Oxidation Products in Chicken Meat After Frozen Storage, Microwave and Convection Oven Cooking, Refrigerated Storage, and Reheating

Abstract

Oxidation products were measured in chicken breast and leg meat during a series of common household processing steps (frozen storage, microwave and convection cooking, refrigerated storage after cooking, and reheating). Malondialdehyde (MDA) in fat from meat was measured by an improved thiobarbituric acid (TBA) assay with antioxidant protection; and fluorescent products (FP) were measured in organic and aqueous layers from Folch-extracted meat samples by fluorescence spectrophotometry. Fat from breast meat contained almost twice as much MDA and FP than fat from leg meat due to a greater content of phospholipids, which had a large amount of polyunsaturated fatty acids. Leg meat had higher TBA numbers, however, because it contained twice as much fat as breast meat. Fresh, 3-month, and 6-month frozen storaged meats cooked by convention oven and then further processed had higher MDA and TBA values compared with microwave cooked and processed meats, but a significant difference (P<.05) was observed only in meat stored for 6 months. The relative levels of FP in the organic layers from meats cooked by convection oven were not significantly higher than meats cooked by microwave. However, the relative levels of FP in aqueous layers were significantly higher after convection compared to microwave cooking, and these differences persisted throughout further processing steps. Frozen and refrigerated storage of meat produced more substantial oxidative decomposition of fats than did cooking, but cooking produced substantial increases in aqueous-soluble FP. Generally, it is concluded that the absolute level of oxidation products in chicken meat after a particular food processing step depends primarily on the level of oxidation products present before that step.