Location: Agroecosystems Management ResearchTitle: Influence of feeding thermally peroxidized soybean oil to finishing pigs on carcass characteristics, loin quality, and shelf-life of loin chops
|OVERHOLT, MARTIN - University Of Illinois|
|KIM, GAP-DON - University Of Illinois|
|BOLER, DUSTIN - University Of Illinois|
|DILGER, ANNA - University Of Illinois|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2018
Publication Date: 7/10/2018
Citation: Overholt, M.F., Kim, G., Boler, D., Kerr, B.J., Dilger, A. 2018. Influence of feeding thermally peroxidized soybean oil to finishing pigs on carcass characteristics, loin quality, and shelf-life of loin chops. Journal of Animal Science. 96:2710-2722.
Interpretive Summary: In animal production, interest in dietary lipid quality has focused on the influence of fatty acid profile on subsequent carcass and pork product quality. Recently however, it has been recognized that the oxidative status of the oil fed to finishing pigs is also important. The current study was conducted to determine the effect of feeding divergently thermally processed soybean oil on carcass characteristics, early post-mortem loin quality, and shelf-life of loin chops. Data from this experiment indicated that feeding highly peroxidized soybean oil resulted in reduced carcass weight and dressing percentage; however, there was no evidence that feeding peroxidized soybean oil was detrimental to shelf-life of loin chops. This information is important for nutritionists at universities, feed companies, and pig production facilities showing that finishing pigs fed highly peroxided soybean oil has minor effects on carcass weight, and no effect on pork loin quality or shelf life.
Technical Abstract: 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 15L/min. Individually housed pigs were provided ad libitum access to feed for 81 d. At 82 d pigs were slaughtered and hot carcass weight (HCW) and liver weights were recorded. Carcass characteristics and fresh loin quality were evaluated 1 d post-mortem. 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 were conducted on chops stored 0, 5, and 10 d, and thiobarbituric acid reactive substances (TBARS) were evaluated on chops stored 0 and 10. Shelf-life related data were analyzed as a completely randomized design repeated 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 than (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 180°C, and 180°C liver 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) BF depth, LMA, 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.