Effects of Various Fresh Meat Storage Methods on the Color of Cooked Ground Pork
Journal of Muscle Foods
The effects of microbial growth in raw materials on cooked pork color were investigated. In two trials with sow meat held aerobically at 2C for 3 weeks, microbial load reached spoilage levels (107 cfu/g), pH increased to 6.46, and samples cooked to 71C had red exudate, shown by absorption spectroscopy to contain myoglobin and cytochrome c. Samples cooked to 82C also received high panel ratings for red color, due to red, flocculent precipitate in the exudate, but undenatured myoglobin levels were low. In sow meat held frozen or vacuum-packaged at 2C, pH after 3 weeks was 6.03 and 6.18, and plate counts were 104 and 107, respectively, but exudates after cooking were much less red. In five trials with fresh pork legs, total plate counts also reached 107 cfu/g by 3 weeks storage, and pH increased to 6.37, but cooked samples were not red. Higher myoglobin levels in sow meat probably accounted for the red color and level of undenatured myoglobin remaining after cooking of high pH, spoiled samples.
Cornforth, D.P., Ghorpade, V.M. and Kim Y. 1993. Effects of various fresh meat storage methods on color of cooked ground pork. J. Muscle Foods 4:57.