Effects of heat treatments and edible shell coatings on egg quality after storage at room temperature

Abstract

The objective of this study was to evaluate the effect of thermal treatments using different water temperatures and immersion times, as well as the application of eggshell coatings using edible materials on eggshell quality after storage for 4 weeks at room temperature (22.8 ± 4.4 °C). A total of 180 brown fresh eggs were distributed in a completely randomized design with six treatments and five replicates of six eggs each. The treatments consisted of a control group without any treatment (T1), three groups treated thermally: 56 °C/32 minutes (T2); 56 °C/20 minutes (T3); 56 °C/10 minutes (T4); and two groups with gelatin 2% (T5) and 5% NaCl solution (T6). After storage, it was found that the heat treatments at 56 °C for 10, 20 and 32 minutes provided maintenance of the albumen height, which reflected the values of the Haugh units but negatively influenced the albumen foam stability. The treatment with 5% NaCl solution showed the lowest lipid oxidation rate and the best albumen foam stability. The proposed treatments (thermal or coatings), individually, caused significant improvements on some eggs quality markers evaluated after 30 days of storage.