Authors
Title
Abstract
The objective of the research study was to assess the changes in selected quality traits of hen eggs after washing their shells and with focus on the storage time. The research material consisted of eggs produced by Hy-Line Brown laying hens during the 33rd week of their life. The birds were reared in one building and had access to green runs. Based on the shell cleanness criterion, the eggs were divided into 2 groups of 540 eggs each. Group I was a control group, the eggs in Group II were washed in water of 30 °C for 3 min. All the eggs, stored under a temperature of 15-18 ºC and a humidity of 50-70 %, were weighed on the day of laying and, next, on the 7th, 14th, 21st, and 28th day. The depth of air in the storing place was determined on the day when the eggs were weighed. On the 1st and the 28th day, 120 eggs were taken to assess the quality of their content. The traits of egg shells were assessed (crushing strength, weight, thickness, density) as were the traits of albumen (weight, height, pH) and yolk (colour, weight, pH). The majority of egg traits analysed changed during storage. The washing of egg shells had no effect on the egg weight loss during storage. The washing diversified the depth of air cell, the thickness and strength of shell, and, slightly, the weight and content of yolk, as well as the number of Haugh units after 28 days. The results obtained prove that the ban on washing eggs from Class A, substantiated by the drop in their quality traits, seems to be unjustified.
Keywords
washing of egg shell, free-range rearing, storage of eggs, quality of eggs