title: The impact of postharvest interventions on the color stability and, subsequently, the palatability of beef from cattle fed wet distillers grain.
abstract: Two hundred forty heifers were fed at Oklahoma State University in Stillwater, OK, in 1 of 2 treatment groups: a dry rolled corn (CON) diet or a diet including 30% wet distillers grains plus solubles (WDGS). Chuck rolls (n = 60) and paired strip loins (n = 75 pairs; 38 CON and 37 WDGS) were collected from each treatment group and processed at 3 d and 14 d, respectively. After grinding, each chuck was separated into 8 polyvinyl chloride (PVC) film overwrapped packages and 8 high oxygen modified atmosphere packaging (MAP), each containing approximately 0.23 kg of ground beef, for evaluation by a trained color panel, a trained color panel and a trained sensory panel and for thiobarbituric acid reactive substance (TBARS) analysis. After 14 d, 1 strip loin from each pair was injected with an enhancement solution. Steaks from each strip loin were fabricated and packaged, one-half in PVC and one-half in MAP. In addition to the evaluation by trained color and sensory panels and TBARS analysis, steaks were subjected to instrumental color evaluation using a HunterLab Miniscan XE and Warner-Bratzler Shear Force analysis using an Instron Universal Testing Machine. Ground beef exhibited no significant differences in color between dietary treatments; however, sensory panelists did find MAP WDGS had less beefy flavor (P = 0.05) and more painty flavor (P = 0.01) intensities than the MAP CON ground beef. Cattle fed WDGS discolored more (P = 0.01) and had less bright steaks than cattle fed the CON when MAP and enhanced. Distillers fed, nonenhanced (nonE) MAP steaks were redder and yellower than control steaks (P < 0.05) on removal from simulated retail display. There were no other significant (P > 0.05) color differences between dietary treatments using any other combination of postharvest interventions. Sensory panel results indicated WDGS NE PVC products were juicier and more tender (P < 0.05), initially, and contained less connective tissue (5.3 ± 0.1, 5.5 ± 0.1, and 5.9 ± 0.4, respectively) than the steaks from CON carcasses (5.1 ± 0.1, 5.4 ± 0.1, and 5.8 ± 0.4, respectively). Although WDGS NE MAP steaks showed more oxidation than CON NE MAP steaks on removal from retail case, all TBAR values were well below a threshold of 1 mg malonaldehyde/kg. Essentially, MAP but not enhancing products from cattle fed WDGS may be the best way to maintain a visually appealing appearance in the retail case but at possible risk to product juiciness.
authors.affiliation: Animal Science Department, Oklahoma State University, Stillwater 74078, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Knobel
authors.forename: G G
authors.initials: GG
authors.lastname: Mafi
authors.forename: C Mireles
authors.initials: CM
authors.lastname: De Witt
authors.forename: J B
authors.initials: JB
authors.lastname: Morgan
authors.forename: C J
authors.initials: CJ
authors.lastname: Richards
authors.forename: D L
authors.initials: DL
authors.lastname: VanOverbeke
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000502:physiology*; D004032:Diet / Q000662:veterinary*; D002523:Edible Grain / Q000737:chemistry*; D005260:Female; D008460:Meat / Q000592:standards*; D011897:Random Allocation; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D017392:Thiobarbituric Acid Reactive Substances