Nutritive value of poultry meat: relationship between vitamin E and PUFA

Abstract

Fat content in poultry meat is relatively low (2.8 g/100 g breast and 13 g/100g thigh) and with a positive unsaturated/saturated fatty acid ratio, from a human health point of view. It is well established that we can modify lipid fraction through dietary strategies in order to improve nutritive value. When the dietary polyunsaturated fatty acid (PUFA) level increases, the PUFA content in the chicken tissues also increases. But this enrichment in PUFA, especially in omega-3, leads to a higher number of double bonds in the meat and this provokes different consequences. The use of dietary PUFA fat causes a decrease in the body fat deposition in broilers. Furthermore, an increase in the degree of PUFA in meat enhances the development of organoleptic problems and increases the susceptibility to oxidation. Since antioxidants, especially vitamin E, protect PUFA from oxidation damage, its inclusion in chicken diets must be assured. Alpha-Tocopherol (alpha-Toc) content in poultry meat increases linearly as the dietary alpha-Toc supplementation increases, but it is affected by the PUFA content. As the dietary PUFA level increases, the alpha-Toc content of chicken meat decreases. To achieve the same tissue alpha-Toc concentration, the vitamin E requirements increase by 2.5 and 3.7 mg per each g of dietary PUFA. The potential healthy beneficial effect of PUFA enriched meat will be limited if the antioxidant content, such as vitamin E, which prevents oxidation, is not assured. The dietary supplementation with alpha-Toc and PUFA should be adjusted depending on our aims: nutrient enrichment and/or lipid oxidation minimization.