MLBA7: February / March 2009
Red discoloration of fully cooked poultry meat
Intense redness, sometimes accompanied by "bloody" liquid, has been observed in the commercial further processing industry and reported by Smith and Northcutt (2003). Intense red, bloody, localized discoloration of bone-in fully-cooked product is a severe defect. One report showed that 0.4 percent of commercial products showed this defect (Smith and Northcutt, 2003). Less research has been conducted on this type of discoloration than other meat color problems due to sporadic occurrence. Therefore, experiments were conducted to create a model system to produce red discoloration of cooked meat, then test system response by applying physical or chemical interventions (to alleviate red discoloration). A study was also conducted to attempt to identify causative agents of red discoloration.
In general, cooking to higher temperatures increased lightness and decreased redness values. Pre-freezing the marrow increased lightness and decreased redness at the lower cook temperatures of 74 and 79 degrees Celsius. Lightness values for control samples (no marrow) did not differ due to cook temperature and averaged 79.2, 79.2, and 79.4 at 74, 79, and 85 degrees Celsius, respectively. There was no difference in average redness values of control samples (0.5, 0.4 and -0.1 at 74, 79 and 85 degrees Celsius, respectively). Neither freezing nor increasing cook temperature improved either lightness or redness scores to acceptable levels.
