Effect of NaCl, myoglobin, Fe(II), and Fe(III) on lipid oxidation of raw and cooked chicken breast and beef loin.

Chicken breast and beef loin were ground, and no, NaCl, NaCl+myoglobin, NaCl+Fe(II), or NaCl+Fe(III) additions were made; patties were then prepared. Half of the patties were packaged in oxygen-permeable bags and stored at 4 degrees C for 10 days, and the other half were cooked in a 95 degrees C water bath to an internal temperature of 75 degrees C, packaged in oxygen-permeable zipper bags, and stored at 4 degrees C for 7 days. The oxidative stability of raw and cooked chicken breast and beef loin were determined during storage. Chicken breast was more resistant to various exogenous oxidative factors than beef loin: addition of NaCl did not increase TBARS values and nonheme content of raw chicken breast, but significantly increased those of raw beef loin patties during storage. Addition of NaCl+Mb did not affect lipid oxidation in raw chicken breast patties, but decreased the TBARS of beef loin during storage. Addition of NaCl+Fe(III) or NaCl+Fe(II) increased the TBARS values of both raw chicken breast and beef loin during storage, but the increase was greater in beef loin than in chicken breast. The TBARS values of all cooked chicken breast and beef loin increased during 7 days of storage, but the increases in cooked chicken patties were significantly smaller than those of cooked beef loin patties with the same treatments. Addition of NaCl and cooking caused severe degradation of myoglobin, leading to a significant increase in free ionic iron content in beef loin. It is suggested that free ionic iron is the major catalyst for lipid oxidation, and the low "storage-stable and heat-stable" ferric ion reducing capacity in chicken breast were responsible for the high oxidative stability for raw and cooked chicken breast compared with beef loin under prooxidants, cooking, and storage conditions.