Effect of Vitamin E, Irradiation, and Display Time on the Quality and Sensory Characteristics of Pork

90 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2002.Irradiation has been approved for use in meat products because of the high risk of microbial contamination. However, irradiation has been associated with the generation of off odors and color changes in meat products. The objective of this study was to evaluate the effect of dietary vitamin E on the incidence of off odors and color changes in pork exposed to low dose irradiation. Pigs (n = 4/dietary treatment, 3 replications) were fed supplementary dietary vitamin E (0, 100, 200, and 300 mg/kg of feed) treatments (above basal vitamin E-26 mg/kg feed) for 6 wks. After slaughter and fabrication (24 h postmortem), the Boston butts and the Longissimus were obtained. Chops (2.5 cm thick) from the Longissimus were randomly placed into 2 bags (5 loins/bag) and vacuum packaged and each bag randomly served as control or was irradiated (1.5 kGy). The loin chops were transferred into Styrofoam trays, PVC overwrapped, and held in a display case to evaluate changes in color and lipid oxidation, after 0, 3, and 9 d of display. Also, the Boston butts were ground and packaged in duplicate. Each package randomly served as a control or was irradiated. Patties were fashioned, packaged in overwrapped Styrofoam trays, and set in a display case. Samples were evaluated for color, odor, and lipid oxidation at 0, 4, and 8 days. All samples for sensory evaluation were held in display for 3 d and cooked to 70°C internal temperature. Lipid oxidation increased with storage time. Vitamin E had no effect on color, odor, and lipid oxidation; however, it increased the juiciness of ground pork. Irradiation increased a* value, brown and gray colors, and increased "wetdog" flavor regardless of vitamin E supplementation. Irradiation consistently decreased rancid, putrefying, and fishy odors with longer display time. These results indicate that vitamin E cannot be used in minimizing off flavors/odors and color changes in ground pork.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD