The Effect of Dietary Selenium on Pork Carcass Quality and Longissimus Color Stability

University of Nebraska 2007 Swine Report. Selenium (Se) -supplemented diets during the growing-finishing period alter pork quality, thereby affecting pork value. The objective of this study was to evaluate the effects of dietary Se on carcass quality and color stability in the pork longissimus dorsi (LD) muscle when added to growing-finishing diets. Thirty pigs weighing ?50 lb were selected for the study. Three pigs were assigned to each of 10 pens and fed one of five treatment diets: Basal/Control (1), Basal + 0.15 ppm (2) or 0.30 ppm (3) Se from inorganic (selenite) Se, Basal + 0.15 ppm (4) or 0.30 ppm (5) Se from organic (selenized yeast) Se. The feeding period continued for 80 days, at which time the final market weight (?250 lb) was achieved. One boneless chop from the 10th to 13th thoracic portion of the LD was assigned to 48-hour drip loss and two remaining chops were aged for 7 days and then used for retail color stability measurements (?Ecmc, L*, a* and b*); evaluation of color continued through day 12. The organic 0.30 ppm Se treatment resulted in the highest ?Ecmc values, while the organic 0.15 ppm Se treatment and the control had the lowest ?Ecmc. As time progressed, L* values increased for all treatments, except those supplemented with 0.15 ppm organic Se (P < 0.05). As time progressed, regardless of treatment, a* values decreased (P < 0.0001). Diets containing 0.30 ppm Se had lower b* values when compared to the control (P < 0.05). During the 12-day period shelf life study period, there was a significant decrease in b* value from day 3 to 12 (P < 0.0001). Pigs fed diets supplemented with Se have a different LD color during storage that is lighter, less red, and less yellow. In addition, the use of organic Se results in the greatest overall color differences over time. Therefore, producers desiring to raise pork with a darker lean color should carefully evaluate the impactof dietary Se supplementation.