Fresh pork loins were cut for three replications and randomly assigned to one of seven treatments: 1) polyvinylchloride (PVC) packaged, 2) vacuum packaged (Vac-pack), 3) 0.2 mL of Tris-Buffer, 4) 0.2 mL of high leghemoglobin high pH (HLbHpH), 5) 0.2 mL of high leghemoglobin low pH (HLbLpH), 6) 0.2 mL of low leghemoglobin high pH (LLbHpH), and 7) 0.2 mL of low leghemoglobin low pH (LLbLpH). Treatments 3 through 7 also were vacuum packaged. Leghemoglobin (Lb) protein treatments improved (P<0.05) the visual color of vacuum packaged pork at the point of purchase. CIE L* values were not affected by HLbHpH, LLbHpH or LLbLpH treatments. However, the HLbLpH treatment was lighter (P<0.05) than the vacuum packaged control treatments on days 3, 4, and 5. High Lb (HLb) treatments had a positive effect (P=0.0116) on the CIE a* values on the day of manufacture. HLbLpH treatment eIE b* values were higher (P<0.05) than Vac-pack and buffer controls from day 0 to day 5. On the day of processing, HLb treatments were higher (P=0.0637) in oxymyoglobin than low Lb treatments. Metmyoglobin of HLb treatments was higher (P<0.05) than the Vac-pack and the buffer treatments on the day of manufacture. pH did not affect (P>0.05) sensory or objective color, pigment state, purge or total psychrotrophic aerobic bacterial counts (TPC) throughout the study. Lb treatments TPC were lower (P<0.0l) than nontreated samples at all assessment times. / Master of Science