Effect of Vitamin E Supplementation on Egg Yolk Quality and Oxidative Stability

This study was carried out to evaluate the effect of dietary vitamin E supplementation on oxidative stability in cooked egg yolk. A total of 240 ISA hens were used and divided into two uniform groups: water with a vitamin E supplementation (450 ppm) was used in the experimental group, while for the control group only pure water (100%) was used. Eggs were collected daily after 30 days of feeding and stored at 4°C. Lastly eggs were boiled in water at 100°C for 10 minutes and egg quality was immediately tested (0 days). The advance of the oxidative state was further assessed at 6 days of storage at 4°C after cooking. The obtained results show that the colour and α-tochopherol concentration of egg yolk were significantly different between the two groups, at 0 days. The malondialdehyde (MDA) value and hexanal % were higher at the two storage time after cooking in the control group than the experimental one, probably due to antioxidant activity of vitamin E. During storage, the oxidative stability decreases in both groups.