Egg Yolk Antioxidants Profiles: Effect of Diet Supplementation with Linseeds and Tomato-Red Pepper Mixture before and after Storage

Abstract

This study evaluated the effect of dietary incorporation of linseed alone or along with dried tomato paste-pepper powder mix on egg physical characteristics, antioxidant profiles, lipid oxidative status, and yolk coloration before and after storage at 4 °C for one month. Sixty Novogen White laying hens, 27 weeks-old, were divided into three groups and given 100 g/hen/day of a standard diet (C), standard diet containing 4.5% of ground linseed (L), linseed diet containing 1% of dried tomato paste and 1% of sweet red pepper (LTP). Linseeds increased (p < 0.05) egg yolk antioxidant capacity but not lipid oxidative stability (p > 0.05). However, dietary inclusion of LTP did not improve fresh egg yolk antioxidant activity and lipid oxidation stability (p > 0.05). With reference to the stored eggs, only antioxidant activity measured by phosphomolybdenum reduction and lipid oxidative stability were influenced (p < 0.05) by the dietary treatment. Fresh egg yolk of hens fed on linseeds tended to have a slightly more yellow, redder, and less light color than the eggs of hens fed with the control diet. Dietary supplementation of LTP increased (p < 0.05) the Roche yolk color fan (RYCF) score and redness (a*) and decreased (p < 0.05) lightness (L*) without affecting (p > 0.05) saturation (C*). Storage of hens’ eggs fed on the control diet did not influence (p > 0.05) yolk color.