Manipulation of the n-3 polyunsaturated fatty acid composition of avian eggs and meat

Abstract

An imbalance in the human dietary intake of various types of fatty acids has become apparent. Results of fundamental studies have shown specific and beneficial effects on human health and well-being through the consumption of the long chain n-3 polyunsaturated fatty acids, in particular eicosapentaenoic acid and docosahexaenoic acid, which play an important role in rectifying this imbalance. As a result of these observations, recent recommendations pertaining to the consumption of dietary fat have stressed the importance of consuming higher levels of these fatty acids. In addition to increasing oily fish consumption, intake of the n-3 polyunsaturates can be enhanced through the consumption of commonly occurring non-fish foods containing elevated levels of these fatty acids. The fatty acid composition of the lipids of avian egg yolk and muscle tissues may be modified to match human nutritional guidelines better by appropriately manipulating the fatty acid composition of the diet; for example, modifications of the avian diet have raised total n-3 fatty acid content in egg yolk to over 200mg. Beneficial effects on blood lipoprotein characteristics in humans who consumed eggs with such modified fatty acid contents have been recorded. As in the case of eggs, meaningful quantities of n-3 polyunsaturates have been incorporated into major poultry muscle tissues. Concerns have been expressed over the development of unacceptable odours in eggs and meat from birds fed diets with increased polyunsaturation. However, by using only high quality materials, limiting the amount of fish oil or fishmeal within the diet and optimising the provision of supplemental dietary antioxidants, the production of eggs and meat with increased n-3 polyunsaturates is practicable.