Effect of Cold Chain on Chicken Egg Quality in a Simulated Post Washing Processing and Consumer Storage Model

ABSTRACT This study assessed the effect of the cold chain on egg quality in a model simulation of post-washing processing and consumer storage. Post-washed eggs were assigned to 12 groups that simulated the conditions of temporary storage after washing (step 1; 7°C or 25°C for 1 day), transportation (step 2; 7°C or 30°C for 8 h), and selling or storage (step 3; 7°C, 25°C or 30°C for 4 weeks). The freshness and microbial characteristics of the eggs were analyzed for 4 weeks. High-temperature conditions in steps 1 or 2 resulted in reduced quality and more bacteria on eggshells, and this egg quality deterioration worsened after storage for over 2 weeks. In step 3, the quality of the eggs stored at 7°C was maintained during the entire storage, whereas the eggs stored at 25°C had lower quality and broken vitelline membranes in week 4, and the eggs stored at 30°C were spoiled. Eggs should be stored from post-washing until storage by consumers in a cold environment without interruption of temperature control to maintain quality and safety. Consumers must be aware that eggs should be stored at refrigerator temperature.

摘要
本研究通过构建模型模拟洗后加工及消费者储存场景，评估了冷链对禽蛋品质的影响。研究将洗后鸡蛋分为12组，分别模拟洗后暂存（步骤1：7℃或25℃条件下放置1天）、运输（步骤2：7℃或30℃条件下放置8小时）以及售卖或储存（步骤3：7℃、25℃或30℃条件下放置4周）的环境条件。本研究对鸡蛋的新鲜度与微生物特性开展了为期4周的检测分析。结果表明，步骤1或步骤2中的高温条件会导致禽蛋品质下降、蛋壳表面菌落数增多，且该品质劣变在储存超过2周后进一步加剧。在步骤3中，7℃储存的鸡蛋在整个储存周期内品质均保持稳定；25℃储存的鸡蛋在第4周时出现品质下降且卵黄膜（vitelline membrane）破裂的情况；30℃储存的鸡蛋则完全变质。为维持禽蛋品质与食用安全性，从洗后到消费者储存的全流程均应在可控低温环境中进行，且温控不可中断。消费者需知晓，鸡蛋应储存于冰箱冷藏温度环境中。