EVALUATION OF MALONALDEHYDE AS A MARKER OF OXIDATIVE RANCIDITY IN MEAT PRODUCTS

Quantification of malonaldehyde as a marker of lipid oxidation in comminuted meat systems, with or without additives, by a distillation and an extraction procedure was investigated. Each method had its own benefits and drawbacks. The extraction procedure generally afforded more realistic results. However, presence of colored additives such as the cooked cured-meat pigment, as well as dispersed lipids in the extracts, interfered with accurate determination of the colored chromogen between malonaldehyde and the 2-thiobarbituric acid (TBA) reagent. On the other hand, the distillation procedure afforded higher TBA values as compared to the extraction method since decomposition of labile hydroperoxides occurred. Addition of antioxidants to the mixtures prior to distillation proved beneficial in some cases. In the presence of residual nitrite, addition of sulfanilamide to the mixture prior to distillation prevented underestimation of malonaldehyde presumably by inhibiting its nitrosation.