Use of Soy Lecithin to Improve Nutritional Quality of Poultry Meats and its Effect on Stability and Sensory Attributes

摘要

Enhancing polyunsaturated fatty acid content of poultry meats can be associated with chemical oxidative stability and loss of sensory quality. In this study, broiler breast and leg muscle meats were examined from birds fed graded levels of soy lecithin {e.g. 0% (OL); 25% (25L); 50% (50L); 100% (100L)}, as a replacement for tallow in a standard poultry diet. Poultry breast and leg meats were analyzed for fatty acid content and oxidation products (TBARS), in freshly cooked and also on 5-day cold storage products, respectively. Cook-loss of meats were significantly (P<0.05) higher in birds fed the lecithin diets; this corresponded to relatively lower (P<0.05) phospholipids content remaining in cooked meats, compared to tallow fed controls. PUFAs consisting of linoleic and a-linolenic (a-LA) specifically, were both significantly (P<0.05) higher in breast and leg muscle meats, respectively, when derived from birds fed 50-100% soy lecithin replacement diets. Presence of highly unsaturated omega-3 was negligible and no change occurred with feeding diets. Increases in total PUFA content corresponded to reductions in MUFA with no changes in SFAs in lecithin fed birds. Changes in P/S ratios in 5-day refrigerated stored, cooked breast and leg products derived from birds fed lecithin were not significant from non-stored samples. TBARs content, corrected to MDA, in both cooked breast and leg muscle meats from tallow fed birds increased (P<0.05) to a higher extent over a 3 to 5-day storage period, compared to counterparts derived from the lecithin fed diets. This result indicated an antioxidant effect of feeding lecithin on both PUFA retention and reduced MDA. Descriptive sensory analysis with panelists trained to rank for lipid oxidation identified significant changes in flavor in 5-day refrigerated meats (e.g. cardboard flavor, oxidized aftertaste and sour taste) compared to lecithin fed counterparts.