Glycerin as a factor for moderating quality changes in table eggs during storage

Glycerol, a by-product of biodiesel production, is non-toxic to humans andthe environment. With the current increase in the demand for fuels obtained frombiomass, the amount of glycerine waste production is increasing. There are many ways todispose this substance (in pharmaceuticals, cosmetics, and in chemical industry),but its utilization is still insufficient. Therefore, the aim of this study was to assessthe possibility of limiting quality changes in table eggs duringstorage by coating the shells with a glycerol solution. The material used in this research consistedof 270 table chicken eggs collected on the same day. On the first day of theexperiment, quality traits of 30 eggs were evaluated (initial control group). Theremaining 240 eggs were divided into two equal groups: control (eggs thatwere not subjected to any treatment) and experimental (eggs that were coated with a5 % aqueous solution of glycerol). The eggs were placed on transporttrays and stored at 14 °C and 70 % humidity. Qualityevaluations were carried out after 14 and 28 days of storage. The depth of the air cell,mass and specific gravity of the egg, the shell characteristics (water vapourconductance, strength, mass, thickness, and density), and the content traits (pHof the albumen and yolk, Haugh units, and colour and weight of the yolk) were evaluated.The results obtained suggest that the use of glycerine may contribute toslowing adverse changes in egg quality during storage by limitingCO₂ removal from the egg content, which allows the egg to maintain albumenstructure. Due to the fact that glycerine is a safe, cheap, and easy-to-applysubstance, its large-scale use in poultry raw material storage seems to be a very real possibility.