Effect of Hens Age and Storage Time on Functional and Physiochemical Properties of Eggs

In this study, we aimed to determine the effect of hens age and storage time on the functional and physicochemical properties of eggs. Eggs from hens 25–26, 45–46, 55–56, and 69–70 wk of age were assessed, when fresh (0 d) and after storage 3, 6, and 9 d at 30°C and at 50% humidity. As hens age and storage time progressed, albumen height, Haugh unit (HU) score, yolk index (YI), and vitelline membrane strength (force breaking and elasticity) significantly decreased. The values of albumen height, HU, and YI were found to be higher in eggs obtained from the younger hens (25–26 wk of age) than those from the older hens. A significant effect of hens age was also found on the yolk pH and water activity. There was no statistical difference observed between the analyzed parameters of eggs from older hens (45–70 wk of age). There was no effect of hens age on the egg quality that was found to be the best when fresh. Interaction between hens age and the storage time also had significant impact on egg weight, albumen height, HU, yolk pH and YI, yolk weight, yolk ratio, and water activity. HU and YI scores were found to be greatly influenced by the age of hens and storage time of eggs. Changes of egg quality from the younger and older hens during storage have proceeded similarly, but eggs from older hens had significantly higher eggs weight and yolk weight that changed slowly.