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.

摘要 本研究旨在评估不同水温、浸泡时长的热处理工艺，以及采用可食用材料制备的蛋壳涂层，对室温（22.8±4.4℃）储存4周后的鸡蛋蛋壳品质的影响。试验共选用180枚新鲜褐壳鸡蛋，采用完全随机试验设计，设置6个处理组，每组含5个重复，每个重复6枚鸡蛋。处理组具体为：无任何处理的空白对照组（T1）；3组热处理组：56℃/32分钟（T2）、56℃/20分钟（T3）、56℃/10分钟（T4）；以及2组涂层处理组：2%明胶处理组（T5）与5%氯化钠溶液处理组（T6）。储存周期结束后检测结果显示，56℃下分别处理10、20、32分钟的热处理工艺可维持蛋清高度，该结果与哈氏单位（Haugh units）的检测趋势一致，但会对蛋清泡沫稳定性产生负面影响。5%氯化钠溶液处理组的脂质氧化速率最低，且蛋清泡沫稳定性最优。本研究所提出的各类处理方案（热处理或涂层处理），均可在储存30天后对部分鸡蛋品质指标产生显著改善效果。