| This study investigated the effects of adverse environmental conditions on the muscle properties of poultry meat. Analyses of water-holding properties of chicken meat showed that breast meat was more sensitive to antemortem temperature than leg meat. Meat from chickens exposed to preslaughter heat (40{dollar}spcirc{dollar}C for 1 h) lost significant amounts of drip during the crucial processing period--the first 6 h post-mortem. Preslaughter thermal preconditioning (physiological acclimatization) did not prevent the loss in water-holding properties associated with heat. Breast meat from thermally preconditioned and heat shocked chickens appeared pale, soft, and exudative, similar to the PSE condition found in pork.; The "PSE-like" condition was further evaluated by analyzing color, water-holding and gelation properties of turkey breast meat which was visually selected during processing. Pale or "PSE-like" breast meat was significantly (p {dollar}<{dollar} 0.05) lighter (lower L value) in color than control; however, there was no difference in reddness (+a) or yellowness (+b). Water-holding and gelation properties were similar for pale and control meat. When adjusted to pH 6.4, the functional properties of pale and control meat gels increased, thus indicating that pale myofibrillar proteins were not irreversibly denatured as they are with PSE pork meat.; In the final study, functional properties of raw breast meat from turkeys given antemortem heat and physical (exercise) stress were compared. Meat from all treatments reached the same ultimate pH, but the pH of meat from heat stressed turkeys declined more rapidly during the first 15 min post-mortem. In general, birds in control and physical stress treatments had similar breast meat pH, water-holding properties, color, and stress relaxation parameters. Stress relaxation data showed more variation with treatment when deformation was applied parallel to muscle fiber orientation, instead of perpendicular, which suggested that antemortem stress had a greater effect on myofibrillar structure than connective tissue.; The results of this study showed that antemortem treatment affected post-mortem muscle characteristics of poultry. However, "PSE-like" poultry meat does not have the physical properties normally associated with PSE pork. Additional knowledge in this area would provide opportunities to further improve poultry meat quality. |
