediate. There was no difference (P ≥ 0.19) in back fat depth, loin muscle area, or estimated carcass lean percentage among SO treatments, nor was there an effect (P ≥ 0.13) of SO on any early post-mortem loin quality traits or loin composition. There was no effect (P > 0.14) of SO on cooking loss, WBSF, L*, a*, b*, hue angle, reflectance, discoloration, or TBARS; however, there was a tendency (P = 0.09) for chops of 45 °C pigs to have greater (P < 0.04) chroma than either 22.5 °C or 180 °C, with 90 °C being intermediate. Overall, feeding SO cooked at 90 °C for 72 h resulted in reduced carcass weight and dressing percentage; however, there was no evidence that feeding peroxidized SO was detrimental to shelf life of loin chops.

The objective of this study was to investigate the relationship between measurements of color and water-holding capacity (WHC) in pork loin. A total of 419 pork loins were sampled from crossbred (Landrace×Jeju native black pig) F2 pigs at a commercial slaughter house. Meat color measurements (CIE L*, a*, b*), chroma (C*) and hue angle (h) were measured with the Minolta Chromameter and WHC was measured by filter paper fluid, drip loss and cooking loss. Also pH, moisture content and crude fat content were measured at 24 hr postmortem. CIE L*, b* and h values had positive correlation with drip loss (r=0.52, 0.42), but CIE a* and C* values were not related to drip loss. Results showed that CIE L*, b*, and h color system was better than CIE L*, a*, b* color system to predict WHC, especially drip loss. pH was negatively correlated to drip loss (-0.42) and CIE L* (-0.67). Although CIE L* and pH were correlated to drip loss, the accuracy of their estimates for drip loss was 27% and 17%, respectively. Consequently, it was confirmed that meat color and WHC were not perfectly related and suggested that CIE L*, b*, and h color space should not be used independently to predict WHC of pork loin.